Added primitive support for COVERAGE_PATH_EQUIVALENCE.

Author: grigorye

lib/slather/coverage_info.rb

@@ -71,7 +71,11 @@ def rate_branches_tested
     end
 
     def source_file_pathname_relative_to_repo_root
-      source_file_pathname.realpath.relative_path_from(Pathname("./").realpath)
+      test_path=source_file_pathname
+      if ENV["COVERAGE_PATH_EQUIVALENCE"]
+        test_path=Pathname("." + "#{source_file_pathname}".delete_prefix(ENV["COVERAGE_PATH_EQUIVALENCE"].delete_suffix(",.")))
+      end
+      test_path.realpath.relative_path_from(Pathname("./").realpath)
     end
 
     def ignored?

lib/slather/project.rb

@@ -269,6 +269,9 @@ def unsafe_llvm_cov_export_output(binary_path)
       if self.arch
         llvm_cov_args << "--arch" << self.arch
       end
+      if ENV["COVERAGE_PATH_EQUIVALENCE"]
+        llvm_cov_args << "-path-equivalence=#{ENV["COVERAGE_PATH_EQUIVALENCE"]}"
+      end
       `xcrun llvm-cov #{llvm_cov_args.shelljoin}`
     end
     private :unsafe_llvm_cov_export_output
@@ -293,6 +296,9 @@ def unsafe_profdata_llvm_cov_output(binary_path, source_files)
       if self.arch
         llvm_cov_args << "--arch" << self.arch
       end
+      if ENV["COVERAGE_PATH_EQUIVALENCE"]
+        llvm_cov_args << "-path-equivalence=#{ENV["COVERAGE_PATH_EQUIVALENCE"]}"
+      end
 
       # POSIX systems have an ARG_MAX for the maximum total length of the command line, so the command may fail with an error message of "Argument list too long".
       # Using the xargs command we can break the list of source_files into sublists small enough to be acceptable.