chore: import upstream snapshot with attribution

python/tests/workspace/executor/test_pipes.py

@@ -0,0 +1,77 @@
+# ========= Copyright 2026 @ Strukto.AI All Rights Reserved. =========
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ========= Copyright 2026 @ Strukto.AI All Rights Reserved. =========
+
+import pytest
+
+from mirage.io import IOResult
+from mirage.io.types import materialize
+from mirage.workspace.executor.pipes import handle_pipe
+from mirage.workspace.session import Session
+from mirage.workspace.types import ExecutionNode
+
+
+class FakeNode:
+
+    def __init__(self, text: str):
+        self.text = text
+
+
+@pytest.mark.asyncio
+async def test_handle_pipe_passes_empty_stdin_when_left_returns_none():
+    calls: list[dict] = []
+
+    async def execute_node(nd, _session, stdin, _call_stack=None):
+        stdin_was_none = stdin is None
+        materialized = await materialize(stdin)
+        calls.append({
+            "text": nd.text,
+            "stdin_was_none": stdin_was_none,
+            "stdin_bytes": materialized,
+        })
+        if nd.text == "left":
+            return (None, IOResult(stderr=b"boom", exit_code=1),
+                    ExecutionNode(command=nd.text, exit_code=1))
+        return (b"right-out", IOResult(exit_code=0),
+                ExecutionNode(command=nd.text, exit_code=0))
+
+    await handle_pipe(
+        execute_node,
+        [FakeNode("left"), FakeNode("right")],
+        [False],
+        Session(session_id="t"),
+        None,
+    )
+    right = next(c for c in calls if c["text"] == "right")
+    assert right["stdin_was_none"] is False
+    assert right["stdin_bytes"] == b""
+
+
+@pytest.mark.asyncio
+async def test_handle_pipe_threads_stdout_to_next_stdin():
+    seen: list[bytes] = []
+
+    async def execute_node(nd, _session, stdin, _call_stack=None):
+        seen.append(await materialize(stdin))
+        return (f"{nd.text}-out".encode(), IOResult(exit_code=0),
+                ExecutionNode(command=nd.text, exit_code=0))
+
+    await handle_pipe(
+        execute_node,
+        [FakeNode("a"), FakeNode("b")],
+        [False],
+        Session(session_id="t"),
+        None,
+    )
+    assert seen[0] == b""
+    assert seen[1] == b"a-out"