Compare the source code of lambda and local functions

Author: Archmonger

src/reactpy/core/hooks.py

@@ -518,11 +518,30 @@ def strictly_equal(x: Any, y: Any) -> bool:
     - ``bytearray``
     - ``memoryview``
     """
+    # Return early if the objects are not the same type
     if type(x) is not type(y):
         return False
 
-    with contextlib.suppress(Exception):
-        if hasattr(x, "__eq__"):
+    # Compare the source code of lambda and local functions
+    if (
+        hasattr(x, "__qualname__")
+        and ("<lambda>" in x.__qualname__ or "<locals>" in x.__qualname__)
+        and hasattr(x, "__code__")
+    ):
+        if x.__qualname__ != y.__qualname__:
+            return False
+
+        return all(
+            getattr(x.__code__, attr) == getattr(y.__code__, attr)
+            for attr in dir(x.__code__)
+            if attr.startswith("co_")
+            and attr not in {"co_positions", "co_linetable", "co_lines"}
+        )
+
+    # Check via the `==` operator if possible
+    if hasattr(x, "__eq__"):
+        with contextlib.suppress(Exception):
             return x == y  # type: ignore
 
+    # Fallback to identity check
     return x is y

tests/test_core/test_hooks.py

@@ -1172,6 +1172,28 @@ def test_strictly_equal(x, y, result):
     assert strictly_equal(x, y) is result
 
 
+def test_strictly_equal_named_closures():
+    assert strictly_equal(lambda: "text", lambda: "text") is True
+    assert strictly_equal(lambda: "text", lambda: "not-text") is False
+
+    def x():
+        return "text"
+
+    def y():
+        return "not-text"
+
+    def generator():
+        def z():
+            return "text"
+
+        return z
+
+    assert strictly_equal(x, x) is True
+    assert strictly_equal(x, y) is False
+    assert strictly_equal(x, generator()) is False
+    assert strictly_equal(generator(), generator()) is True
+
+
 STRICT_EQUALITY_VALUE_CONSTRUCTORS = [
     lambda: "string-text",
     lambda: b"byte-text",