bpo-45759: Better error messages for non-matching 'elif'/'else' state…

…ments (GH-29481)
python · thatbirdguythatuknownot · Nov 9, 2021 · Nov 9, 2021 · Nov 9, 2021 · Nov 9, 2021
commit 848296965becfeca012622e6ea33c987a5adb0c0
@@ -126,7 +126,6 @@ simple_stmt[stmt_ty] (memo):
     | &'nonlocal' nonlocal_stmt
 
 compound_stmt[stmt_ty]:
-    | invalid_compound_stmt
     | &('def' | '@' | ASYNC) function_def
     | &'if' if_stmt
     | &('class' | '@') class_def
@@ -1052,9 +1051,6 @@ func_type_comment[Token*]:
 # ========================= START OF INVALID RULES =======================
 
 # From here on, there are rules for invalid syntax with specialised error messages
-invalid_compound_stmt:
-    | a='elif' named_expression { RAISE_SYNTAX_ERROR_STARTING_FROM(a, "'elif' does not match an 'if' here") }
-    | a='else' named_expression { RAISE_SYNTAX_ERROR_STARTING_FROM(a, "'else' does not match a 'if'/'while'/'for' here") }
 invalid_arguments:
     | a=args ',' '*' { RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "iterable argument unpacking follows keyword argument unpacking") }
     | a=expression b=for_if_clauses ',' [args | expression for_if_clauses] {
@@ -1130,6 +1126,8 @@ invalid_del_stmt:
         RAISE_SYNTAX_ERROR_INVALID_TARGET(DEL_TARGETS, a) }
 invalid_block:
     | NEWLINE !INDENT { RAISE_INDENTATION_ERROR("expected an indented block") }
+    | a='elif' named_expression { RAISE_SYNTAX_ERROR_STARTING_FROM(a, "'elif' does not match an 'if' here") }
+    | a='else' named_expression { RAISE_SYNTAX_ERROR_STARTING_FROM(a, "'else' does not match a 'if'/'while'/'for' here") }
 invalid_comprehension:
     | ('[' | '(' | '{') a=starred_expression for_if_clauses {
         RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "iterable unpacking cannot be used in comprehension") }