bpo-43798: Add source location attributes to alias (GH-25324)

* Add source location attributes to alias.
* Move alias star construction to pegen helper.

Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>

4 files changed, 62 insertions, 7 deletions

diff --git a/Parser/Python.asdl b/Parser/Python.asdl
index ddc019da48..e224f5f484 100644
--- a/Parser/Python.asdl
+++ b/Parser/Python.asdl
@@ -124,6 +124,7 @@ module Python
 
     -- import name with optional 'as' alias.
     alias = (identifier name, identifier? asname)
+             attributes (int lineno, int col_offset, int? end_lineno, int? end_col_offset)
 
     withitem = (expr context_expr, expr? optional_vars)
 
diff --git a/Parser/parser.c b/Parser/parser.c
index cf8b624ce7..af0c088694 100644
--- a/Parser/parser.c
+++ b/Parser/parser.c
@@ -3310,6 +3310,15 @@ import_from_targets_rule(Parser *p)
     }
     asdl_alias_seq* _res = NULL;
     int _mark = p->mark;
+    if (p->mark == p->fill && _PyPegen_fill_token(p) < 0) {
+        p->error_indicator = 1;
+        D(p->level--);
+        return NULL;
+    }
+    int _start_lineno = p->tokens[_mark]->lineno;
+    UNUSED(_start_lineno); // Only used by EXTRA macro
+    int _start_col_offset = p->tokens[_mark]->col_offset;
+    UNUSED(_start_col_offset); // Only used by EXTRA macro
     { // '(' import_from_as_names ','? ')'
         if (p->error_indicator) {
             D(p->level--);
@@ -3377,7 +3386,16 @@ import_from_targets_rule(Parser *p)
         )
         {
             D(fprintf(stderr, "%*c+ import_from_targets[%d-%d]: %s succeeded!\n", p->level, ' ', _mark, p->mark, "'*'"));
-            _res = ( asdl_alias_seq * ) _PyPegen_singleton_seq ( p , CHECK ( alias_ty , _PyPegen_alias_for_star ( p ) ) );
+            Token *_token = _PyPegen_get_last_nonnwhitespace_token(p);
+            if (_token == NULL) {
+                D(p->level--);
+                return NULL;
+            }
+            int _end_lineno = _token->end_lineno;
+            UNUSED(_end_lineno); // Only used by EXTRA macro
+            int _end_col_offset = _token->end_col_offset;
+            UNUSED(_end_col_offset); // Only used by EXTRA macro
+            _res = ( asdl_alias_seq * ) _PyPegen_singleton_seq ( p , CHECK ( alias_ty , _PyPegen_alias_for_star ( p , EXTRA ) ) );
             if (_res == NULL && PyErr_Occurred()) {
                 p->error_indicator = 1;
                 D(p->level--);
@@ -3466,6 +3484,15 @@ import_from_as_name_rule(Parser *p)
     }
     alias_ty _res = NULL;
     int _mark = p->mark;
+    if (p->mark == p->fill && _PyPegen_fill_token(p) < 0) {
+        p->error_indicator = 1;
+        D(p->level--);
+        return NULL;
+    }
+    int _start_lineno = p->tokens[_mark]->lineno;
+    UNUSED(_start_lineno); // Only used by EXTRA macro
+    int _start_col_offset = p->tokens[_mark]->col_offset;
+    UNUSED(_start_col_offset); // Only used by EXTRA macro
     { // NAME ['as' NAME]
         if (p->error_indicator) {
             D(p->level--);
@@ -3481,7 +3508,16 @@ import_from_as_name_rule(Parser *p)
         )
         {
             D(fprintf(stderr, "%*c+ import_from_as_name[%d-%d]: %s succeeded!\n", p->level, ' ', _mark, p->mark, "NAME ['as' NAME]"));
-            _res = _PyAST_alias ( a -> v . Name . id , ( b ) ? ( ( expr_ty ) b ) -> v . Name . id : NULL , p -> arena );
+            Token *_token = _PyPegen_get_last_nonnwhitespace_token(p);
+            if (_token == NULL) {
+                D(p->level--);
+                return NULL;
+            }
+            int _end_lineno = _token->end_lineno;
+            UNUSED(_end_lineno); // Only used by EXTRA macro
+            int _end_col_offset = _token->end_col_offset;
+            UNUSED(_end_col_offset); // Only used by EXTRA macro
+            _res = _PyAST_alias ( a -> v . Name . id , ( b ) ? ( ( expr_ty ) b ) -> v . Name . id : NULL , EXTRA );
             if (_res == NULL && PyErr_Occurred()) {
                 p->error_indicator = 1;
                 D(p->level--);
@@ -3551,6 +3587,15 @@ dotted_as_name_rule(Parser *p)
     }
     alias_ty _res = NULL;
     int _mark = p->mark;
+    if (p->mark == p->fill && _PyPegen_fill_token(p) < 0) {
+        p->error_indicator = 1;
+        D(p->level--);
+        return NULL;
+    }
+    int _start_lineno = p->tokens[_mark]->lineno;
+    UNUSED(_start_lineno); // Only used by EXTRA macro
+    int _start_col_offset = p->tokens[_mark]->col_offset;
+    UNUSED(_start_col_offset); // Only used by EXTRA macro
     { // dotted_name ['as' NAME]
         if (p->error_indicator) {
             D(p->level--);
@@ -3566,7 +3611,16 @@ dotted_as_name_rule(Parser *p)
         )
         {
             D(fprintf(stderr, "%*c+ dotted_as_name[%d-%d]: %s succeeded!\n", p->level, ' ', _mark, p->mark, "dotted_name ['as' NAME]"));
-            _res = _PyAST_alias ( a -> v . Name . id , ( b ) ? ( ( expr_ty ) b ) -> v . Name . id : NULL , p -> arena );
+            Token *_token = _PyPegen_get_last_nonnwhitespace_token(p);
+            if (_token == NULL) {
+                D(p->level--);
+                return NULL;
+            }
+            int _end_lineno = _token->end_lineno;
+            UNUSED(_end_lineno); // Only used by EXTRA macro
+            int _end_col_offset = _token->end_col_offset;
+            UNUSED(_end_col_offset); // Only used by EXTRA macro
+            _res = _PyAST_alias ( a -> v . Name . id , ( b ) ? ( ( expr_ty ) b ) -> v . Name . id : NULL , EXTRA );
             if (_res == NULL && PyErr_Occurred()) {
                 p->error_indicator = 1;
                 D(p->level--);
diff --git a/Parser/pegen.c b/Parser/pegen.c
index 57759f7512..f841ace28e 100644
--- a/Parser/pegen.c
+++ b/Parser/pegen.c
@@ -1555,8 +1555,8 @@ _PyPegen_seq_count_dots(asdl_seq *seq)
 
 /* Creates an alias with '*' as the identifier name */
 alias_ty
-_PyPegen_alias_for_star(Parser *p)
-{
+_PyPegen_alias_for_star(Parser *p, int lineno, int col_offset, int end_lineno,
+                        int end_col_offset, PyArena *arena) {
     PyObject *str = PyUnicode_InternFromString("*");
     if (!str) {
         return NULL;
@@ -1565,7 +1565,7 @@ _PyPegen_alias_for_star(Parser *p)
         Py_DECREF(str);
         return NULL;
     }
-    return _PyAST_alias(str, NULL, p->arena);
+    return _PyAST_alias(str, NULL, lineno, col_offset, end_lineno, end_col_offset, arena);
 }
 
 /* Creates a new asdl_seq* with the identifiers of all the names in seq */
diff --git a/Parser/pegen.h b/Parser/pegen.h
index 53d8e5221b..f3e0876afb 100644
--- a/Parser/pegen.h
+++ b/Parser/pegen.h
@@ -237,7 +237,7 @@ asdl_seq *_PyPegen_seq_append_to_end(Parser *, asdl_seq *, void *);
 asdl_seq *_PyPegen_seq_flatten(Parser *, asdl_seq *);
 expr_ty _PyPegen_join_names_with_dot(Parser *, expr_ty, expr_ty);
 int _PyPegen_seq_count_dots(asdl_seq *);
-alias_ty _PyPegen_alias_for_star(Parser *);
+alias_ty _PyPegen_alias_for_star(Parser *, int, int, int, int, PyArena *);
 asdl_identifier_seq *_PyPegen_map_names_to_ids(Parser *, asdl_expr_seq *);
 CmpopExprPair *_PyPegen_cmpop_expr_pair(Parser *, cmpop_ty, expr_ty);
 asdl_int_seq *_PyPegen_get_cmpops(Parser *p, asdl_seq *);