chore: import upstream snapshot with attribution

python/dgl/base.py

@@ -0,0 +1,58 @@
+"""Module for base types and utilities."""
+from __future__ import absolute_import
+
+import warnings
+
+from ._ffi.base import DGLError  # pylint: disable=unused-import
+from ._ffi.function import _init_internal_api
+
+# A special symbol for selecting all nodes or edges.
+ALL = "__ALL__"
+# An alias for [:]
+SLICE_FULL = slice(None, None, None)
+# Reserved column names for storing parent node/edge types and IDs in flattened heterographs
+NTYPE = "_TYPE"
+NID = "_ID"
+ETYPE = "_TYPE"
+EID = "_ID"
+
+_INTERNAL_COLUMNS = {NTYPE, NID, ETYPE, EID}
+
+
+def is_internal_column(name):
+    """Return true if the column name is reversed by DGL."""
+    return name in _INTERNAL_COLUMNS
+
+
+def is_all(arg):
+    """Return true if the argument is a special symbol for all nodes or edges."""
+    return isinstance(arg, str) and arg == ALL
+
+
+# pylint: disable=invalid-name
+_default_formatwarning = warnings.formatwarning
+
+
+class DGLWarning(UserWarning):
+    """DGL Warning class."""
+
+
+# pylint: disable=unused-argument
+def dgl_warning_format(message, category, filename, lineno, line=None):
+    """Format DGL warnings."""
+    if isinstance(category, DGLWarning):
+        return "DGL Warning: {}\n".format(message)
+    else:
+        return _default_formatwarning(
+            message, category, filename, lineno, line=None
+        )
+
+
+def dgl_warning(message, category=DGLWarning, stacklevel=2):
+    """DGL warning wrapper that defaults to ``DGLWarning`` instead of ``UserWarning`` category."""
+    return warnings.warn(message, category=category, stacklevel=stacklevel)
+
+
+warnings.formatwarning = dgl_warning_format
+
+_init_internal_api()