Fix ModuleThreadContext to only ignore dev dependencies when applicable

[namanONcode]

Closes #21596

Description

This pull request improves the handling of development-only dependencies (dev_dependency) in Bazel's Bzlmod module system. Specifically, it ensures that any module overrides for dev-only dependencies are ignored when the --ignore_dev_dependency flag is set. The changes introduce a mechanism to track ignored dev dependencies and filter out their overrides.

Key changes:

• Core logic improvements:

  • Added a Set<String> ignoredDevDeps to ModuleThreadContext to track module names of dev-only dependencies that are ignored when --ignore_dev_dependency is enabled.
  • Modified the buildOverrides method to remove any overrides for modules listed in ignoredDevDeps, ensuring that overrides for ignored dev dependencies do not affect the build.
  • Updated the bazelDep logic to call addIgnoredDevDep when a dev dependency is ignored, ensuring the ignored modules are properly tracked.

• Testing improvements:

  • Enhanced and added new tests in ModuleFileFunctionTest to verify that overrides for dev-only dependencies are filtered out when --ignore_dev_dependency is set, and that overrides for regular dependencies are preserved.

Motivation

Fixes #21596

Previously, ModuleThreadContext.addOverride() had a blanket if (shouldIgnoreDevDeps()) return; that discarded all overrides when --ignore_dev_dependency was set, regardless of whether the overridden module was actually a dev dependency. This PR fixes this bug so that only the dev dependency overrides are safely ignored.

Build API Changes

No

Checklist

• I have added tests for the new use cases (if any).
• I have updated the documentation (if applicable).

Release Notes

RELNOTES: None

[Copilot]

Pull request overview

This PR refines Bzlmod’s handling of --ignore_dev_dependency by ensuring module overrides are only ignored for dev dependencies that are actually ignored, instead of dropping all overrides when the flag is set.

Changes:

• Track ignored dev-dependency module names during bazel_dep(..., dev_dependency=True) when --ignore_dev_dependency is enabled.
• Filter overrides for those ignored dev dependencies when constructing the root module’s override map.
• Expand ModuleFileFunctionTest coverage to assert dev-only overrides are filtered while non-dev overrides remain.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/main/java/com/google/devtools/build/lib/bazel/bzlmod/ModuleThreadContext.java	Adds tracking of ignored dev deps and filters override output accordingly.
src/main/java/com/google/devtools/build/lib/bazel/bzlmod/ModuleFileGlobals.java	Records ignored dev deps when bazel_dep is skipped due to --ignore_dev_dependency.
src/test/java/com/google/devtools/build/lib/bazel/bzlmod/ModuleFileFunctionTest.java	Adds/adjusts tests asserting override filtering behavior with --ignore_dev_dependency.

Comments suppressed due to low confidence (1)

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/ModuleThreadContext.java:363

• addOverride() no longer ignores override directives in non-root modules. The Starlark docs for override directives state they only take effect in the root module; with this change, non-root module evaluation can now fail (e.g., duplicate overrides now throw) despite the overrides being semantically ignored. Consider short-circuiting here when the current module key is not ModuleKey.ROOT, and keep the dev-dep filtering logic separate (only applied for the root module when --ignore_dev_dependency is set).

  public void addOverride(String moduleName, ModuleOverride override) throws EvalException {
    ModuleOverride existingOverride = overrides.putIfAbsent(moduleName, override);
    if (existingOverride != null) {
      throw Starlark.errorf("multiple overrides for dep %s found", moduleName);
    }
  }

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[meteorcloudy]

Can you update the PR description according to our template?

[namanONcode]

Can you update the PR description according to our template?

I Fixed and implemented all suggestion give a look

[Wyverald]

I actually think the fix should be much simpler: if --ignore_dev_dependencies is set, all overrides should be ignored. A dev dependency is simply a dependency edge that is ignored if the current module is not the root module. So --ignore_dev_dependencies effectively pretends the current (root) module is non-root. But overrides don't take effective when they're in non-root modules anyway.