dmlc--dgl/tests/python/pytorch/nn/test_nn.py

import io
import pickle
import random
import re
from copy import deepcopy

import backend as F

import dgl
import dgl.function as fn
import dgl.nn.pytorch as nn
import networkx as nx
import numpy as np  # For setting seed for scipy
import pytest
import scipy as sp
import torch
import torch as th
from dgl import shortest_dist
from torch.nn.utils.rnn import pad_sequence
from torch.optim import Adam, SparseAdam
from torch.utils.data import DataLoader
from utils import parametrize_idtype
from utils.graph_cases import (
    get_cases,
    random_bipartite,
    random_dglgraph,
    random_graph,
)

# Set seeds to make tests fully reproducible.
SEED = 12345  # random.randint(1, 99999)
random.seed(SEED)  # For networkx
np.random.seed(SEED)  # For scipy
dgl.seed(SEED)
F.seed(SEED)

tmp_buffer = io.BytesIO()


def _AXWb(A, X, W, b):
    X = th.matmul(X, W)
    Y = th.matmul(A, X.view(X.shape[0], -1)).view_as(X)
    return Y + b


def graph_with_nodes(num_nodes, ctx=None):
    g = dgl.from_networkx(nx.path_graph(num_nodes))
    return g.to(ctx) if ctx else g


@pytest.mark.parametrize("out_dim", [1, 2])
def test_graph_conv0(out_dim):
    ctx = F.ctx()
    g = graph_with_nodes(3, ctx)
    adj = g.adj_external(transpose=True, ctx=ctx)

    conv = nn.GraphConv(5, out_dim, norm="none", bias=True)
    conv = conv.to(ctx)
    print(conv)

    # test pickle
    th.save(conv, tmp_buffer)

    # test#1: basic
    h0 = F.ones((3, 5))
    h1 = conv(g, h0)
    assert len(g.ndata) == 0
    assert len(g.edata) == 0
    assert F.allclose(h1, _AXWb(adj, h0, conv.weight, conv.bias))
    # test#2: more-dim
    h0 = F.ones((3, 5, 5))
    h1 = conv(g, h0)
    assert len(g.ndata) == 0
    assert len(g.edata) == 0
    assert F.allclose(h1, _AXWb(adj, h0, conv.weight, conv.bias))

    conv = nn.GraphConv(5, out_dim)
    conv = conv.to(ctx)
    # test#3: basic
    h0 = F.ones((3, 5))
    h1 = conv(g, h0)
    assert len(g.ndata) == 0
    assert len(g.edata) == 0
    # test#4: basic
    h0 = F.ones((3, 5, 5))
    h1 = conv(g, h0)
    assert len(g.ndata) == 0
    assert len(g.edata) == 0

    conv = nn.GraphConv(5, out_dim)
    conv = conv.to(ctx)
    # test#3: basic
    h0 = F.ones((3, 5))
    h1 = conv(g, h0)
    assert len(g.ndata) == 0
    assert len(g.edata) == 0
    # test#4: basic
    h0 = F.ones((3, 5, 5))
    h1 = conv(g, h0)
    assert len(g.ndata) == 0
    assert len(g.edata) == 0

    # test rest_parameters
    old_weight = deepcopy(conv.weight.data)
    conv.reset_parameters()
    new_weight = conv.weight.data
    assert not F.allclose(old_weight, new_weight)


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["homo", "bipartite"], exclude=["zero-degree", "dglgraph"])
)
@pytest.mark.parametrize("norm", ["none", "both", "right", "left"])
@pytest.mark.parametrize("weight", [True, False])
@pytest.mark.parametrize("bias", [True, False])
@pytest.mark.parametrize("out_dim", [1, 2])
def test_graph_conv(idtype, g, norm, weight, bias, out_dim):
    # Test one tensor input
    g = g.astype(idtype).to(F.ctx())
    conv = nn.GraphConv(5, out_dim, norm=norm, weight=weight, bias=bias).to(
        F.ctx()
    )
    ext_w = F.randn((5, out_dim)).to(F.ctx())
    nsrc = g.number_of_src_nodes()
    ndst = g.number_of_dst_nodes()
    h = F.randn((nsrc, 5)).to(F.ctx())
    if weight:
        h_out = conv(g, h)
    else:
        h_out = conv(g, h, weight=ext_w)
    assert h_out.shape == (ndst, out_dim)


@parametrize_idtype
@pytest.mark.parametrize(
    "g",
    get_cases(["has_scalar_e_feature"], exclude=["zero-degree", "dglgraph"]),
)
@pytest.mark.parametrize("norm", ["none", "both", "right"])
@pytest.mark.parametrize("weight", [True, False])
@pytest.mark.parametrize("bias", [True, False])
@pytest.mark.parametrize("out_dim", [1, 2])
def test_graph_conv_e_weight(idtype, g, norm, weight, bias, out_dim):
    g = g.astype(idtype).to(F.ctx())
    conv = nn.GraphConv(5, out_dim, norm=norm, weight=weight, bias=bias).to(
        F.ctx()
    )
    ext_w = F.randn((5, out_dim)).to(F.ctx())
    nsrc = g.number_of_src_nodes()
    ndst = g.number_of_dst_nodes()
    h = F.randn((nsrc, 5)).to(F.ctx())
    e_w = g.edata["scalar_w"]
    if weight:
        h_out = conv(g, h, edge_weight=e_w)
    else:
        h_out = conv(g, h, weight=ext_w, edge_weight=e_w)
    assert h_out.shape == (ndst, out_dim)


@parametrize_idtype
@pytest.mark.parametrize(
    "g",
    get_cases(["has_scalar_e_feature"], exclude=["zero-degree", "dglgraph"]),
)
@pytest.mark.parametrize("norm", ["none", "both", "right"])
@pytest.mark.parametrize("weight", [True, False])
@pytest.mark.parametrize("bias", [True, False])
@pytest.mark.parametrize("out_dim", [1, 2])
def test_graph_conv_e_weight_norm(idtype, g, norm, weight, bias, out_dim):
    g = g.astype(idtype).to(F.ctx())
    conv = nn.GraphConv(5, out_dim, norm=norm, weight=weight, bias=bias).to(
        F.ctx()
    )

    # test pickle
    th.save(conv, tmp_buffer)

    ext_w = F.randn((5, out_dim)).to(F.ctx())
    nsrc = g.number_of_src_nodes()
    ndst = g.number_of_dst_nodes()
    h = F.randn((nsrc, 5)).to(F.ctx())
    edgenorm = nn.EdgeWeightNorm(norm=norm)
    norm_weight = edgenorm(g, g.edata["scalar_w"])
    if weight:
        h_out = conv(g, h, edge_weight=norm_weight)
    else:
        h_out = conv(g, h, weight=ext_w, edge_weight=norm_weight)
    assert h_out.shape == (ndst, out_dim)


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["bipartite"], exclude=["zero-degree", "dglgraph"])
)
@pytest.mark.parametrize("norm", ["none", "both", "right"])
@pytest.mark.parametrize("weight", [True, False])
@pytest.mark.parametrize("bias", [True, False])
@pytest.mark.parametrize("out_dim", [1, 2])
def test_graph_conv_bi(idtype, g, norm, weight, bias, out_dim):
    # Test a pair of tensor inputs
    g = g.astype(idtype).to(F.ctx())
    conv = nn.GraphConv(5, out_dim, norm=norm, weight=weight, bias=bias).to(
        F.ctx()
    )

    # test pickle
    th.save(conv, tmp_buffer)

    ext_w = F.randn((5, out_dim)).to(F.ctx())
    nsrc = g.number_of_src_nodes()
    ndst = g.number_of_dst_nodes()
    h = F.randn((nsrc, 5)).to(F.ctx())
    h_dst = F.randn((ndst, out_dim)).to(F.ctx())
    if weight:
        h_out = conv(g, (h, h_dst))
    else:
        h_out = conv(g, (h, h_dst), weight=ext_w)
    assert h_out.shape == (ndst, out_dim)


def _S2AXWb(A, N, X, W, b):
    X1 = X * N
    X1 = th.matmul(A, X1.view(X1.shape[0], -1))
    X1 = X1 * N
    X2 = X1 * N
    X2 = th.matmul(A, X2.view(X2.shape[0], -1))
    X2 = X2 * N
    X = th.cat([X, X1, X2], dim=-1)
    Y = th.matmul(X, W.rot90())

    return Y + b


@pytest.mark.parametrize("out_dim", [1, 2])
def test_tagconv(out_dim):
    ctx = F.ctx()
    g = graph_with_nodes(3, ctx)
    adj = g.adj_external(transpose=True, ctx=ctx)
    norm = th.pow(g.in_degrees().float(), -0.5)

    conv = nn.TAGConv(5, out_dim, bias=True)
    conv = conv.to(ctx)
    print(conv)

    # test pickle
    th.save(conv, tmp_buffer)

    # test#1: basic
    h0 = F.ones((3, 5))
    h1 = conv(g, h0)
    assert len(g.ndata) == 0
    assert len(g.edata) == 0
    shp = norm.shape + (1,) * (h0.dim() - 1)
    norm = th.reshape(norm, shp).to(ctx)

    assert F.allclose(
        h1, _S2AXWb(adj, norm, h0, conv.lin.weight, conv.lin.bias)
    )

    conv = nn.TAGConv(5, out_dim)
    conv = conv.to(ctx)

    # test#2: basic
    h0 = F.ones((3, 5))
    h1 = conv(g, h0)
    assert h1.shape[-1] == out_dim

    # test reset_parameters
    old_weight = deepcopy(conv.lin.weight.data)
    conv.reset_parameters()
    new_weight = conv.lin.weight.data
    assert not F.allclose(old_weight, new_weight)


def test_set2set():
    ctx = F.ctx()
    g = graph_with_nodes(10, ctx)

    s2s = nn.Set2Set(5, 3, 3)  # hidden size 5, 3 iters, 3 layers
    s2s = s2s.to(ctx)
    print(s2s)

    # test#1: basic
    h0 = F.randn((g.num_nodes(), 5))
    h1 = s2s(g, h0)
    assert h1.shape[0] == 1 and h1.shape[1] == 10 and h1.dim() == 2

    # test#2: batched graph
    g1 = graph_with_nodes(11, ctx)
    g2 = graph_with_nodes(5, ctx)
    bg = dgl.batch([g, g1, g2])
    h0 = F.randn((bg.num_nodes(), 5))
    h1 = s2s(bg, h0)
    assert h1.shape[0] == 3 and h1.shape[1] == 10 and h1.dim() == 2


def test_glob_att_pool():
    ctx = F.ctx()
    g = graph_with_nodes(10, ctx)

    gap = nn.GlobalAttentionPooling(th.nn.Linear(5, 1), th.nn.Linear(5, 10))
    gap = gap.to(ctx)
    print(gap)

    # test pickle
    th.save(gap, tmp_buffer)

    # test#1: basic
    h0 = F.randn((g.num_nodes(), 5))
    h1 = gap(g, h0)
    assert h1.shape[0] == 1 and h1.shape[1] == 10 and h1.dim() == 2

    # test#2: batched graph
    bg = dgl.batch([g, g, g, g])
    h0 = F.randn((bg.num_nodes(), 5))
    h1 = gap(bg, h0)
    assert h1.shape[0] == 4 and h1.shape[1] == 10 and h1.dim() == 2


def test_simple_pool():
    ctx = F.ctx()
    g = graph_with_nodes(15, ctx)

    sum_pool = nn.SumPooling()
    avg_pool = nn.AvgPooling()
    max_pool = nn.MaxPooling()
    sort_pool = nn.SortPooling(10)  # k = 10
    print(sum_pool, avg_pool, max_pool, sort_pool)

    # test#1: basic
    h0 = F.randn((g.num_nodes(), 5))
    sum_pool = sum_pool.to(ctx)
    avg_pool = avg_pool.to(ctx)
    max_pool = max_pool.to(ctx)
    sort_pool = sort_pool.to(ctx)
    h1 = sum_pool(g, h0)
    assert F.allclose(F.squeeze(h1, 0), F.sum(h0, 0))
    h1 = avg_pool(g, h0)
    assert F.allclose(F.squeeze(h1, 0), F.mean(h0, 0))
    h1 = max_pool(g, h0)
    assert F.allclose(F.squeeze(h1, 0), F.max(h0, 0))
    h1 = sort_pool(g, h0)
    assert h1.shape[0] == 1 and h1.shape[1] == 10 * 5 and h1.dim() == 2

    # test#2: batched graph
    g_ = graph_with_nodes(5, ctx)
    bg = dgl.batch([g, g_, g, g_, g])
    h0 = F.randn((bg.num_nodes(), 5))
    h1 = sum_pool(bg, h0)
    truth = th.stack(
        [
            F.sum(h0[:15], 0),
            F.sum(h0[15:20], 0),
            F.sum(h0[20:35], 0),
            F.sum(h0[35:40], 0),
            F.sum(h0[40:55], 0),
        ],
        0,
    )
    assert F.allclose(h1, truth)

    h1 = avg_pool(bg, h0)
    truth = th.stack(
        [
            F.mean(h0[:15], 0),
            F.mean(h0[15:20], 0),
            F.mean(h0[20:35], 0),
            F.mean(h0[35:40], 0),
            F.mean(h0[40:55], 0),
        ],
        0,
    )
    assert F.allclose(h1, truth)

    h1 = max_pool(bg, h0)
    truth = th.stack(
        [
            F.max(h0[:15], 0),
            F.max(h0[15:20], 0),
            F.max(h0[20:35], 0),
            F.max(h0[35:40], 0),
            F.max(h0[40:55], 0),
        ],
        0,
    )
    assert F.allclose(h1, truth)

    h1 = sort_pool(bg, h0)
    assert h1.shape[0] == 5 and h1.shape[1] == 10 * 5 and h1.dim() == 2


def test_set_trans():
    ctx = F.ctx()
    g = graph_with_nodes(15)

    st_enc_0 = nn.SetTransformerEncoder(50, 5, 10, 100, 2, "sab")
    st_enc_1 = nn.SetTransformerEncoder(50, 5, 10, 100, 2, "isab", 3)
    st_dec = nn.SetTransformerDecoder(50, 5, 10, 100, 2, 4)
    st_enc_0 = st_enc_0.to(ctx)
    st_enc_1 = st_enc_1.to(ctx)
    st_dec = st_dec.to(ctx)
    print(st_enc_0, st_enc_1, st_dec)

    # test#1: basic
    h0 = F.randn((g.num_nodes(), 50))
    h1 = st_enc_0(g, h0)
    assert h1.shape == h0.shape
    h1 = st_enc_1(g, h0)
    assert h1.shape == h0.shape
    h2 = st_dec(g, h1)
    assert h2.shape[0] == 1 and h2.shape[1] == 200 and h2.dim() == 2

    # test#2: batched graph
    g1 = graph_with_nodes(5)
    g2 = graph_with_nodes(10)
    bg = dgl.batch([g, g1, g2])
    h0 = F.randn((bg.num_nodes(), 50))
    h1 = st_enc_0(bg, h0)
    assert h1.shape == h0.shape
    h1 = st_enc_1(bg, h0)
    assert h1.shape == h0.shape

    h2 = st_dec(bg, h1)
    assert h2.shape[0] == 3 and h2.shape[1] == 200 and h2.dim() == 2


@parametrize_idtype
@pytest.mark.parametrize("O", [1, 8, 32])
def test_rgcn(idtype, O):
    ctx = F.ctx()
    etype = []
    g = dgl.from_scipy(sp.sparse.random(100, 100, density=0.1))
    g = g.astype(idtype).to(F.ctx())
    # 5 etypes
    R = 5
    for i in range(g.num_edges()):
        etype.append(i % 5)
    B = 2
    I = 10

    h = th.randn((100, I)).to(ctx)
    r = th.tensor(etype).to(ctx)
    norm = th.rand((g.num_edges(), 1)).to(ctx)
    sorted_r, idx = th.sort(r)
    sorted_g = dgl.reorder_graph(
        g,
        edge_permute_algo="custom",
        permute_config={"edges_perm": idx.to(idtype)},
    )
    sorted_norm = norm[idx]

    rgc = nn.RelGraphConv(I, O, R).to(ctx)
    th.save(rgc, tmp_buffer)  # test pickle
    rgc_basis = nn.RelGraphConv(I, O, R, "basis", B).to(ctx)
    th.save(rgc_basis, tmp_buffer)  # test pickle
    if O % B == 0:
        rgc_bdd = nn.RelGraphConv(I, O, R, "bdd", B).to(ctx)
        th.save(rgc_bdd, tmp_buffer)  # test pickle

    # basic usage
    h_new = rgc(g, h, r)
    assert h_new.shape == (100, O)
    h_new_basis = rgc_basis(g, h, r)
    assert h_new_basis.shape == (100, O)
    if O % B == 0:
        h_new_bdd = rgc_bdd(g, h, r)
        assert h_new_bdd.shape == (100, O)

    # sorted input
    h_new_sorted = rgc(sorted_g, h, sorted_r, presorted=True)
    assert th.allclose(h_new, h_new_sorted, atol=1e-4, rtol=1e-4)
    h_new_basis_sorted = rgc_basis(sorted_g, h, sorted_r, presorted=True)
    assert th.allclose(h_new_basis, h_new_basis_sorted, atol=1e-4, rtol=1e-4)
    if O % B == 0:
        h_new_bdd_sorted = rgc_bdd(sorted_g, h, sorted_r, presorted=True)
        assert th.allclose(h_new_bdd, h_new_bdd_sorted, atol=1e-4, rtol=1e-4)

    # norm input
    h_new = rgc(g, h, r, norm)
    assert h_new.shape == (100, O)
    h_new = rgc_basis(g, h, r, norm)
    assert h_new.shape == (100, O)
    if O % B == 0:
        h_new = rgc_bdd(g, h, r, norm)
        assert h_new.shape == (100, O)


@parametrize_idtype
@pytest.mark.parametrize("O", [1, 10, 40])
def test_rgcn_default_nbasis(idtype, O):
    ctx = F.ctx()
    etype = []
    g = dgl.from_scipy(sp.sparse.random(100, 100, density=0.1))
    g = g.astype(idtype).to(F.ctx())
    # 5 etypes
    R = 5
    for i in range(g.num_edges()):
        etype.append(i % 5)
    I = 10

    h = th.randn((100, I)).to(ctx)
    r = th.tensor(etype).to(ctx)
    norm = th.rand((g.num_edges(), 1)).to(ctx)
    sorted_r, idx = th.sort(r)
    sorted_g = dgl.reorder_graph(
        g,
        edge_permute_algo="custom",
        permute_config={"edges_perm": idx.to(idtype)},
    )
    sorted_norm = norm[idx]

    rgc = nn.RelGraphConv(I, O, R).to(ctx)
    th.save(rgc, tmp_buffer)  # test pickle
    rgc_basis = nn.RelGraphConv(I, O, R, "basis").to(ctx)
    th.save(rgc_basis, tmp_buffer)  # test pickle
    if O % R == 0:
        rgc_bdd = nn.RelGraphConv(I, O, R, "bdd").to(ctx)
        th.save(rgc_bdd, tmp_buffer)  # test pickle

    # basic usage
    h_new = rgc(g, h, r)
    assert h_new.shape == (100, O)
    h_new_basis = rgc_basis(g, h, r)
    assert h_new_basis.shape == (100, O)
    if O % R == 0:
        h_new_bdd = rgc_bdd(g, h, r)
        assert h_new_bdd.shape == (100, O)

    # sorted input
    h_new_sorted = rgc(sorted_g, h, sorted_r, presorted=True)
    assert th.allclose(h_new, h_new_sorted, atol=1e-4, rtol=1e-4)
    h_new_basis_sorted = rgc_basis(sorted_g, h, sorted_r, presorted=True)
    assert th.allclose(h_new_basis, h_new_basis_sorted, atol=1e-4, rtol=1e-4)
    if O % R == 0:
        h_new_bdd_sorted = rgc_bdd(sorted_g, h, sorted_r, presorted=True)
        assert th.allclose(h_new_bdd, h_new_bdd_sorted, atol=1e-4, rtol=1e-4)

    # norm input
    h_new = rgc(g, h, r, norm)
    assert h_new.shape == (100, O)
    h_new = rgc_basis(g, h, r, norm)
    assert h_new.shape == (100, O)
    if O % R == 0:
        h_new = rgc_bdd(g, h, r, norm)
        assert h_new.shape == (100, O)


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["homo", "block-bipartite"], exclude=["zero-degree"])
)
@pytest.mark.parametrize("out_dim", [1, 5])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_gat_conv(g, idtype, out_dim, num_heads):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    gat = nn.GATConv(5, out_dim, num_heads)
    feat = F.randn((g.number_of_src_nodes(), 5))
    gat = gat.to(ctx)
    h = gat(g, feat)

    # test pickle
    th.save(gat, tmp_buffer)

    assert h.shape == (g.number_of_dst_nodes(), num_heads, out_dim)
    _, a = gat(g, feat, get_attention=True)
    assert a.shape == (g.num_edges(), num_heads, 1)

    # test residual connection
    gat = nn.GATConv(5, out_dim, num_heads, residual=True)
    gat = gat.to(ctx)
    h = gat(g, feat)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_dim", [1, 2])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_gat_conv_bi(g, idtype, out_dim, num_heads):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    gat = nn.GATConv(5, out_dim, num_heads)
    feat = (
        F.randn((g.number_of_src_nodes(), 5)),
        F.randn((g.number_of_dst_nodes(), 5)),
    )
    gat = gat.to(ctx)
    h = gat(g, feat)
    assert h.shape == (g.number_of_dst_nodes(), num_heads, out_dim)
    _, a = gat(g, feat, get_attention=True)
    assert a.shape == (g.num_edges(), num_heads, 1)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_dim", [1, 2])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_gat_conv_edge_weight(g, idtype, out_dim, num_heads):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    gat = nn.GATConv(5, out_dim, num_heads)
    feat = (
        F.randn((g.number_of_src_nodes(), 5)),
        F.randn((g.number_of_dst_nodes(), 5)),
    )
    gat = gat.to(ctx)
    ew = F.randn((g.num_edges(),))
    h = gat(g, feat, edge_weight=ew)
    assert h.shape == (g.number_of_dst_nodes(), num_heads, out_dim)
    _, a = gat(g, feat, get_attention=True)
    assert a.shape[0] == ew.shape[0]
    assert a.shape == (g.num_edges(), num_heads, 1)


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["homo", "block-bipartite"], exclude=["zero-degree"])
)
@pytest.mark.parametrize("out_dim", [1, 5])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_gatv2_conv(g, idtype, out_dim, num_heads):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    gat = nn.GATv2Conv(5, out_dim, num_heads)
    feat = F.randn((g.number_of_src_nodes(), 5))
    gat = gat.to(ctx)
    h = gat(g, feat)

    # test pickle
    th.save(gat, tmp_buffer)

    assert h.shape == (g.number_of_dst_nodes(), num_heads, out_dim)
    _, a = gat(g, feat, get_attention=True)
    assert a.shape == (g.num_edges(), num_heads, 1)

    # test residual connection
    gat = nn.GATConv(5, out_dim, num_heads, residual=True)
    gat = gat.to(ctx)
    h = gat(g, feat)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_dim", [1, 2])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_gatv2_conv_bi(g, idtype, out_dim, num_heads):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    gat = nn.GATv2Conv(5, out_dim, num_heads)
    feat = (
        F.randn((g.number_of_src_nodes(), 5)),
        F.randn((g.number_of_dst_nodes(), 5)),
    )
    gat = gat.to(ctx)
    h = gat(g, feat)
    assert h.shape == (g.number_of_dst_nodes(), num_heads, out_dim)
    _, a = gat(g, feat, get_attention=True)
    assert a.shape == (g.num_edges(), num_heads, 1)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_node_feats", [1, 5])
@pytest.mark.parametrize("out_edge_feats", [1, 5])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_egat_conv(g, idtype, out_node_feats, out_edge_feats, num_heads):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    egat = nn.EGATConv(
        in_node_feats=10,
        in_edge_feats=5,
        out_node_feats=out_node_feats,
        out_edge_feats=out_edge_feats,
        num_heads=num_heads,
    )
    nfeat = F.randn((g.num_nodes(), 10))
    efeat = F.randn((g.num_edges(), 5))
    egat = egat.to(ctx)
    h, f = egat(g, nfeat, efeat)

    th.save(egat, tmp_buffer)

    assert h.shape == (g.num_nodes(), num_heads, out_node_feats)
    assert f.shape == (g.num_edges(), num_heads, out_edge_feats)
    _, _, attn = egat(g, nfeat, efeat, get_attention=True)
    assert attn.shape == (g.num_edges(), num_heads, 1)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_node_feats", [1, 5])
@pytest.mark.parametrize("out_edge_feats", [1, 5])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_egat_conv_bi(g, idtype, out_node_feats, out_edge_feats, num_heads):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    egat = nn.EGATConv(
        in_node_feats=(10, 15),
        in_edge_feats=7,
        out_node_feats=out_node_feats,
        out_edge_feats=out_edge_feats,
        num_heads=num_heads,
    )
    nfeat = (
        F.randn((g.number_of_src_nodes(), 10)),
        F.randn((g.number_of_dst_nodes(), 15)),
    )
    efeat = F.randn((g.num_edges(), 7))
    egat = egat.to(ctx)
    h, f = egat(g, nfeat, efeat)

    th.save(egat, tmp_buffer)

    assert h.shape == (g.number_of_dst_nodes(), num_heads, out_node_feats)
    assert f.shape == (g.num_edges(), num_heads, out_edge_feats)
    _, _, attn = egat(g, nfeat, efeat, get_attention=True)
    assert attn.shape == (g.num_edges(), num_heads, 1)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_node_feats", [1, 5])
@pytest.mark.parametrize("out_edge_feats", [1, 5])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_egat_conv_edge_weight(
    g, idtype, out_node_feats, out_edge_feats, num_heads
):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    egat = nn.EGATConv(
        in_node_feats=10,
        in_edge_feats=5,
        out_node_feats=out_node_feats,
        out_edge_feats=out_edge_feats,
        num_heads=num_heads,
    )
    egat = egat.to(ctx)
    nfeat = F.randn((g.num_nodes(), 10))
    efeat = F.randn((g.num_edges(), 5))
    ew = F.randn((g.num_edges(),))

    h, f, attn = egat(g, nfeat, efeat, edge_weight=ew, get_attention=True)

    assert h.shape == (g.num_nodes(), num_heads, out_node_feats)
    assert f.shape == (g.num_edges(), num_heads, out_edge_feats)
    assert attn.shape == (g.num_edges(), num_heads, 1)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_feats", [1, 5])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_edgegat_conv(g, idtype, out_feats, num_heads):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    edgegat = nn.EdgeGATConv(
        in_feats=10, edge_feats=5, out_feats=out_feats, num_heads=num_heads
    )
    nfeat = F.randn((g.number_of_nodes(), 10))
    efeat = F.randn((g.number_of_edges(), 5))
    edgegat = edgegat.to(ctx)
    h = edgegat(g, nfeat, efeat)

    th.save(edgegat, tmp_buffer)

    assert h.shape == (g.number_of_nodes(), num_heads, out_feats)
    _, attn = edgegat(g, nfeat, efeat, True)
    assert attn.shape == (g.number_of_edges(), num_heads, 1)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_feats", [1, 5])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_edgegat_conv_bi(g, idtype, out_feats, num_heads):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    edgegat = nn.EdgeGATConv(
        in_feats=(10, 15),
        edge_feats=7,
        out_feats=out_feats,
        num_heads=num_heads,
    )
    nfeat = (
        F.randn((g.number_of_src_nodes(), 10)),
        F.randn((g.number_of_dst_nodes(), 15)),
    )
    efeat = F.randn((g.number_of_edges(), 7))
    edgegat = edgegat.to(ctx)
    h = edgegat(g, nfeat, efeat)

    th.save(edgegat, tmp_buffer)

    assert h.shape == (g.number_of_dst_nodes(), num_heads, out_feats)
    _, attn = edgegat(g, nfeat, efeat, True)
    assert attn.shape == (g.number_of_edges(), num_heads, 1)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo", "block-bipartite"]))
@pytest.mark.parametrize("aggre_type", ["mean", "pool", "gcn", "lstm"])
def test_sage_conv(idtype, g, aggre_type):
    g = g.astype(idtype).to(F.ctx())
    sage = nn.SAGEConv(5, 10, aggre_type)
    feat = F.randn((g.number_of_src_nodes(), 5))
    sage = sage.to(F.ctx())
    # test pickle
    th.save(sage, tmp_buffer)
    h = sage(g, feat)
    assert h.shape[-1] == 10


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"]))
@pytest.mark.parametrize("aggre_type", ["mean", "pool", "gcn", "lstm"])
@pytest.mark.parametrize("out_dim", [1, 2])
def test_sage_conv_bi(idtype, g, aggre_type, out_dim):
    g = g.astype(idtype).to(F.ctx())
    dst_dim = 5 if aggre_type != "gcn" else 10
    sage = nn.SAGEConv((10, dst_dim), out_dim, aggre_type)
    feat = (
        F.randn((g.number_of_src_nodes(), 10)),
        F.randn((g.number_of_dst_nodes(), dst_dim)),
    )
    sage = sage.to(F.ctx())
    h = sage(g, feat)
    assert h.shape[-1] == out_dim
    assert h.shape[0] == g.number_of_dst_nodes()


@parametrize_idtype
@pytest.mark.parametrize("out_dim", [1, 2])
def test_sage_conv2(idtype, out_dim):
    # TODO: add test for blocks
    # Test the case for graphs without edges
    g = dgl.heterograph({("_U", "_E", "_V"): ([], [])}, {"_U": 5, "_V": 3})
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    sage = nn.SAGEConv((3, 3), out_dim, "gcn")
    feat = (F.randn((5, 3)), F.randn((3, 3)))
    sage = sage.to(ctx)
    h = sage(g, (F.copy_to(feat[0], F.ctx()), F.copy_to(feat[1], F.ctx())))
    assert h.shape[-1] == out_dim
    assert h.shape[0] == 3
    for aggre_type in ["mean", "pool", "lstm"]:
        sage = nn.SAGEConv((3, 1), out_dim, aggre_type)
        feat = (F.randn((5, 3)), F.randn((3, 1)))
        sage = sage.to(ctx)
        h = sage(g, feat)
        assert h.shape[-1] == out_dim
        assert h.shape[0] == 3


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_dim", [1, 2])
def test_sgc_conv(g, idtype, out_dim):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    # not cached
    sgc = nn.SGConv(5, out_dim, 3)

    # test pickle
    th.save(sgc, tmp_buffer)

    feat = F.randn((g.num_nodes(), 5))
    sgc = sgc.to(ctx)

    h = sgc(g, feat)
    assert h.shape[-1] == out_dim

    # cached
    sgc = nn.SGConv(5, out_dim, 3, True)
    sgc = sgc.to(ctx)
    h_0 = sgc(g, feat)
    h_1 = sgc(g, feat + 1)
    assert F.allclose(h_0, h_1)
    assert h_0.shape[-1] == out_dim


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
def test_appnp_conv(g, idtype):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    appnp = nn.APPNPConv(10, 0.1)
    feat = F.randn((g.num_nodes(), 5))
    appnp = appnp.to(ctx)

    # test pickle
    th.save(appnp, tmp_buffer)

    h = appnp(g, feat)
    assert h.shape[-1] == 5


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
def test_appnp_conv_e_weight(g, idtype):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    appnp = nn.APPNPConv(10, 0.1)
    feat = F.randn((g.num_nodes(), 5))
    eweight = F.ones((g.num_edges(),))
    appnp = appnp.to(ctx)

    h = appnp(g, feat, edge_weight=eweight)
    assert h.shape[-1] == 5


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
@pytest.mark.parametrize("bias", [True, False])
def test_gcn2conv_e_weight(g, idtype, bias):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    gcn2conv = nn.GCN2Conv(
        5, layer=2, alpha=0.5, bias=bias, project_initial_features=True
    )
    feat = F.randn((g.num_nodes(), 5))
    eweight = F.ones((g.num_edges(),))
    gcn2conv = gcn2conv.to(ctx)
    res = feat
    h = gcn2conv(g, res, feat, edge_weight=eweight)
    assert h.shape[-1] == 5
    assert re.match(
        re.compile(".*GCN2Conv.*in=.*, alpha=.*, beta=.*"), str(gcn2conv)
    )


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
def test_sgconv_e_weight(g, idtype):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    sgconv = nn.SGConv(5, 5, 3)
    feat = F.randn((g.num_nodes(), 5))
    eweight = F.ones((g.num_edges(),))
    sgconv = sgconv.to(ctx)
    h = sgconv(g, feat, edge_weight=eweight)
    assert h.shape[-1] == 5


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
def test_tagconv_e_weight(g, idtype):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    conv = nn.TAGConv(5, 5, bias=True)
    conv = conv.to(ctx)
    feat = F.randn((g.num_nodes(), 5))
    eweight = F.ones((g.num_edges(),))
    conv = conv.to(ctx)
    h = conv(g, feat, edge_weight=eweight)
    assert h.shape[-1] == 5


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["homo", "block-bipartite"], exclude=["zero-degree"])
)
@pytest.mark.parametrize("aggregator_type", ["mean", "max", "sum"])
def test_gin_conv(g, idtype, aggregator_type):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    gin = nn.GINConv(th.nn.Linear(5, 12), aggregator_type)
    th.save(gin, tmp_buffer)
    feat = F.randn((g.number_of_src_nodes(), 5))
    gin = gin.to(ctx)
    h = gin(g, feat)

    # test pickle
    th.save(gin, tmp_buffer)

    assert h.shape == (g.number_of_dst_nodes(), 12)

    gin = nn.GINConv(None, aggregator_type)
    th.save(gin, tmp_buffer)
    gin = gin.to(ctx)
    h = gin(g, feat)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo", "block-bipartite"]))
def test_gine_conv(g, idtype):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    gine = nn.GINEConv(th.nn.Linear(5, 12))
    th.save(gine, tmp_buffer)
    nfeat = F.randn((g.number_of_src_nodes(), 5))
    efeat = F.randn((g.num_edges(), 5))
    gine = gine.to(ctx)
    h = gine(g, nfeat, efeat)

    # test pickle
    th.save(gine, tmp_buffer)
    assert h.shape == (g.number_of_dst_nodes(), 12)

    gine = nn.GINEConv(None)
    th.save(gine, tmp_buffer)
    gine = gine.to(ctx)
    h = gine(g, nfeat, efeat)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
@pytest.mark.parametrize("aggregator_type", ["mean", "max", "sum"])
def test_gin_conv_bi(g, idtype, aggregator_type):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    gin = nn.GINConv(th.nn.Linear(5, 12), aggregator_type)
    feat = (
        F.randn((g.number_of_src_nodes(), 5)),
        F.randn((g.number_of_dst_nodes(), 5)),
    )
    gin = gin.to(ctx)
    h = gin(g, feat)
    assert h.shape == (g.number_of_dst_nodes(), 12)


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["homo", "block-bipartite"], exclude=["zero-degree"])
)
def test_agnn_conv(g, idtype):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    agnn = nn.AGNNConv(1)
    feat = F.randn((g.number_of_src_nodes(), 5))
    agnn = agnn.to(ctx)
    h = agnn(g, feat)
    assert h.shape == (g.number_of_dst_nodes(), 5)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
def test_agnn_conv_bi(g, idtype):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    agnn = nn.AGNNConv(1)
    feat = (
        F.randn((g.number_of_src_nodes(), 5)),
        F.randn((g.number_of_dst_nodes(), 5)),
    )
    agnn = agnn.to(ctx)
    h = agnn(g, feat)
    assert h.shape == (g.number_of_dst_nodes(), 5)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
def test_gated_graph_conv(g, idtype):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    ggconv = nn.GatedGraphConv(5, 10, 5, 3)
    etypes = th.arange(g.num_edges()) % 3
    feat = F.randn((g.num_nodes(), 5))
    ggconv = ggconv.to(ctx)
    etypes = etypes.to(ctx)

    h = ggconv(g, feat, etypes)
    # current we only do shape check
    assert h.shape[-1] == 10


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
def test_gated_graph_conv_one_etype(g, idtype):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    ggconv = nn.GatedGraphConv(5, 10, 5, 1)
    etypes = th.zeros(g.num_edges())
    feat = F.randn((g.num_nodes(), 5))
    ggconv = ggconv.to(ctx)
    etypes = etypes.to(ctx)

    h = ggconv(g, feat, etypes)
    h2 = ggconv(g, feat)
    # current we only do shape check
    assert F.allclose(h, h2)
    assert h.shape[-1] == 10


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["homo", "block-bipartite"], exclude=["zero-degree"])
)
def test_nn_conv(g, idtype):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    edge_func = th.nn.Linear(4, 5 * 10)
    nnconv = nn.NNConv(5, 10, edge_func, "mean")
    feat = F.randn((g.number_of_src_nodes(), 5))
    efeat = F.randn((g.num_edges(), 4))
    nnconv = nnconv.to(ctx)
    h = nnconv(g, feat, efeat)
    # currently we only do shape check
    assert h.shape[-1] == 10


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
def test_nn_conv_bi(g, idtype):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    edge_func = th.nn.Linear(4, 5 * 10)
    nnconv = nn.NNConv((5, 2), 10, edge_func, "mean")
    feat = F.randn((g.number_of_src_nodes(), 5))
    feat_dst = F.randn((g.number_of_dst_nodes(), 2))
    efeat = F.randn((g.num_edges(), 4))
    nnconv = nnconv.to(ctx)
    h = nnconv(g, (feat, feat_dst), efeat)
    # currently we only do shape check
    assert h.shape[-1] == 10


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
def test_gmm_conv(g, idtype):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    gmmconv = nn.GMMConv(5, 10, 3, 4, "mean")
    feat = F.randn((g.num_nodes(), 5))
    pseudo = F.randn((g.num_edges(), 3))
    gmmconv = gmmconv.to(ctx)
    h = gmmconv(g, feat, pseudo)
    # currently we only do shape check
    assert h.shape[-1] == 10


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["bipartite", "block-bipartite"], exclude=["zero-degree"])
)
def test_gmm_conv_bi(g, idtype):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    gmmconv = nn.GMMConv((5, 2), 10, 3, 4, "mean")
    feat = F.randn((g.number_of_src_nodes(), 5))
    feat_dst = F.randn((g.number_of_dst_nodes(), 2))
    pseudo = F.randn((g.num_edges(), 3))
    gmmconv = gmmconv.to(ctx)
    h = gmmconv(g, (feat, feat_dst), pseudo)
    # currently we only do shape check
    assert h.shape[-1] == 10


@parametrize_idtype
@pytest.mark.parametrize("norm_type", ["both", "right", "none"])
@pytest.mark.parametrize(
    "g", get_cases(["homo", "bipartite"], exclude=["zero-degree"])
)
@pytest.mark.parametrize("out_dim", [1, 2])
def test_dense_graph_conv(norm_type, g, idtype, out_dim):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    # TODO(minjie): enable the following option after #1385
    adj = g.adj_external(transpose=True, ctx=ctx).to_dense()
    conv = nn.GraphConv(5, out_dim, norm=norm_type, bias=True)
    dense_conv = nn.DenseGraphConv(5, out_dim, norm=norm_type, bias=True)
    dense_conv.weight.data = conv.weight.data
    dense_conv.bias.data = conv.bias.data
    feat = F.randn((g.number_of_src_nodes(), 5))
    conv = conv.to(ctx)
    dense_conv = dense_conv.to(ctx)
    out_conv = conv(g, feat)
    out_dense_conv = dense_conv(adj, feat)
    assert F.allclose(out_conv, out_dense_conv)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo", "bipartite"]))
@pytest.mark.parametrize("out_dim", [1, 2])
def test_dense_sage_conv(g, idtype, out_dim):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    adj = g.adj_external(transpose=True, ctx=ctx).to_dense()
    sage = nn.SAGEConv(5, out_dim, "gcn")
    dense_sage = nn.DenseSAGEConv(5, out_dim)
    dense_sage.fc.weight.data = sage.fc_neigh.weight.data
    dense_sage.fc.bias.data = sage.bias.data
    if len(g.ntypes) == 2:
        feat = (
            F.randn((g.number_of_src_nodes(), 5)),
            F.randn((g.number_of_dst_nodes(), 5)),
        )
    else:
        feat = F.randn((g.num_nodes(), 5))
    sage = sage.to(ctx)
    dense_sage = dense_sage.to(ctx)
    out_sage = sage(g, feat)
    out_dense_sage = dense_sage(adj, feat)
    assert F.allclose(out_sage, out_dense_sage), g


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["homo", "block-bipartite"], exclude=["zero-degree"])
)
@pytest.mark.parametrize("out_dim", [1, 2])
def test_edge_conv(g, idtype, out_dim):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    edge_conv = nn.EdgeConv(5, out_dim).to(ctx)
    print(edge_conv)

    # test pickle
    th.save(edge_conv, tmp_buffer)

    h0 = F.randn((g.number_of_src_nodes(), 5))
    h1 = edge_conv(g, h0)
    assert h1.shape == (g.number_of_dst_nodes(), out_dim)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_dim", [1, 2])
def test_edge_conv_bi(g, idtype, out_dim):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    edge_conv = nn.EdgeConv(5, out_dim).to(ctx)
    print(edge_conv)
    h0 = F.randn((g.number_of_src_nodes(), 5))
    x0 = F.randn((g.number_of_dst_nodes(), 5))
    h1 = edge_conv(g, (h0, x0))
    assert h1.shape == (g.number_of_dst_nodes(), out_dim)


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["homo", "block-bipartite"], exclude=["zero-degree"])
)
@pytest.mark.parametrize("out_dim", [1, 2])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_dotgat_conv(g, idtype, out_dim, num_heads):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    dotgat = nn.DotGatConv(5, out_dim, num_heads)
    feat = F.randn((g.number_of_src_nodes(), 5))
    dotgat = dotgat.to(ctx)

    # test pickle
    th.save(dotgat, tmp_buffer)

    h = dotgat(g, feat)
    assert h.shape == (g.number_of_dst_nodes(), num_heads, out_dim)
    _, a = dotgat(g, feat, get_attention=True)
    assert a.shape == (g.num_edges(), num_heads, 1)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["bipartite"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_dim", [1, 2])
@pytest.mark.parametrize("num_heads", [1, 4])
def test_dotgat_conv_bi(g, idtype, out_dim, num_heads):
    g = g.astype(idtype).to(F.ctx())
    ctx = F.ctx()
    dotgat = nn.DotGatConv((5, 5), out_dim, num_heads)
    feat = (
        F.randn((g.number_of_src_nodes(), 5)),
        F.randn((g.number_of_dst_nodes(), 5)),
    )
    dotgat = dotgat.to(ctx)
    h = dotgat(g, feat)
    assert h.shape == (g.number_of_dst_nodes(), num_heads, out_dim)
    _, a = dotgat(g, feat, get_attention=True)
    assert a.shape == (g.num_edges(), num_heads, 1)


@pytest.mark.parametrize("out_dim", [1, 2])
def test_dense_cheb_conv(out_dim):
    for k in range(1, 4):
        ctx = F.ctx()
        g = dgl.from_scipy(sp.sparse.random(100, 100, density=0.1))
        g = g.to(F.ctx())
        adj = g.adj_external(transpose=True, ctx=ctx).to_dense()
        cheb = nn.ChebConv(5, out_dim, k, None)
        dense_cheb = nn.DenseChebConv(5, out_dim, k)
        # for i in range(len(cheb.fc)):
        #    dense_cheb.W.data[i] = cheb.fc[i].weight.data.t()
        dense_cheb.W.data = cheb.linear.weight.data.transpose(-1, -2).view(
            k, 5, out_dim
        )
        if cheb.linear.bias is not None:
            dense_cheb.bias.data = cheb.linear.bias.data
        feat = F.randn((100, 5))
        cheb = cheb.to(ctx)
        dense_cheb = dense_cheb.to(ctx)
        out_cheb = cheb(g, feat, [2.0])
        out_dense_cheb = dense_cheb(adj, feat, 2.0)
        print(k, out_cheb, out_dense_cheb)
        assert F.allclose(out_cheb, out_dense_cheb)


def test_sequential():
    ctx = F.ctx()

    # Test single graph
    class ExampleLayer(th.nn.Module):
        def __init__(self):
            super().__init__()

        def forward(self, graph, n_feat, e_feat):
            graph = graph.local_var()
            graph.ndata["h"] = n_feat
            graph.update_all(fn.copy_u("h", "m"), fn.sum("m", "h"))
            n_feat += graph.ndata["h"]
            graph.apply_edges(fn.u_add_v("h", "h", "e"))
            e_feat += graph.edata["e"]
            return n_feat, e_feat

    g = dgl.graph([])
    g.add_nodes(3)
    g.add_edges([0, 1, 2, 0, 1, 2, 0, 1, 2], [0, 0, 0, 1, 1, 1, 2, 2, 2])
    g = g.to(F.ctx())
    net = nn.Sequential(ExampleLayer(), ExampleLayer(), ExampleLayer())
    n_feat = F.randn((3, 4))
    e_feat = F.randn((9, 4))
    net = net.to(ctx)
    n_feat, e_feat = net(g, n_feat, e_feat)
    assert n_feat.shape == (3, 4)
    assert e_feat.shape == (9, 4)

    # Test multiple graph
    class ExampleLayer(th.nn.Module):
        def __init__(self):
            super().__init__()

        def forward(self, graph, n_feat):
            graph = graph.local_var()
            graph.ndata["h"] = n_feat
            graph.update_all(fn.copy_u("h", "m"), fn.sum("m", "h"))
            n_feat += graph.ndata["h"]
            return n_feat.view(graph.num_nodes() // 2, 2, -1).sum(1)

    g1 = dgl.from_networkx(nx.erdos_renyi_graph(32, 0.05)).to(ctx)
    g2 = dgl.from_networkx(nx.erdos_renyi_graph(16, 0.2)).to(ctx)
    g3 = dgl.from_networkx(nx.erdos_renyi_graph(8, 0.8)).to(ctx)
    net = nn.Sequential(ExampleLayer(), ExampleLayer(), ExampleLayer())
    net = net.to(ctx)
    n_feat = F.randn((32, 4))
    n_feat = net([g1, g2, g3], n_feat)
    assert n_feat.shape == (4, 4)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
def test_atomic_conv(g, idtype):
    g = g.astype(idtype).to(F.ctx())
    aconv = nn.AtomicConv(
        interaction_cutoffs=F.tensor([12.0, 12.0]),
        rbf_kernel_means=F.tensor([0.0, 2.0]),
        rbf_kernel_scaling=F.tensor([4.0, 4.0]),
        features_to_use=F.tensor([6.0, 8.0]),
    )

    ctx = F.ctx()
    if F.gpu_ctx():
        aconv = aconv.to(ctx)

    feat = F.randn((g.num_nodes(), 1))
    dist = F.randn((g.num_edges(), 1))

    h = aconv(g, feat, dist)

    # current we only do shape check
    assert h.shape[-1] == 4


@parametrize_idtype
@pytest.mark.parametrize(
    "g", get_cases(["homo", "bipartite"], exclude=["zero-degree"])
)
@pytest.mark.parametrize("out_dim", [1, 3])
def test_cf_conv(g, idtype, out_dim):
    g = g.astype(idtype).to(F.ctx())
    cfconv = nn.CFConv(
        node_in_feats=2, edge_in_feats=3, hidden_feats=2, out_feats=out_dim
    )

    ctx = F.ctx()
    if F.gpu_ctx():
        cfconv = cfconv.to(ctx)

    src_feats = F.randn((g.number_of_src_nodes(), 2))
    edge_feats = F.randn((g.num_edges(), 3))
    h = cfconv(g, src_feats, edge_feats)
    # current we only do shape check
    assert h.shape[-1] == out_dim

    # case for bipartite graphs
    dst_feats = F.randn((g.number_of_dst_nodes(), 3))
    h = cfconv(g, (src_feats, dst_feats), edge_feats)
    # current we only do shape check
    assert h.shape[-1] == out_dim


def myagg(alist, dsttype):
    rst = alist[0]
    for i in range(1, len(alist)):
        rst = rst + (i + 1) * alist[i]
    return rst


@parametrize_idtype
@pytest.mark.parametrize("agg", ["sum", "max", "min", "mean", "stack", myagg])
@pytest.mark.parametrize("canonical_keys", [False, True])
def test_hetero_conv(agg, idtype, canonical_keys):
    g = dgl.heterograph(
        {
            ("user", "follows", "user"): ([0, 0, 2, 1], [1, 2, 1, 3]),
            ("user", "plays", "game"): ([0, 0, 0, 1, 2], [0, 2, 3, 0, 2]),
            ("store", "sells", "game"): ([0, 0, 1, 1], [0, 3, 1, 2]),
        },
        idtype=idtype,
        device=F.ctx(),
    )
    if not canonical_keys:
        conv = nn.HeteroGraphConv(
            {
                "follows": nn.GraphConv(2, 3, allow_zero_in_degree=True),
                "plays": nn.GraphConv(2, 4, allow_zero_in_degree=True),
                "sells": nn.GraphConv(3, 4, allow_zero_in_degree=True),
            },
            agg,
        )
    else:
        conv = nn.HeteroGraphConv(
            {
                ("user", "follows", "user"): nn.GraphConv(
                    2, 3, allow_zero_in_degree=True
                ),
                ("user", "plays", "game"): nn.GraphConv(
                    2, 4, allow_zero_in_degree=True
                ),
                ("store", "sells", "game"): nn.GraphConv(
                    3, 4, allow_zero_in_degree=True
                ),
            },
            agg,
        )

    conv = conv.to(F.ctx())

    # test pickle
    th.save(conv, tmp_buffer)

    uf = F.randn((4, 2))
    gf = F.randn((4, 4))
    sf = F.randn((2, 3))

    h = conv(g, {"user": uf, "game": gf, "store": sf})
    assert set(h.keys()) == {"user", "game"}
    if agg != "stack":
        assert h["user"].shape == (4, 3)
        assert h["game"].shape == (4, 4)
    else:
        assert h["user"].shape == (4, 1, 3)
        assert h["game"].shape == (4, 2, 4)

    block = dgl.to_block(
        g.to(F.cpu()), {"user": [0, 1, 2, 3], "game": [0, 1, 2, 3], "store": []}
    ).to(F.ctx())
    h = conv(
        block,
        (
            {"user": uf, "game": gf, "store": sf},
            {"user": uf, "game": gf, "store": sf[0:0]},
        ),
    )
    assert set(h.keys()) == {"user", "game"}
    if agg != "stack":
        assert h["user"].shape == (4, 3)
        assert h["game"].shape == (4, 4)
    else:
        assert h["user"].shape == (4, 1, 3)
        assert h["game"].shape == (4, 2, 4)

    h = conv(block, {"user": uf, "game": gf, "store": sf})
    assert set(h.keys()) == {"user", "game"}
    if agg != "stack":
        assert h["user"].shape == (4, 3)
        assert h["game"].shape == (4, 4)
    else:
        assert h["user"].shape == (4, 1, 3)
        assert h["game"].shape == (4, 2, 4)

    # test with mod args
    class MyMod(th.nn.Module):
        def __init__(self, s1, s2):
            super(MyMod, self).__init__()
            self.carg1 = 0
            self.carg2 = 0
            self.s1 = s1
            self.s2 = s2

        def forward(self, g, h, arg1=None, *, arg2=None):
            if arg1 is not None:
                self.carg1 += 1
            if arg2 is not None:
                self.carg2 += 1
            return th.zeros((g.number_of_dst_nodes(), self.s2))

    mod1 = MyMod(2, 3)
    mod2 = MyMod(2, 4)
    mod3 = MyMod(3, 4)
    conv = nn.HeteroGraphConv(
        {"follows": mod1, "plays": mod2, "sells": mod3}, agg
    )
    conv = conv.to(F.ctx())
    mod_args = {"follows": (1,), "plays": (1,)}
    mod_kwargs = {"sells": {"arg2": "abc"}}
    h = conv(
        g,
        {"user": uf, "game": gf, "store": sf},
        mod_args=mod_args,
        mod_kwargs=mod_kwargs,
    )
    assert mod1.carg1 == 1
    assert mod1.carg2 == 0
    assert mod2.carg1 == 1
    assert mod2.carg2 == 0
    assert mod3.carg1 == 0
    assert mod3.carg2 == 1

    # conv on graph without any edges
    for etype in g.etypes:
        g = dgl.remove_edges(g, g.edges(form="eid", etype=etype), etype=etype)
    assert g.num_edges() == 0
    h = conv(g, {"user": uf, "game": gf, "store": sf})
    assert set(h.keys()) == {"user", "game"}

    block = dgl.to_block(
        g.to(F.cpu()), {"user": [0, 1, 2, 3], "game": [0, 1, 2, 3], "store": []}
    ).to(F.ctx())
    h = conv(
        block,
        (
            {"user": uf, "game": gf, "store": sf},
            {"user": uf, "game": gf, "store": sf[0:0]},
        ),
    )
    assert set(h.keys()) == {"user", "game"}


@pytest.mark.parametrize("out_dim", [1, 2, 100])
def test_hetero_linear(out_dim):
    in_feats = {
        "user": F.randn((2, 1)),
        ("user", "follows", "user"): F.randn((3, 2)),
    }

    layer = nn.HeteroLinear(
        {"user": 1, ("user", "follows", "user"): 2}, out_dim
    )
    layer = layer.to(F.ctx())
    out_feats = layer(in_feats)
    assert out_feats["user"].shape == (2, out_dim)
    assert out_feats[("user", "follows", "user")].shape == (3, out_dim)


@pytest.mark.parametrize("out_dim", [1, 2, 100])
def test_hetero_embedding(out_dim):
    layer = nn.HeteroEmbedding(
        {"user": 2, ("user", "follows", "user"): 3}, out_dim
    )
    layer = layer.to(F.ctx())

    embeds = layer.weight
    assert embeds["user"].shape == (2, out_dim)
    assert embeds[("user", "follows", "user")].shape == (3, out_dim)

    layer.reset_parameters()
    embeds = layer.weight
    assert embeds["user"].shape == (2, out_dim)
    assert embeds[("user", "follows", "user")].shape == (3, out_dim)

    embeds = layer(
        {
            "user": F.tensor([0], dtype=F.int64),
            ("user", "follows", "user"): F.tensor([0, 2], dtype=F.int64),
        }
    )
    assert embeds["user"].shape == (1, out_dim)
    assert embeds[("user", "follows", "user")].shape == (2, out_dim)


@parametrize_idtype
@pytest.mark.parametrize("g", get_cases(["homo"], exclude=["zero-degree"]))
@pytest.mark.parametrize("out_dim", [1, 2])
def test_gnnexplainer(g, idtype, out_dim):
    g = g.astype(idtype).to(F.ctx())
    feat = F.randn((g.num_nodes(), 5))

    class Model(th.nn.Module):
        def __init__(self, in_feats, out_feats, graph=False):
            super(Model, self).__init__()
            self.linear = th.nn.Linear(in_feats, out_feats)
            if graph:
                self.pool = nn.AvgPooling()
            else:
                self.pool = None

        def forward(self, graph, feat, eweight=None):
            with graph.local_scope():
                feat = self.linear(feat)
                graph.ndata["h"] = feat
                if eweight is None:
                    graph.update_all(fn.copy_u("h", "m"), fn.sum("m", "h"))
                else:
                    graph.edata["w"] = eweight
                    graph.update_all(
                        fn.u_mul_e("h", "w", "m"), fn.sum("m", "h")
                    )

                if self.pool:
                    return self.pool(graph, graph.ndata["h"])
                else:
                    return graph.ndata["h"]

    # Explain node prediction
    model = Model(5, out_dim)
    model = model.to(F.ctx())
    explainer = nn.GNNExplainer(model, num_hops=1)
    new_center, sg, feat_mask, edge_mask = explainer.explain_node(0, g, feat)

    # Explain graph prediction
    model = Model(5, out_dim, graph=True)
    model = model.to(F.ctx())
    explainer = nn.GNNExplainer(model, num_hops=1)
    feat_mask, edge_mask = explainer.explain_graph(g, feat)


@pytest.mark.parametrize("g", get_cases(["hetero"], exclude=["zero-degree"]))
@pytest.mark.parametrize("idtype", [F.int64])
@pytest.mark.parametrize("input_dim", [5])
@pytest.mark.parametrize("output_dim", [1, 2])
def test_heterognnexplainer(g, idtype, input_dim, output_dim):
    g = g.astype(idtype).to(F.ctx())
    device = g.device

    # add self-loop and reverse edges
    transform1 = dgl.transforms.AddSelfLoop(new_etypes=True)
    g = transform1(g)
    transform2 = dgl.transforms.AddReverse(copy_edata=True)
    g = transform2(g)

    feat = {
        ntype: th.zeros((g.num_nodes(ntype), input_dim), device=device)
        for ntype in g.ntypes
    }

    class Model(th.nn.Module):
        def __init__(self, in_dim, num_classes, canonical_etypes, graph=False):
            super(Model, self).__init__()
            self.graph = graph
            self.etype_weights = th.nn.ModuleDict(
                {
                    "_".join(c_etype): th.nn.Linear(in_dim, num_classes)
                    for c_etype in canonical_etypes
                }
            )

        def forward(self, graph, feat, eweight=None):
            with graph.local_scope():
                c_etype_func_dict = {}
                for c_etype in graph.canonical_etypes:
                    src_type, etype, dst_type = c_etype
                    wh = self.etype_weights["_".join(c_etype)](feat[src_type])
                    graph.nodes[src_type].data[f"h_{c_etype}"] = wh
                    if eweight is None:
                        c_etype_func_dict[c_etype] = (
                            fn.copy_u(f"h_{c_etype}", "m"),
                            fn.mean("m", "h"),
                        )
                    else:
                        graph.edges[c_etype].data["w"] = eweight[c_etype]
                        c_etype_func_dict[c_etype] = (
                            fn.u_mul_e(f"h_{c_etype}", "w", "m"),
                            fn.mean("m", "h"),
                        )
                graph.multi_update_all(c_etype_func_dict, "sum")
                if self.graph:
                    hg = 0
                    for ntype in graph.ntypes:
                        if graph.num_nodes(ntype):
                            hg = hg + dgl.mean_nodes(graph, "h", ntype=ntype)

                    return hg
                else:
                    return graph.ndata["h"]

    # Explain node prediction
    model = Model(input_dim, output_dim, g.canonical_etypes)
    model = model.to(F.ctx())
    ntype = g.ntypes[0]
    explainer = nn.explain.HeteroGNNExplainer(model, num_hops=1)
    new_center, sg, feat_mask, edge_mask = explainer.explain_node(
        ntype, 0, g, feat
    )

    # Explain graph prediction
    model = Model(input_dim, output_dim, g.canonical_etypes, graph=True)
    model = model.to(F.ctx())
    explainer = nn.explain.HeteroGNNExplainer(model, num_hops=1)
    feat_mask, edge_mask = explainer.explain_graph(g, feat)


@parametrize_idtype
@pytest.mark.parametrize(
    "g",
    get_cases(
        ["homo"],
        exclude=[
            "zero-degree",
            "homo-zero-degree",
            "has_feature",
            "has_scalar_e_feature",
            "row_sorted",
            "col_sorted",
            "batched",
        ],
    ),
)
@pytest.mark.parametrize("n_classes", [2])
def test_subgraphx(g, idtype, n_classes):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    feat = F.randn((g.num_nodes(), 5))

    class Model(th.nn.Module):
        def __init__(self, in_dim, n_classes):
            super().__init__()
            self.conv = nn.GraphConv(in_dim, n_classes)
            self.pool = nn.AvgPooling()

        def forward(self, g, h):
            h = th.nn.functional.relu(self.conv(g, h))
            return self.pool(g, h)

    model = Model(feat.shape[1], n_classes)
    model = model.to(ctx)
    explainer = nn.SubgraphX(
        model, num_hops=1, shapley_steps=20, num_rollouts=5, coef=2.0
    )
    explainer.explain_graph(g, feat, target_class=0)


@pytest.mark.parametrize("g", get_cases(["hetero"], exclude=["zero-degree"]))
@pytest.mark.parametrize("idtype", [F.int64])
@pytest.mark.parametrize("input_dim", [5])
@pytest.mark.parametrize("n_classes", [2])
def test_heterosubgraphx(g, idtype, input_dim, n_classes):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    device = g.device

    # add self-loop and reverse edges
    transform1 = dgl.transforms.AddSelfLoop(new_etypes=True)
    g = transform1(g)
    transform2 = dgl.transforms.AddReverse(copy_edata=True)
    g = transform2(g)

    feat = {
        ntype: th.zeros((g.num_nodes(ntype), input_dim), device=device)
        for ntype in g.ntypes
    }

    class Model(th.nn.Module):
        def __init__(self, in_dim, n_classes, canonical_etypes):
            super(Model, self).__init__()
            self.etype_weights = th.nn.ModuleDict(
                {
                    "_".join(c_etype): th.nn.Linear(in_dim, n_classes)
                    for c_etype in canonical_etypes
                }
            )

        def forward(self, graph, feat):
            with graph.local_scope():
                c_etype_func_dict = {}
                for c_etype in graph.canonical_etypes:
                    src_type, etype, dst_type = c_etype
                    wh = self.etype_weights["_".join(c_etype)](feat[src_type])
                    graph.nodes[src_type].data[f"h_{c_etype}"] = wh
                    c_etype_func_dict[c_etype] = (
                        fn.copy_u(f"h_{c_etype}", "m"),
                        fn.mean("m", "h"),
                    )
                graph.multi_update_all(c_etype_func_dict, "sum")
                hg = 0
                for ntype in graph.ntypes:
                    if graph.num_nodes(ntype):
                        hg = hg + dgl.mean_nodes(graph, "h", ntype=ntype)

                return hg

    model = Model(input_dim, n_classes, g.canonical_etypes)
    model = model.to(ctx)
    explainer = nn.HeteroSubgraphX(
        model, num_hops=1, shapley_steps=20, num_rollouts=5, coef=2.0
    )
    explainer.explain_graph(g, feat, target_class=0)


@parametrize_idtype
@pytest.mark.parametrize(
    "g",
    get_cases(
        ["homo"],
        exclude=[
            "zero-degree",
            "homo-zero-degree",
            "has_feature",
            "has_scalar_e_feature",
            "row_sorted",
            "col_sorted",
        ],
    ),
)
@pytest.mark.parametrize("n_classes", [2])
def test_pgexplainer(g, idtype, n_classes):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    feat = F.randn((g.num_nodes(), 5))
    g.ndata["attr"] = feat

    # add reverse edges
    transform = dgl.transforms.AddReverse(copy_edata=True)
    g = transform(g)

    class Model(th.nn.Module):
        def __init__(self, in_feats, out_feats, graph=False):
            super(Model, self).__init__()
            self.graph = graph
            self.conv = nn.GraphConv(in_feats, out_feats)
            self.fc = th.nn.Linear(out_feats, out_feats)
            th.nn.init.xavier_uniform_(self.fc.weight)

        def forward(self, g, h, embed=False, edge_weight=None):
            h = self.conv(g, h, edge_weight=edge_weight)

            if not self.graph or embed:
                return h

            with g.local_scope():
                g.ndata["h"] = h
                hg = dgl.mean_nodes(g, "h")
                return self.fc(hg)

    # graph explainer
    model = Model(feat.shape[1], n_classes, graph=True)
    model = model.to(ctx)
    explainer = nn.PGExplainer(model, n_classes)
    explainer.train_step(g, g.ndata["attr"], 5.0)

    probs, edge_weight = explainer.explain_graph(g, feat)

    # node explainer
    model = Model(feat.shape[1], n_classes, graph=False)
    model = model.to(ctx)
    explainer = nn.PGExplainer(
        model, n_classes, num_hops=1, explain_graph=False
    )
    explainer.train_step_node(0, g, g.ndata["attr"], 5.0)
    explainer.train_step_node([0, 1], g, g.ndata["attr"], 5.0)
    explainer.train_step_node(th.tensor(0), g, g.ndata["attr"], 5.0)
    explainer.train_step_node(th.tensor([0, 1]), g, g.ndata["attr"], 5.0)

    probs, edge_weight, bg, inverse_indices = explainer.explain_node(0, g, feat)
    probs, edge_weight, bg, inverse_indices = explainer.explain_node(
        [0, 1], g, feat
    )
    probs, edge_weight, bg, inverse_indices = explainer.explain_node(
        th.tensor(0), g, feat
    )
    probs, edge_weight, bg, inverse_indices = explainer.explain_node(
        th.tensor([0, 1]), g, feat
    )


@pytest.mark.parametrize("g", get_cases(["hetero"]))
@pytest.mark.parametrize("idtype", [F.int64])
@pytest.mark.parametrize("input_dim", [5])
@pytest.mark.parametrize("n_classes", [2])
def test_heteropgexplainer(g, idtype, input_dim, n_classes):
    ctx = F.ctx()
    g = g.astype(idtype).to(ctx)
    feat = {
        ntype: F.randn((g.num_nodes(ntype), input_dim)) for ntype in g.ntypes
    }

    # add self-loop and reverse edges
    transform1 = dgl.transforms.AddSelfLoop(new_etypes=True)
    g = transform1(g)
    transform2 = dgl.transforms.AddReverse(copy_edata=True)
    g = transform2(g)

    class Model(th.nn.Module):
        def __init__(
            self, in_feats, embed_dim, out_feats, canonical_etypes, graph=True
        ):
            super(Model, self).__init__()
            self.graph = graph
            self.conv = nn.HeteroGraphConv(
                {
                    c_etype: nn.GraphConv(in_feats, embed_dim)
                    for c_etype in canonical_etypes
                }
            )
            self.fc = th.nn.Linear(embed_dim, out_feats)

        def forward(self, g, h, embed=False, edge_weight=None):
            if edge_weight is not None:
                mod_kwargs = {
                    etype: {"edge_weight": mask}
                    for etype, mask in edge_weight.items()
                }
                h = self.conv(g, h, mod_kwargs=mod_kwargs)
            else:
                h = self.conv(g, h)

            if not self.graph or embed:
                return h

            with g.local_scope():
                g.ndata["h"] = h
                hg = 0
                for ntype in g.ntypes:
                    hg = hg + dgl.mean_nodes(g, "h", ntype=ntype)
                return self.fc(hg)

    embed_dim = input_dim

    # graph explainer
    model = Model(
        input_dim, embed_dim, n_classes, g.canonical_etypes, graph=True
    )
    model = model.to(ctx)
    explainer = nn.HeteroPGExplainer(model, embed_dim)
    explainer.train_step(g, feat, 5.0)

    probs, edge_weight = explainer.explain_graph(g, feat)

    # node explainer
    model = Model(
        input_dim, embed_dim, n_classes, g.canonical_etypes, graph=False
    )
    model = model.to(ctx)
    explainer = nn.HeteroPGExplainer(
        model, embed_dim, num_hops=1, explain_graph=False
    )
    explainer.train_step_node({g.ntypes[0]: [0]}, g, feat, 5.0)
    explainer.train_step_node({g.ntypes[0]: th.tensor([0, 1])}, g, feat, 5.0)

    probs, edge_weight, bg, inverse_indices = explainer.explain_node(
        {g.ntypes[0]: [0]}, g, feat
    )
    probs, edge_weight, bg, inverse_indices = explainer.explain_node(
        {g.ntypes[0]: th.tensor([0, 1])}, g, feat
    )


def test_jumping_knowledge():
    ctx = F.ctx()
    num_layers = 2
    num_nodes = 3
    num_feats = 4

    feat_list = [
        th.randn((num_nodes, num_feats)).to(ctx) for _ in range(num_layers)
    ]

    model = nn.JumpingKnowledge("cat").to(ctx)
    model.reset_parameters()
    assert model(feat_list).shape == (num_nodes, num_layers * num_feats)

    model = nn.JumpingKnowledge("max").to(ctx)
    model.reset_parameters()
    assert model(feat_list).shape == (num_nodes, num_feats)

    model = nn.JumpingKnowledge("lstm", num_feats, num_layers).to(ctx)
    model.reset_parameters()
    assert model(feat_list).shape == (num_nodes, num_feats)


@pytest.mark.parametrize("op", ["dot", "cos", "ele", "cat"])
def test_edge_predictor(op):
    ctx = F.ctx()
    num_pairs = 3
    in_feats = 4
    out_feats = 5
    h_src = th.randn((num_pairs, in_feats)).to(ctx)
    h_dst = th.randn((num_pairs, in_feats)).to(ctx)

    pred = nn.EdgePredictor(op)
    if op in ["dot", "cos"]:
        assert pred(h_src, h_dst).shape == (num_pairs, 1)
    elif op == "ele":
        assert pred(h_src, h_dst).shape == (num_pairs, in_feats)
    else:
        assert pred(h_src, h_dst).shape == (num_pairs, 2 * in_feats)
    pred = nn.EdgePredictor(op, in_feats, out_feats, bias=True).to(ctx)
    assert pred(h_src, h_dst).shape == (num_pairs, out_feats)


def test_ke_score_funcs():
    ctx = F.ctx()
    num_edges = 30
    num_rels = 3
    nfeats = 4

    h_src = th.randn((num_edges, nfeats)).to(ctx)
    h_dst = th.randn((num_edges, nfeats)).to(ctx)
    rels = th.randint(low=0, high=num_rels, size=(num_edges,)).to(ctx)

    score_func = nn.TransE(num_rels=num_rels, feats=nfeats).to(ctx)
    score_func.reset_parameters()
    score_func(h_src, h_dst, rels).shape == (num_edges)

    score_func = nn.TransR(
        num_rels=num_rels, rfeats=nfeats - 1, nfeats=nfeats
    ).to(ctx)
    score_func.reset_parameters()
    score_func(h_src, h_dst, rels).shape == (num_edges)


def test_twirls():
    g = dgl.graph(([0, 1, 2, 3, 2, 5], [1, 2, 3, 4, 0, 3]))
    feat = th.ones(6, 10)
    conv = nn.TWIRLSConv(10, 2, 128, prop_step=64)
    res = conv(g, feat)
    assert res.size() == (6, 2)


@pytest.mark.parametrize("feat_size", [4, 32])
@pytest.mark.parametrize(
    "regularizer,num_bases", [(None, None), ("basis", 4), ("bdd", 4)]
)
def test_typed_linear(feat_size, regularizer, num_bases):
    dev = F.ctx()
    num_types = 5
    lin = nn.TypedLinear(
        feat_size,
        feat_size * 2,
        5,
        regularizer=regularizer,
        num_bases=num_bases,
    ).to(dev)
    print(lin)
    x = th.randn(100, feat_size).to(dev)
    x_type = th.randint(0, 5, (100,)).to(dev)
    x_type_sorted, idx = th.sort(x_type)
    _, rev_idx = th.sort(idx)
    x_sorted = x[idx]

    # test unsorted
    y = lin(x, x_type)
    assert y.shape == (100, feat_size * 2)
    # test sorted
    y_sorted = lin(x_sorted, x_type_sorted, sorted_by_type=True)
    assert y_sorted.shape == (100, feat_size * 2)

    assert th.allclose(y, y_sorted[rev_idx], atol=1e-4, rtol=1e-4)


@parametrize_idtype
@pytest.mark.parametrize("in_size", [4])
@pytest.mark.parametrize("num_heads", [1])
def test_hgt(idtype, in_size, num_heads):
    dev = F.ctx()
    num_etypes = 5
    num_ntypes = 2
    head_size = in_size // num_heads

    g = dgl.from_scipy(sp.sparse.random(100, 100, density=0.01))
    g = g.astype(idtype).to(dev)
    etype = th.tensor([i % num_etypes for i in range(g.num_edges())]).to(dev)
    ntype = th.tensor([i % num_ntypes for i in range(g.num_nodes())]).to(dev)
    x = th.randn(g.num_nodes(), in_size).to(dev)

    m = nn.HGTConv(in_size, head_size, num_heads, num_ntypes, num_etypes).to(
        dev
    )

    y = m(g, x, ntype, etype)
    assert y.shape == (g.num_nodes(), head_size * num_heads)
    # presorted
    sorted_ntype, idx_nt = th.sort(ntype)
    sorted_etype, idx_et = th.sort(etype)
    _, rev_idx = th.sort(idx_nt)
    g.ndata["t"] = ntype
    g.ndata["x"] = x
    g.edata["t"] = etype
    sorted_g = dgl.reorder_graph(
        g,
        node_permute_algo="custom",
        edge_permute_algo="custom",
        permute_config={
            "nodes_perm": idx_nt.to(idtype),
            "edges_perm": idx_et.to(idtype),
        },
    )
    print(sorted_g.ndata["t"])
    print(sorted_g.edata["t"])
    sorted_x = sorted_g.ndata["x"]
    sorted_y = m(
        sorted_g, sorted_x, sorted_ntype, sorted_etype, presorted=False
    )
    assert sorted_y.shape == (g.num_nodes(), head_size * num_heads)
    # mini-batch
    train_idx = th.randperm(100, dtype=idtype)[:10]
    sampler = dgl.dataloading.NeighborSampler([-1])
    train_loader = dgl.dataloading.DataLoader(
        g, train_idx.to(dev), sampler, batch_size=8, device=dev, shuffle=True
    )
    (input_nodes, output_nodes, block) = next(iter(train_loader))
    block = block[0]
    x = x[input_nodes.to(th.long)]
    ntype = ntype[input_nodes.to(th.long)]
    edge = block.edata[dgl.EID]
    etype = etype[edge.to(th.long)]
    y = m(block, x, ntype, etype)
    assert y.shape == (block.number_of_dst_nodes(), head_size * num_heads)
    # TODO(minjie): enable the following check
    # assert th.allclose(y, sorted_y[rev_idx], atol=1e-4, rtol=1e-4)


@pytest.mark.parametrize("self_loop", [True, False])
@pytest.mark.parametrize("get_distances", [True, False])
def test_radius_graph(self_loop, get_distances):
    pos = th.tensor(
        [
            [0.1, 0.3, 0.4],
            [0.5, 0.2, 0.1],
            [0.7, 0.9, 0.5],
            [0.3, 0.2, 0.5],
            [0.2, 0.8, 0.2],
            [0.9, 0.2, 0.1],
            [0.7, 0.4, 0.4],
            [0.2, 0.1, 0.6],
            [0.5, 0.3, 0.5],
            [0.4, 0.2, 0.6],
        ]
    )

    rg = nn.RadiusGraph(0.3, self_loop=self_loop)

    if get_distances:
        g, dists = rg(pos, get_distances=get_distances)
    else:
        g = rg(pos)

    if self_loop:
        src_target = th.tensor(
            [
                0,
                0,
                1,
                2,
                3,
                3,
                3,
                3,
                3,
                4,
                5,
                6,
                6,
                7,
                7,
                7,
                8,
                8,
                8,
                8,
                9,
                9,
                9,
                9,
            ]
        )
        dst_target = th.tensor(
            [
                0,
                3,
                1,
                2,
                0,
                3,
                7,
                8,
                9,
                4,
                5,
                6,
                8,
                3,
                7,
                9,
                3,
                6,
                8,
                9,
                3,
                7,
                8,
                9,
            ]
        )

        if get_distances:
            dists_target = th.tensor(
                [
                    [0.0000],
                    [0.2449],
                    [0.0000],
                    [0.0000],
                    [0.2449],
                    [0.0000],
                    [0.1732],
                    [0.2236],
                    [0.1414],
                    [0.0000],
                    [0.0000],
                    [0.0000],
                    [0.2449],
                    [0.1732],
                    [0.0000],
                    [0.2236],
                    [0.2236],
                    [0.2449],
                    [0.0000],
                    [0.1732],
                    [0.1414],
                    [0.2236],
                    [0.1732],
                    [0.0000],
                ]
            )
    else:
        src_target = th.tensor([0, 3, 3, 3, 3, 6, 7, 7, 8, 8, 8, 9, 9, 9])
        dst_target = th.tensor([3, 0, 7, 8, 9, 8, 3, 9, 3, 6, 9, 3, 7, 8])

        if get_distances:
            dists_target = th.tensor(
                [
                    [0.2449],
                    [0.2449],
                    [0.1732],
                    [0.2236],
                    [0.1414],
                    [0.2449],
                    [0.1732],
                    [0.2236],
                    [0.2236],
                    [0.2449],
                    [0.1732],
                    [0.1414],
                    [0.2236],
                    [0.1732],
                ]
            )

    src, dst = g.edges()

    assert th.equal(src, src_target)
    assert th.equal(dst, dst_target)

    if get_distances:
        assert th.allclose(dists, dists_target, rtol=1e-03)


@parametrize_idtype
def test_group_rev_res(idtype):
    dev = F.ctx()

    num_nodes = 5
    num_edges = 20
    feats = 32
    groups = 2
    g = dgl.rand_graph(num_nodes, num_edges).to(dev)
    h = th.randn(num_nodes, feats).to(dev)
    conv = nn.GraphConv(feats // groups, feats // groups)
    model = nn.GroupRevRes(conv, groups).to(dev)
    result = model(g, h)
    result.sum().backward()


@pytest.mark.parametrize("in_size", [16, 32])
@pytest.mark.parametrize("hidden_size", [16, 32])
@pytest.mark.parametrize("out_size", [16, 32])
@pytest.mark.parametrize("edge_feat_size", [16, 10, 0])
def test_egnn_conv(in_size, hidden_size, out_size, edge_feat_size):
    dev = F.ctx()
    num_nodes = 5
    num_edges = 20
    g = dgl.rand_graph(num_nodes, num_edges).to(dev)
    h = th.randn(num_nodes, in_size).to(dev)
    x = th.randn(num_nodes, 3).to(dev)
    e = th.randn(num_edges, edge_feat_size).to(dev)
    model = nn.EGNNConv(in_size, hidden_size, out_size, edge_feat_size).to(dev)
    model(g, h, x, e)


@pytest.mark.parametrize("in_size", [16, 32])
@pytest.mark.parametrize("out_size", [16, 32])
@pytest.mark.parametrize(
    "aggregators",
    [
        ["mean", "max", "sum"],
        ["min", "std", "var"],
        ["moment3", "moment4", "moment5"],
    ],
)
@pytest.mark.parametrize(
    "scalers", [["identity"], ["amplification", "attenuation"]]
)
@pytest.mark.parametrize("delta", [2.5, 7.4])
@pytest.mark.parametrize("dropout", [0.0, 0.1])
@pytest.mark.parametrize("num_towers", [1, 4])
@pytest.mark.parametrize("edge_feat_size", [16, 0])
@pytest.mark.parametrize("residual", [True, False])
def test_pna_conv(
    in_size,
    out_size,
    aggregators,
    scalers,
    delta,
    dropout,
    num_towers,
    edge_feat_size,
    residual,
):
    dev = F.ctx()
    num_nodes = 5
    num_edges = 20
    g = dgl.rand_graph(num_nodes, num_edges).to(dev)
    h = th.randn(num_nodes, in_size).to(dev)
    e = th.randn(num_edges, edge_feat_size).to(dev)
    model = nn.PNAConv(
        in_size,
        out_size,
        aggregators,
        scalers,
        delta,
        dropout,
        num_towers,
        edge_feat_size,
        residual,
    ).to(dev)
    model(g, h, edge_feat=e)


@pytest.mark.parametrize("k", [3, 5])
@pytest.mark.parametrize("alpha", [0.0, 0.5, 1.0])
@pytest.mark.parametrize("norm_type", ["sym", "row"])
@pytest.mark.parametrize("clamp", [True, False])
@pytest.mark.parametrize("normalize", [True, False])
@pytest.mark.parametrize("reset", [True, False])
def test_label_prop(k, alpha, norm_type, clamp, normalize, reset):
    dev = F.ctx()
    num_nodes = 5
    num_edges = 20
    num_classes = 4
    g = dgl.rand_graph(num_nodes, num_edges).to(dev)
    labels = th.tensor([0, 2, 1, 3, 0]).long().to(dev)
    ml_labels = th.rand(num_nodes, num_classes).to(dev) > 0.7
    mask = th.tensor([0, 1, 1, 1, 0]).bool().to(dev)
    model = nn.LabelPropagation(k, alpha, norm_type, clamp, normalize, reset)
    model(g, labels, mask)
    # multi-label case
    model(g, ml_labels, mask)


@pytest.mark.parametrize("in_size", [16])
@pytest.mark.parametrize("out_size", [16, 32])
@pytest.mark.parametrize(
    "aggregators", [["mean", "max", "dir2-av"], ["min", "std", "dir1-dx"]]
)
@pytest.mark.parametrize("scalers", [["amplification", "attenuation"]])
@pytest.mark.parametrize("delta", [2.5])
@pytest.mark.parametrize("edge_feat_size", [16, 0])
def test_dgn_conv(
    in_size, out_size, aggregators, scalers, delta, edge_feat_size
):
    dev = F.ctx()
    num_nodes = 5
    num_edges = 20
    g = dgl.rand_graph(num_nodes, num_edges).to(dev)
    h = th.randn(num_nodes, in_size).to(dev)
    e = th.randn(num_edges, edge_feat_size).to(dev)
    transform = dgl.LapPE(k=3, feat_name="eig")
    g = transform(g)
    eig = g.ndata["eig"]
    model = nn.DGNConv(
        in_size,
        out_size,
        aggregators,
        scalers,
        delta,
        edge_feat_size=edge_feat_size,
    ).to(dev)
    model(g, h, edge_feat=e, eig_vec=eig)

    aggregators_non_eig = [
        aggr for aggr in aggregators if not aggr.startswith("dir")
    ]
    model = nn.DGNConv(
        in_size,
        out_size,
        aggregators_non_eig,
        scalers,
        delta,
        edge_feat_size=edge_feat_size,
    ).to(dev)
    model(g, h, edge_feat=e)


def test_DeepWalk():
    dev = F.ctx()
    g = dgl.graph(([0, 1, 2, 1, 2, 0], [1, 2, 0, 0, 1, 2]))
    model = nn.DeepWalk(
        g, emb_dim=8, walk_length=2, window_size=1, fast_neg=True, sparse=True
    )
    model = model.to(dev)
    dataloader = DataLoader(
        torch.arange(g.num_nodes()), batch_size=16, collate_fn=model.sample
    )
    optim = SparseAdam(model.parameters(), lr=0.01)
    walk = next(iter(dataloader)).to(dev)
    loss = model(walk)
    loss.backward()
    optim.step()

    model = nn.DeepWalk(
        g, emb_dim=8, walk_length=2, window_size=1, fast_neg=False, sparse=False
    )
    model = model.to(dev)
    dataloader = DataLoader(
        torch.arange(g.num_nodes()), batch_size=16, collate_fn=model.sample
    )
    optim = Adam(model.parameters(), lr=0.01)
    walk = next(iter(dataloader)).to(dev)
    loss = model(walk)
    loss.backward()
    optim.step()


@pytest.mark.parametrize("max_degree", [2, 6])
@pytest.mark.parametrize("embedding_dim", [8, 16])
@pytest.mark.parametrize("direction", ["in", "out", "both"])
def test_degree_encoder(max_degree, embedding_dim, direction):
    g1 = dgl.graph(
        (
            th.tensor([0, 0, 0, 1, 1, 2, 3, 3]),
            th.tensor([1, 2, 3, 0, 3, 0, 0, 1]),
        )
    )
    g2 = dgl.graph(
        (
            th.tensor([0, 1]),
            th.tensor([1, 0]),
        )
    )
    in_degree = pad_sequence(
        [g1.in_degrees(), g2.in_degrees()], batch_first=True
    )
    out_degree = pad_sequence(
        [g1.out_degrees(), g2.out_degrees()], batch_first=True
    )
    model = nn.DegreeEncoder(max_degree, embedding_dim, direction=direction)
    if direction == "in":
        de_g = model(in_degree)
    elif direction == "out":
        de_g = model(out_degree)
    elif direction == "both":
        de_g = model(th.stack((in_degree, out_degree)))
    assert de_g.shape == (2, 4, embedding_dim)


@parametrize_idtype
def test_MetaPath2Vec(idtype):
    dev = F.ctx()
    g = dgl.heterograph(
        {
            ("user", "uc", "company"): ([0, 0, 2, 1, 3], [1, 2, 1, 3, 0]),
            ("company", "cp", "product"): (
                [0, 0, 0, 1, 2, 3],
                [0, 2, 3, 0, 2, 1],
            ),
            ("company", "cu", "user"): ([1, 2, 1, 3, 0], [0, 0, 2, 1, 3]),
            ("product", "pc", "company"): (
                [0, 2, 3, 0, 2, 1],
                [0, 0, 0, 1, 2, 3],
            ),
        },
        idtype=idtype,
        device=dev,
    )
    model = nn.MetaPath2Vec(g, ["uc", "cu"], window_size=1)
    model = model.to(dev)
    embeds = model.node_embed.weight
    assert embeds.shape[0] == g.num_nodes()


@pytest.mark.parametrize("num_layer", [1, 4])
@pytest.mark.parametrize("k", [3, 5])
@pytest.mark.parametrize("lpe_dim", [4, 16])
@pytest.mark.parametrize("n_head", [2, 4])
@pytest.mark.parametrize("batch_norm", [True, False])
@pytest.mark.parametrize("num_post_layer", [0, 1, 2])
def test_LapPosEncoder(
    num_layer, k, lpe_dim, n_head, batch_norm, num_post_layer
):
    ctx = F.ctx()
    num_nodes = 4

    EigVals = th.randn((num_nodes, k)).to(ctx)
    EigVecs = th.randn((num_nodes, k)).to(ctx)

    model = nn.LapPosEncoder(
        "Transformer", num_layer, k, lpe_dim, n_head, batch_norm, num_post_layer
    ).to(ctx)
    assert model(EigVals, EigVecs).shape == (num_nodes, lpe_dim)

    model = nn.LapPosEncoder(
        "DeepSet",
        num_layer,
        k,
        lpe_dim,
        batch_norm=batch_norm,
        num_post_layer=num_post_layer,
    ).to(ctx)
    assert model(EigVals, EigVecs).shape == (num_nodes, lpe_dim)


@pytest.mark.parametrize("feat_size", [128, 512])
@pytest.mark.parametrize("num_heads", [8, 16])
@pytest.mark.parametrize("bias", [True, False])
@pytest.mark.parametrize("attn_bias_type", ["add", "mul"])
@pytest.mark.parametrize("attn_drop", [0.1, 0.5])
def test_BiasedMHA(feat_size, num_heads, bias, attn_bias_type, attn_drop):
    ndata = th.rand(16, 100, feat_size)
    attn_bias = th.rand(16, 100, 100, num_heads)
    attn_mask = th.rand(16, 100, 100) < 0.5

    net = nn.BiasedMHA(feat_size, num_heads, bias, attn_bias_type, attn_drop)
    out = net(ndata, attn_bias, attn_mask)

    assert out.shape == (16, 100, feat_size)


@pytest.mark.parametrize("edge_update", [True, False])
def test_EGTLayer(edge_update):
    batch_size = 16
    num_nodes = 100
    feat_size, edge_feat_size = 128, 32
    nfeat = th.rand(batch_size, num_nodes, feat_size)
    efeat = th.rand(batch_size, num_nodes, num_nodes, edge_feat_size)
    mask = (th.rand(batch_size, num_nodes, num_nodes) < 0.5) * -1e9

    net = nn.EGTLayer(
        feat_size=feat_size,
        edge_feat_size=edge_feat_size,
        num_heads=8,
        num_virtual_nodes=4,
        edge_update=edge_update,
    )

    if edge_update:
        out_nfeat, out_efeat = net(nfeat, efeat, mask)
        assert out_nfeat.shape == (batch_size, num_nodes, feat_size)
        assert out_efeat.shape == (
            batch_size,
            num_nodes,
            num_nodes,
            edge_feat_size,
        )
    else:
        out_nfeat = net(nfeat, efeat, mask)
        assert out_nfeat.shape == (batch_size, num_nodes, feat_size)


@pytest.mark.parametrize("attn_bias_type", ["add", "mul"])
@pytest.mark.parametrize("norm_first", [True, False])
def test_GraphormerLayer(attn_bias_type, norm_first):
    batch_size = 16
    num_nodes = 100
    feat_size = 512
    num_heads = 8
    nfeat = th.rand(batch_size, num_nodes, feat_size)
    attn_bias = th.rand(batch_size, num_nodes, num_nodes, num_heads)
    attn_mask = th.rand(batch_size, num_nodes, num_nodes) < 0.5

    net = nn.GraphormerLayer(
        feat_size=feat_size,
        hidden_size=2048,
        num_heads=num_heads,
        attn_bias_type=attn_bias_type,
        norm_first=norm_first,
        dropout=0.1,
        attn_dropout=0.1,
        activation=th.nn.ReLU(),
    )
    out = net(nfeat, attn_bias, attn_mask)

    assert out.shape == (batch_size, num_nodes, feat_size)


@pytest.mark.parametrize("max_len", [1, 2])
@pytest.mark.parametrize("feat_dim", [16])
@pytest.mark.parametrize("num_heads", [1, 8])
def test_PathEncoder(max_len, feat_dim, num_heads):
    dev = F.ctx()
    g = dgl.graph(
        (
            th.tensor([0, 0, 0, 1, 1, 2, 3, 3]),
            th.tensor([1, 2, 3, 0, 3, 0, 0, 1]),
        )
    ).to(dev)
    edge_feat = th.rand(g.num_edges(), feat_dim).to(dev)
    edge_feat = th.cat((edge_feat, th.zeros(1, 16).to(dev)), dim=0)
    dist, path = shortest_dist(g, root=None, return_paths=True)
    path_data = edge_feat[path[:, :, :max_len]]
    model = nn.PathEncoder(max_len, feat_dim, num_heads=num_heads).to(dev)
    bias = model(dist.unsqueeze(0), path_data.unsqueeze(0))
    assert bias.shape == (1, 4, 4, num_heads)


@pytest.mark.parametrize("max_dist", [1, 4])
@pytest.mark.parametrize("num_kernels", [4, 16])
@pytest.mark.parametrize("num_heads", [1, 8])
def test_SpatialEncoder(max_dist, num_kernels, num_heads):
    dev = F.ctx()
    # single graph encoding 3d
    num_nodes = 4
    coord = th.rand(1, num_nodes, 3).to(dev)
    node_type = th.tensor([[1, 0, 2, 1]]).to(dev)
    spatial_encoder = nn.SpatialEncoder3d(
        num_kernels=num_kernels, num_heads=num_heads, max_node_type=3
    ).to(dev)
    out = spatial_encoder(coord, node_type=node_type)
    assert out.shape == (1, num_nodes, num_nodes, num_heads)

    # encoding on a batch of graphs
    g1 = dgl.graph(
        (
            th.tensor([0, 0, 0, 1, 1, 2, 3, 3]),
            th.tensor([1, 2, 3, 0, 3, 0, 0, 1]),
        )
    ).to(dev)
    g2 = dgl.graph(
        (th.tensor([0, 1, 2, 3, 2, 5]), th.tensor([1, 2, 3, 4, 0, 3]))
    ).to(dev)
    bsz, max_num_nodes = 2, 6
    # 2d encoding
    dist = -th.ones((bsz, max_num_nodes, max_num_nodes), dtype=th.long).to(dev)
    dist[0, :4, :4] = shortest_dist(g1, root=None, return_paths=False)
    dist[1, :6, :6] = shortest_dist(g2, root=None, return_paths=False)
    model_1 = nn.SpatialEncoder(max_dist, num_heads=num_heads).to(dev)
    encoding = model_1(dist)
    assert encoding.shape == (bsz, max_num_nodes, max_num_nodes, num_heads)
    # 3d encoding
    coord = th.rand(bsz, max_num_nodes, 3).to(dev)
    node_type = th.randint(
        0,
        512,
        (
            bsz,
            max_num_nodes,
        ),
    ).to(dev)
    model_2 = nn.SpatialEncoder3d(num_kernels, num_heads=num_heads).to(dev)
    model_3 = nn.SpatialEncoder3d(
        num_kernels, num_heads=num_heads, max_node_type=512
    ).to(dev)
    encoding3d_1 = model_2(coord)
    encoding3d_2 = model_3(coord, node_type)
    assert encoding3d_1.shape == (bsz, max_num_nodes, max_num_nodes, num_heads)
    assert encoding3d_2.shape == (bsz, max_num_nodes, max_num_nodes, num_heads)


@pytest.mark.parametrize("residual", [True, False])
def test_conv_with_zero_nodes_bugfix_7894(residual):
    """Test for PR #7894 in DGL where HeteroGraphConv with zero nodes in a
    specific node type would cause an error due to empty tensors.
    This test ensures that GATConv, GATv2Conv, and EdgeGATConv can handle
    such cases without raising errors.
    """
    # Create a heterogeneous graph with zero nodes in the "tag" type
    user_item_src = torch.tensor([0, 1, 2])
    user_item_dst = torch.tensor([4, 5, 6])

    user_tag_src = torch.tensor([], dtype=torch.int64)
    user_tag_dst = torch.tensor([], dtype=torch.int64)

    num_nodes_dict = {
        "user": 5,
        "item": 10,
        "tag": 0,
    }

    data_dict = {
        ("user", "buys", "item"): (user_item_src, user_item_dst),
        ("user", "likes", "tag"): (user_tag_src, user_tag_dst),
    }

    g = dgl.heterograph(data_dict, num_nodes_dict=num_nodes_dict)

    feat_dim = 16
    node_features = {
        "user": torch.randn(num_nodes_dict["user"], feat_dim),
        "item": torch.randn(num_nodes_dict["item"], feat_dim),
        "tag": torch.randn(num_nodes_dict["tag"], feat_dim), 
    }
    edge_features = {
        ("user", "buys", "item"): torch.randn(g.num_edges(("user", "buys", "item")), feat_dim),
        ("user", "likes", "tag"): torch.randn(g.num_edges(("user", "likes", "tag")), feat_dim),
    }

    # Test GATConv with zero nodes in "tag" type
    conv = nn.HeteroGraphConv({
        ("user", "buys", "item"): nn.GATConv(16, 2, num_heads=2, residual=residual),
        ("user", "likes", "tag"): nn.GATConv(16, 2, num_heads=2, residual=residual),
    }, aggregate="sum")
    out = conv(g, node_features)
    assert out["item"].shape == (10, 2, 2)
    assert out["tag"].shape == (0, 2, 2)
    assert "user" not in out

    # Test GATv2Conv with zero nodes in "tag" type
    conv_v2 = nn.HeteroGraphConv({
        ("user", "buys", "item"): nn.GATv2Conv(16, 2, num_heads=2, residual=residual),
        ("user", "likes", "tag"): nn.GATv2Conv(16, 2, num_heads=2, residual=residual),
    }, aggregate="sum")
    out_v2 = conv_v2(g, node_features)
    assert out_v2["item"].shape == (10, 2, 2)
    assert out_v2["tag"].shape == (0, 2, 2)
    assert "user" not in out_v2

    # Test EdgeGATConv with zero nodes in "tag" type
    edge_conv = nn.HeteroGraphConv({
        ("user", "buys", "item"): nn.EdgeGATConv(16, 16, 2, num_heads=2, residual=residual),
        ("user", "likes", "tag"): nn.EdgeGATConv(16, 16, 2, num_heads=2, residual=residual),
    }, aggregate="sum")
    mod_kwargs = {
        "buys": {"edge_feat": edge_features[("user", "buys", "item")]},
        "likes": {"edge_feat": edge_features[("user", "likes", "tag")]},
    }
    out_edge = edge_conv(g, node_features, mod_kwargs=mod_kwargs)
    assert out_edge["item"].shape == (10, 2, 2)
    assert out_edge["tag"].shape == (0, 2, 2)
    assert "user" not in out_edge