Add options.last_files_match_only to simulate CODEOWNERS (#80)

* Add options.last_match_only to simulate CODEOWNERS

* Add a test case for the last_match_only option

* Update dist

* Rename last_match_only to last_files_match_only

Co-authored-by: necojackarc <[email protected]>

Author: k0kubun

README.md

@@ -175,6 +175,10 @@ options:
   # Randomly pick reviewers up to this number.
   # Do not set this option if you'd like to assign all matching reviewers.
   number_of_reviewers: 3
+
+  # If it's true, the last matching files-change pattern takes the most precedence (CODEOWNERS-compatible)
+  # See https://github.com/necojackarc/auto-request-review/pull/80 for more details.
+  last_files_match_only: false
 ```
 
 The default configuration file location is `.github/auto_request_review.yml` but you can override it in your workflow configuration file.

dist/index.js

@@ -34,6 +34,15 @@ function fetch_other_group_members({ author, config }) {
 }
 
 function identify_reviewers_by_changed_files({ config, changed_files, excludes = [] }) {
+  const DEFAULT_OPTIONS = {
+    last_files_match_only: false,
+  };
+
+  const { last_files_match_only } = {
+    ...DEFAULT_OPTIONS,
+    ...config.options,
+  };
+
   if (!config.files) {
     core.info('A "files" key does not exist in config; returning no reviewers for changed files.');
     return [];
@@ -43,6 +52,9 @@ function identify_reviewers_by_changed_files({ config, changed_files, excludes =
 
   Object.entries(config.files).forEach(([ glob_pattern, reviewers ]) => {
     if (changed_files.some((changed_file) => minimatch(changed_file, glob_pattern))) {
+      if (last_files_match_only) {
+        matching_reviewers.length = 0; // clear previous matches
+      }
       matching_reviewers.push(...reviewers);
     }
   });

src/reviewer.js

@@ -80,6 +80,7 @@ describe('reviewer', function() {
       files: {
         '**/super-star': [ 'mario', 'luigi' ],
         'backend/**/*': [ 'backend-engineers' ],
+        'backend/**/some-specific-file': [ 'mario', 'someone-specific' ],
         'frontend/**/*': [ 'frontend-engineers', 'toad' ],
       },
     };
@@ -114,6 +115,17 @@ describe('reviewer', function() {
       const excludes = [ 'wario', 'waluigi' ];
       expect(identify_reviewers_by_changed_files({ config, changed_files, excludes })).to.have.members([ 'mario', 'luigi', 'princess-peach', 'toad' ]);
     });
+
+    it('uses the only last matching files-changed pattern with `last_files_match_only` `true` (CODEWONERS-compatible)', function() {
+      const changed_files = [ 'backend/some-specific-file' ];
+      const config_with_last_files_match_only = {
+        ...config,
+        options: {
+          last_files_match_only: true,
+        },
+      };
+      expect(identify_reviewers_by_changed_files({ config: config_with_last_files_match_only, changed_files })).to.have.members([ 'mario', 'someone-specific' ]);
+    });
   });
 
   describe('identify_reviewers_by_author()', function() {