[FR]: Change exit code when linting requested but no lintable targets provided

[scasagrande]

What is the current behavior?

When running aspect lint and providing an explicit list of targets, the process will exit with 1 if no lint-able targets were specified.

Describe the feature

The request here is to change the exit code to 4, matching the behaviour of bazel test when testing is requested but no test targets are specified.

Original slack thread: https://bazelbuild.slack.com/archives/C04281DTLH0/p1784137418806149

[thesayyn]

This looks like a small, contained fix. The exit code for this case is hardcoded in crates/aspect-cli/src/builtins/aspect/lint.axl, in the _impl function's exit-code block (~line 1078-1104):

elif not lint_tools_run:
    if rc.flag_values("--aspects", command = "build"):
        error(ctx.std, (
            "Lint aspect(s) configured but produced no rules_lint output. " +
            "Verify the configured aspect is from aspect_rules_lint and " +
            "that your target pattern includes lintable targets."
        ))
    else:
        error(ctx.std, (
            "No lint aspect configured. Pass --aspect=<label> " +
            "(e.g. --aspect=//tools/lint:linters.bzl%shellcheck) or add " +
            "--aspects=… via a bazelrc --config."
        ))
    exit_code = 1

aspect-cli already defines Bazel's exit code constants, including NO_TESTS_FOUND = 4, in crates/aspect-cli/src/builtins/aspect/bazel.axl (exit_codes struct). aspect test gets its exit 4 "for free" by passing through the real bazel test subprocess exit code, but lint.axl computes its own exit code, so it needs to set this explicitly.

Suggested fix — only the "aspects configured but produced no output for these targets" branch matches the issue (the "no aspect configured at all" branch is a distinct config error and should probably keep exit code 1):

load("@aspect//bazel.axl", "BazelTrait", "exit_codes")
...
    elif not lint_tools_run:
        if rc.flag_values("--aspects", command = "build"):
            error(ctx.std, (
                "Lint aspect(s) configured but produced no rules_lint output. " +
                "Verify the configured aspect is from aspect_rules_lint and " +
                "that your target pattern includes lintable targets."
            ))
            exit_code = exit_codes.NO_TESTS_FOUND
        else:
            error(ctx.std, (
                "No lint aspect configured. Pass --aspect=<label> " +
                "(e.g. --aspect=//tools/lint:linters.bzl%shellcheck) or add " +
                "--aspects=… via a bazelrc --config."
            ))
            exit_code = 1

I checked lint_results_test.axl, lint_comments_test.axl, and gitlab_lint_comments_test.axl — none assert exit_code == 1 for this path, so this shouldn't break existing tests, though a new test case for the exit-4 branch would be a good addition.

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Generated by Claude Code

[scasagrande]

Yep that's pretty much what I deduced