Pub Package Explorer

Use this workflow to read source code for a dependency package in a Dart or Flutter project.

Resolve a Package Source Path

1. Confirm the project contains .dart_tool/package_config.json.
2. Read the package entry from packages[] by name.
3. Extract:

• rootUri (package root, usually in pub cache)
• packageUri (usually lib/)

4. Build source path as rootUri + packageUri.
5. Convert file:// URI to a filesystem path before reading files.

Use this command pattern:

PACKAGE="analyzer"
CONFIG=".dart_tool/package_config.json"

SOURCE_URI="$(jq -r --arg pkg "$PACKAGE" '
  .packages[]
  | select(.name == $pkg)
  | (.rootUri + (if (.rootUri | endswith("/")) then "" else "/" end) + .packageUri)
' "$CONFIG")"

Convert the URI to a local path:

SOURCE_PATH="$(printf '%s\n' "$SOURCE_URI" | sed 's#^file://##')"

Then inspect source files under that directory (rg, ls, cat).

Useful Variants

• Return only the package root:

jq -r --arg pkg "$PACKAGE" '
  .packages[]
  | select(.name == $pkg)
  | .rootUri
' .dart_tool/package_config.json

• Return both root and package URI:

jq -r --arg pkg "$PACKAGE" '
  .packages[]
  | select(.name == $pkg)
  | "\(.rootUri)\t\(.packageUri)"
' .dart_tool/package_config.json

Verification and Error Handling

• If no package matches, stop and report that the package is not in package_config.json.
• If .dart_tool/package_config.json is missing, run dependency resolution first (dart pub get or flutter pub get) and retry.
• Prefer reading from rootUri + packageUri because package APIs are exposed from that subpath, not always from the package root.