gh-129958: Properly disallow newlines in format specs in single-quoted f-strings (GH-130063)

2025-04-18 13:30:04 +01:00
parent e01e582902
commit 2f8b08da47
4 changed files with 39 additions and 31 deletions
--- a/Parser/lexer/lexer.c
+++ b/Parser/lexer/lexer.c
@@ -1341,6 +1341,14 @@ f_string_middle:
            // it means that the format spec ends here and we should
            // return to the regular mode.
            if (in_format_spec && c == '\n') {
+                if (current_tok->f_string_quote_size == 1) {
+                    return MAKE_TOKEN(
+                        _PyTokenizer_syntaxerror(
+                            tok,
+                            "f-string: newlines are not allowed in format specifiers for single quoted f-strings"
+                        )
+                    );
+                }
                tok_backup(tok, c);
                TOK_GET_MODE(tok)->kind = TOK_REGULAR_MODE;
                current_tok->in_format_spec = 0;