dart pub publish validation does not respect nested pubspec.yamls

[dcharkes]

Environment

Dart SDK version: 3.1.0-edge.b3cc093e4cafb349008272b594a1693956ff5d41 (be) (Mon Jul 10 12:23:15 2023 +0000) on "macos_arm64"
MacOS: 13.4.1 (22F82)
Normal pub.

Problem

When doing dart pub publish, all code is analyzed with the outermost pubspec.yaml rather than respecting pubspec.yamls in subfolders.

native_assets_builder dacoharkes$ dart pub publish --dry-run
[...]
Validating package... (1.1s)
Package validation found the following potential issues:
* line 5, column 1 of test/data/native_add_add_source/build.dart: This package does not have c_compiler in the `dependencies` or `dev_dependencies` section of `pubspec.yaml`.
    ╷
  5 │ import 'package:c_compiler/c_compiler.dart';
    │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    ╵
[...]

Package has 7 warnings.

pkgs/native_assets_builder/pubspec.yaml.

name: native_assets_builder
description: >-
  This package is the backend that invokes top-level `build.dart` scripts.
version: 0.1.0
repository: https://github.com/dart-lang/native/tree/main/pkgs/native_assets_builder

environment:
  sdk: '>=3.0.0 <4.0.0'

dependencies:
  graphs: ^2.3.1
  logging: ^1.2.0
  native_assets_cli: ^0.1.0
  package_config: ^2.1.0

dev_dependencies:
  dart_flutter_team_lints: ^1.0.0
  test: ^1.24.3
  yaml: ^3.1.2

# no c_compiler.

pkgs/native_assets_builder/test/data/native_add_add_source/pubspec.yaml

name: native_add
description: Sums two numbers with native code.
version: 0.1.0

publish_to: none

environment:
  sdk: '>=3.0.0 <4.0.0'

dependencies:
  c_compiler:
    path: ../../../../c_compiler/ # We have c_compiler here!
  cli_config: ^0.1.1
  logging: ^1.1.1
  native_assets_cli: ^0.1.0

dev_dependencies:
  ffigen: ^8.0.2
  lints: ^2.0.0
  test: ^1.23.1

Expected behavior

The validator being happy.

After having run dart pub get inside pkgs/native_assets_builder/test/data/native_add_add_source/, the dart analyzer is happy. I'd expect dart pub get to be consistent with the analyzer.

Actual behavior

The validator complaining about dependencies missing in the outer pubspec.yaml.