@@ -367,10 +367,19 @@
    source_index = lines.index { |line| line.start_with?("SF:") }
    return unless source_index
    source_path = lines[source_index].delete_prefix("SF:").strip
    source_prefix = source_prefixes.find { |prefix| source_path.start_with?(prefix) }
    source_path = Pathname.new(lines[source_index].delete_prefix("SF:").strip).cleanpath.to_s
    # Homebrew remaps the formula build path to ".". LLVM may then resolve that
    # relative path from CMake's compilation directory at "build/tests".
    relative_source_path = if source_path.start_with?("build/tests/src/")
      source_path.delete_prefix("build/tests/")
    elsif source_path.start_with?("src/")
      source_path
    else
      source_prefix = source_prefixes.find { |prefix| source_path.start_with?(prefix) }
      "src/#{source_path.delete_prefix(source_prefix)}" if source_prefix
    end
    return unless relative_source_path
    return unless source_prefix
    lines[source_index] = "SF:src/#{source_path.delete_prefix(source_prefix)}\n"
    lines[source_index] = "SF:#{relative_source_path}\n"
    "#{lines.join}end_of_record\n"
  end
@@ -476,6 +485,42 @@
        run_test_suite testpath
        generate_coverage_report testpath, ENV.fetch("HOMEBREW_BUILDPATH", "")
      end
      lcov = <<~LCOV
        SF:./src/remapped.cpp
        DA:1,1
        end_of_record
        SF:build/tests/src/remapped_from_compile_dir.cpp
        DA:1,1
        end_of_record
        SF:src/relative.cpp
        DA:1,1
        end_of_record
        SF:#{testpath}/src/absolute.cpp
        DA:1,1
        end_of_record
        SF:./tests/excluded.cpp
        DA:1,1
        end_of_record
        SF:build/tests/tests/excluded_from_compile_dir.cpp
        DA:1,1
        end_of_record
      LCOV
      expected_lcov = <<~LCOV
        SF:src/remapped.cpp
        DA:1,1
        end_of_record
        SF:src/remapped_from_compile_dir.cpp
        DA:1,1
        end_of_record
        SF:src/relative.cpp
        DA:1,1
        end_of_record
        SF:src/absolute.cpp
        DA:1,1
        end_of_record
      LCOV
      assert_equal expected_lcov, lcov_for_source_files(lcov, testpath)
    end
  end
end