[janedbal]

A .cov file lists every file in the coverage scope. A file without executable lines gets an empty line list:

Consts.php => []           // class with only constants
Iface.php  => []           // interface
Status.php => []           // enum without methods
Multi.php  => {"9":[],…,"21":[1]}

Clover and Cobertura inputs leave such files out, because the extractors skip entries without lines. With .cov input, the empty entries break check:

• check --verbose throws DivisionByZeroError. It prints the coverage percentage of each file, and FileCoverage::getCoveragePercentage() divides by the number of executable lines. Without --verbose, nothing calls this method.

  Info: Checking files listed in coverage report
  ‼️  Internal error: DivisionByZeroError: Division by zero
   at src/Coverage/FileCoverage.php:30
  

• An empty (0-byte) PHP file throws ValueError, also without --verbose. range(1, 0) returns two line numbers for zero lines, so array_combine() in CoverageGuard gets arrays of different sizes.

Now CoverageProvider skips entries without executable lines, for every input format. It skips them after the integrity checks, so a missing file is still reported. Such a file has nothing to cover, so no rule can report it. The "analysed N files" count is now the same for all formats: the same PHPUnit run gave 2 files for Clover and 5 files for .cov.

• New test with an interface and an empty file in a .cov file, with and without --verbose. On master, it throws DivisionByZeroError and ValueError.
• The test creates ProcessedCodeCoverageData, so tests/CoverageGuardTest.php joins the existing PHPStan ignore for internal php-code-coverage classes.

Co-Authored-By: Claude Code