Dart Parser: Intentional Differences and Improvements

July 18, 2026 · View on GitHub

Summary

The Dart parser in Provenant preserves pubspec and pubspec.lock metadata more accurately than the Python reference implementation in several concrete ways:

  1. dependency scope is mapped explicitly (dependencies, dev_dependencies, dependency_overrides, environment)
  2. YAML trailing newlines in descriptions are preserved
  3. lockfile entries distinguish direct main, direct dev, and graph-derived transitive runtime vs dev-only dependencies
  4. manifest and lockfile dependency source descriptors are preserved for hosted / git / path / sdk forms
  5. publish_to: none, legacy top-level lockfile sdk:, and additional pubspec metadata fields are surfaced explicitly

Improvements

1. Dependency scope correction

Rust preserves explicit dependency scopes from pubspec.yaml instead of leaving them null. Runtime dependencies stay under dependencies; development-only ones stay under dev_dependencies; environment constraints stay under environment.

2. YAML description fidelity

Rust preserves trailing newlines from folded/literal YAML description blocks, which keeps the original semantic formatting intact.

3. Lockfile direct/dev/transitive semantics

Rust now keeps pub lockfile intent more truthfully instead of flattening every entry into a direct runtime dependency:

  • direct main → is_direct=true, is_runtime=true
  • direct dev → is_direct=true, is_runtime=false, is_optional=true
  • transitive packages are classified by graph reachability from direct main vs direct dev roots
  • legacy top-level sdk: is accepted alongside modern sdks:

This means dev-only transitives are no longer overstated as runtime dependencies just because they appear in the lockfile.

4. Dependency source descriptor preservation

Rust now keeps richer dependency-source detail for pubspec manifests and lockfiles:

  • manifest dependency maps preserve hosted / git / path / sdk descriptors in dependency extra_data
  • lockfile package entries preserve source, description, and dependency-kind metadata in both dependency and resolved-package extra_data
  • path lockfile entries such as { path: "../pkg", relative: true } no longer disappear into a generic version-only view

5. Pub metadata parity

Rust now also surfaces several package-level pubspec metadata fields more truthfully:

  • publish_to: none marks the package as private
  • archive_url is honored as download_url
  • platforms, funding, topics, screenshots, false_secrets, and ignored_advisories are preserved in extra_data
  • topics also populate keywords

6. Pub workspace topology

  • Root pubspec.yaml workspace: member paths are preserved in extra_data.workspace_members.
  • Assembly claims those member directories for Dart workspace topology, keeps each member as its own package, and attributes a shared root pubspec.lock honestly to members that declare matching direct deps (otherwise hoisted).

Coverage

Coverage includes:

  • explicit dependency scope extraction
  • YAML newline preservation
  • lockfile direct/dev/transitive classification
  • hosted / git / path / sdk descriptor preservation
  • legacy sdk: lockfile compatibility
  • publish_to: none and archive_url behavior
  • pub workspace member extraction and topology assembly
  • parser-only goldens for publish metadata, dict-style dependency descriptors, and path lockfiles