Each .dart file under this path creates a test case in pkgs/_analyzer_macros/test/golden_test.dart and pkgs/_cfe_macros/test/golden_test.dart.
The test case looks for golden files next to the .dart file and asserts that they match.
To test introspection, add .analyzer.json and/or .cfe.json golden files. The JSON in the golden file is compared with the query output on the .dart file, which must be tagged with the QueryClass macro.
To test macro application, add .analyzer.augmentations and/or .cfe.augmentations golden files. These are compared with the full macro augmentation output of the corresponding .dart file.