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sterliakov · sterliakov · commit 85d16bd8d811 · 2025-04-05T00:48:07.000+02:00
diff --git a/mypy/checker.py b/mypy/checker.py
@@ -5452,6 +5452,8 @@ def visit_match_stmt(self, s: MatchStmt) -> None:
                         pattern_map, else_map = conditional_types_to_typemaps(
                             named_subject, pattern_type.type, pattern_type.rest_type
                         )
+                        # Maybe the subject type can be inferred from constraints on
+                        # its attribute/item?
                         if pattern_map and named_subject in pattern_map:
                             pattern_map[s.subject] = pattern_map[named_subject]
                         if else_map and named_subject in else_map:

Original file line number	Diff line number	Diff line change
`@@ -5452,6 +5452,8 @@ def visit_match_stmt(self, s: MatchStmt) -> None:`
`5452`	`5452`	`pattern_map, else_map = conditional_types_to_typemaps(`
`5453`	`5453`	`named_subject, pattern_type.type, pattern_type.rest_type`
`5454`	`5454`	`)`
	`5455`	`+ # Maybe the subject type can be inferred from constraints on`
	`5456`	`+ # its attribute/item?`
`5455`	`5457`	`if pattern_map and named_subject in pattern_map:`
`5456`	`5458`	`pattern_map[s.subject] = pattern_map[named_subject]`
`5457`	`5459`	`if else_map and named_subject in else_map:`