Simplify error & warning handling

tests/fuzz.py

@@ -26,7 +26,7 @@ def fuzz(buf):
         ast, errors, warnings = parser.parse(tokens)
 
         xml = XmlOutput()
-        if errors is None and len(ast.errors) == 0:
+        if errors is None and ast is not None:
             xml.emit(ast)
     except CompilerBugError as e:
         raise e

tests/sample_errors/menu_toplevel_attribute.blp

@@ -1,5 +1,5 @@
 using Gtk 4.0;
 
-menu {
+menu menu {
     not-allowed: true;
 }

tests/test_samples.py

@@ -57,8 +57,6 @@ class TestSamples(unittest.TestCase):
 
             if errors:
                 raise errors
-            if len(ast.errors):
-                raise MultipleErrors(ast.errors)
             if len(warnings):
                 raise MultipleErrors(warnings)
 
@@ -94,8 +92,9 @@ class TestSamples(unittest.TestCase):
             tokens = tokenizer.tokenize(blueprint)
             ast, errors, warnings = parser.parse(tokens)
 
-            self.assert_docs_dont_crash(blueprint, ast)
-            self.assert_completions_dont_crash(blueprint, ast, tokens)
+            if ast is not None:
+                self.assert_docs_dont_crash(blueprint, ast)
+                self.assert_completions_dont_crash(blueprint, ast, tokens)
 
             if errors:
                 raise errors