[mypyc] feat: support constant folding in MessageBuilder.incompatible_argument

BobTheBuidler · BobTheBuidler · commit 88d5aacf23a5 · 2025-10-02T01:07:33.000Z
diff --git a/mypy/messages.py b/mypy/messages.py
@@ -808,10 +808,10 @@ def incompatible_argument(
                     )
                     arg_label = f'"{arg_name}"'
                 if isinstance(outer_context, IndexExpr) and isinstance(
-                    outer_context.index, StrExpr
+                    index := constant_fold_expr(outer_context.index, "unused"), str
                 ):
                     msg = 'Value of "{}" has incompatible type {}; expected {}'.format(
-                        outer_context.index.value,
+                        index,
                         quote_type_string(arg_type_str),
                         quote_type_string(expected_type_str),
                     )

Original file line number	Diff line number	Diff line change
`@@ -808,10 +808,10 @@ def incompatible_argument(`
`808`	`808`	`)`
`809`	`809`	`arg_label = f'"{arg_name}"'`
`810`	`810`	`if isinstance(outer_context, IndexExpr) and isinstance(`
`811`		`- outer_context.index, StrExpr`
	`811`	`+ index := constant_fold_expr(outer_context.index, "unused"), str`
`812`	`812`	`):`
`813`	`813`	`msg = 'Value of "{}" has incompatible type {}; expected {}'.format(`
`814`		`- outer_context.index.value,`
	`814`	`+ index,`
`815`	`815`	`quote_type_string(arg_type_str),`
`816`	`816`	`quote_type_string(expected_type_str),`
`817`	`817`	`)`