Fix: #258 make _get_files treat sourceless commands gracefully

[izashchelkin]

Fixes: #258

[eklitzke]

I've tested this locally and can confirm it fixes #258 for me

[eduardvercaemer]

For anyone lazy that just wants it to work:

bazel_dep(name = "hedron_compile_commands", dev_dependency = True)
git_override(
    module_name = "hedron_compile_commands",
    remote = "https://github.com/eduardvercaemer/bazel-compile-commands-extractor.git",
    commit = "e49f0cd201931f2a3137814a66a0d2e30b45cda1",
)

[jlojosnegros]

Hey @izashchelkin and @eklitzke! 👋

I've tested this fix in production with Envoy proxy (10k+ C++ files) and it works great!

One small suggestion: We could make this more robust by specifically detecting header compilation actions instead of silently skipping ALL sourceless commands.

I'd suggest something like:

if len(source_file_candidates) == 0:
    # Check if this is a known header-only compilation case
    is_header_compile = '-xc++-header' in compile_action.arguments
    if is_header_compile:
        return None  # Expected case: skip header precompilation
    # For unexpected cases, keep assertion for debugging
    assert False, f"No source files found in compile args: {compile_action.arguments}..."

‌

This way:

• ✅ We still fix "No source files found" AssertionError #258, No source files found error #265, No source files found in compile args error #199 (header compilation actions)
• ✅ We preserve error detection for truly unexpected cases
• ✅ Better debugging if new edge cases emerge

Happy to submit this as an additional commit to your PR if you'd like!

Thanks for working on this fix! 🙏