Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

[7.2.0] Let Label#debugPrint emit label strings in display form #22460

Merged
merged 1 commit into from
May 21, 2024
Merged

[7.2.0] Let Label#debugPrint emit label strings in display form #22460

merged 1 commit into from
May 21, 2024

Commits on May 21, 2024

  1. Let Label#debugPrint emit label strings in display form 

    This is a reland of 30b95e3 with a different approach to emitting display form labels that avoids adding a new `to_display_form()` method to `Label`:
* In action command lines, which are the most frequent use of labels in rule implementation functions, labels are automatically emitted in display form since 9d3a8b0.
* In module extensions and repository rules, if labels can be turned into display form, the inverse of the repository mapping would need to be tracked in lockfiles and marker files for correct incrementality. Furthermore, allowing implementation functions to access apparent names would allow them to "discriminate" against them, thus possibly breaking the user's capability to map repos at will via `use_repo` and `repo_name`. Similar to how providers on a target can't be enumerated, it is thus safer to not provide this information to the implementation functions directly.

This change thus implements `StarlarkValue#debugPrint` for `Label` to allow ruleset authors to emit labels in display form in warnings and error messages while ensuring that Starlark logic doesn't have access to this information. `print("My message", label)` degrades gracefully with older Bazel versions (it just prints a canonical label literal) and can thus be adopted immediately without a need for feature detection.

This requires changing the signature of `StarlarkValue#debugPrint` to receive the `StarlarkThread` instead of just the `StarlarkSemantics`. Since `debugPrint` is meant for emitting potentially non-deterministic information, it is safe to give it access to `StarlarkThread`.

Also improves the Bzlmod cycle reporter so that it prints helpful information on a cycle encountered in a previous iteration of this PR.

Fixes bazelbuild#20486

RELNOTES: `Label` instances passed to `print` or `fail` as positional arguments are now formatted with apparent repository names (optimized for human readability).

Closes bazelbuild#21963.

PiperOrigin-RevId: 635589078
Change-Id: If60fdc632a59f19dad0cb02312690c15a0540c8e
    @fmeum
    fmeum committed May 21, 2024
    Configuration menu
    Copy the full SHA
    e8eb194 View commit details
    Browse the repository at this point in the history