How to run a code-generator on the top of another code-generator?

Question

Using the source_gen stack to make a code generator, how can I make a generator that generates code that would be the input of another generator (more specifically json_se

Answer 1

Check the build.yaml config file documentation for more info, but I think you should use the applies_builders param that allows to execute another build after the defined one.

The example shows a builder that generates .tar.gz files and then executes another build that takes the .tar.gz files as input

builders:
  # The regular builder config, creates .tar.gz files.
  regular_builder:
    import: "package:my_package/builder.dart"
    builder_factories: ["myBuilder"]
    build_extensions: {".dart": [".tar.gz"]}
    auto_apply: dependents
    apply_builders: [":archive_extract_builder"]
post_process_builders:
  # The post process builder config, extracts .tar.gz files.
  extract_archive_builder:
    import: "package:my_package/extract_archive_builder.dart"
    builder_factory: "myExtractArchiveBuilder"
    input_extensions: [".tar.gz"]

so with source_gen you should implement for your build

applies_builders: ["source_gen|combining_builder", "json_serializable"]

and configure the other builder

json_serializable:
    import: "package:json_serializable/builder.dart"
    builder_factories: ["jsonSerializable"]
    build_extensions: {".dart": ["json_serializable.g.part"]}
    auto_apply: dependents
    build_to: cache
    applies_builders: ["source_gen|combining_builder"]