Start implementing visit_MatchMapping()

Author: knutwannheden

rewrite/rewrite/python/_parser_visitor.py

@@ -926,7 +926,40 @@ def visit_MatchStar(self, node):
         )
 
     def visit_MatchMapping(self, node):
-        raise NotImplementedError("Implement visit_MatchMapping!")
+        return py.MatchCase(
+            random_id(),
+            self.__whitespace(),
+            Markers.EMPTY,
+            py.MatchCase.Pattern(
+                random_id(),
+                Space.EMPTY,
+                Markers.EMPTY,
+                py.MatchCase.Pattern.Kind.MAPPING,
+                JContainer(
+                    self.__source_before('{'),
+                    [self.__pad_list_element(py.MatchCase.Pattern(
+                        random_id(),
+                        Space.EMPTY,
+                        Markers.EMPTY,
+                        py.MatchCase.Pattern.Kind.KEY_VALUE,
+                        JContainer(
+                            Space.EMPTY,
+                            [
+                                self.__pad_right(self.__convert(node.keys[i]), self.__source_before(':')),
+                                self.__pad_right(self.__convert(node.patterns[i]), Space.EMPTY),
+                            ],
+                            Markers.EMPTY
+                        ),
+                        None
+                    ), last=i == len(node.patterns) - 1, end_delim='}') for i, e in
+                        enumerate(node.patterns)] if node.patterns else [],
+                    Markers.EMPTY
+                ),
+                None
+            ),
+            None,
+            None
+        )
 
     def visit_MatchClass(self, node):
         prefix = self.__whitespace()
@@ -1010,7 +1043,7 @@ def visit_MatchAs(self, node):
                 None,
                 None
             )
-        else:
+        elif node.pattern:
             return py.MatchCase(
                 random_id(),
                 self.__whitespace(),
@@ -1033,6 +1066,7 @@ def visit_MatchAs(self, node):
                 None,
                 None
             )
+        return self.__convert_name(node.name)
 
     def visit_MatchOr(self, node):
         return py.MatchCase(

rewrite/tests/python/py312/match_test.py

@@ -178,14 +178,28 @@ def test(x, value):
 
 
 def test_mapping():
+    # language=python
+    rewrite_run(
+        python(
+            """\
+            def test(x):
+                match x:
+                    case {"x": x, "y": y}:
+                        return x+y
+            """
+        )
+    )
+
+
+def test_mapping_with_rest():
     # language=python
     rewrite_run(
         python(
             """\
             def test(x):
                 match x:
                     case {"x": x, "y": y, **z}:
-                        return x+y+z
+                        return x+y+sum(z.values())
             """
         )
     )
@@ -211,7 +225,7 @@ def test_class(args):
         python(
             """\
             from abc import ABC
-            
+
             def test(x, y):
                 match x:
                     case ABC({0}):