Merge pull request #197 from crazy-max/rm-baseref-def-branch

remove support of default branch global exp for push tag events

Author: crazy-max

README.md

@@ -675,20 +675,26 @@ Returns the short commit SHA that triggered the workflow run (e.g., `90dd603`).
 Returns the base ref or target branch of the pull request that triggered the
 workflow run. Will be empty for a branch reference:
 
-| Event           | Ref                           | Output             |
-|-----------------|-------------------------------|--------------------|
-| `pull_request`  | `refs/pull/2/merge`           | `master`           |
-| `push`          | `refs/heads/master`           |                    |
-| `push`          | `refs/heads/my/branch`        |                    |
-| `push tag`      | `refs/tags/v1.2.3`            | `master`           |
+| Event          | Ref                           | Output             |
+|----------------|-------------------------------|--------------------|
+| `pull_request` | `refs/pull/2/merge`           | `master`           |
+| `push`         | `refs/heads/master`           |                    |
+| `push`         | `refs/heads/my/branch`        |                    |
+| `push tag`*    | `refs/tags/v1.2.3`            | `master`           |
+
+> *`base_ref` is available in the push payload but doesn't always seem to 
+> return the expected branch when the push tag event occurs. It's also
+> [not documented in GitHub docs](https://docs.github.com/en/developers/webhooks-and-events/webhooks/webhook-events-and-payloads#push).
+> We keep it for backward compatibility, but it's **not recommended relying on it**.
+> More context in [#192](https://github.com/docker/metadata-action/pull/192#discussion_r854673012). 
 
 #### `{{is_default_branch}}`
 
 Returns `true` if the branch that triggered the workflow run is the default
 one, otherwise `false`.
 
 Will compare against the branch name that triggered the workflow run or the 
-base ref or target branch for a pull request or a tag.
+base ref for a pull request.
 
 #### `{{date '<format>'}}`
 

__tests__/meta.test.ts

@@ -1332,18 +1332,15 @@ describe('tag', () => {
       {
         main: 'v1.1.1-860c190-foo',
         partial: [
-          'master-foo',
-          'defbranch-foo'
+          'master-foo'
         ],
         latest: false
       } as Version,
       [
         'org/app:v1.1.1-860c190-foo',
         'org/app:master-foo',
-        'org/app:defbranch-foo',
         'ghcr.io/user/app:v1.1.1-860c190-foo',
-        'ghcr.io/user/app:master-foo',
-        'ghcr.io/user/app:defbranch-foo'
+        'ghcr.io/user/app:master-foo'
       ],
       [
         "org.opencontainers.image.title=Hello-World",

dist/index.js

@@ -369,16 +369,22 @@ export class Meta {
         if (/^refs\/tags\//.test(ctx.ref) && ctx.payload?.base_ref != undefined) {
           return ctx.payload.base_ref.replace(/^refs\/heads\//g, '').replace(/\//g, '-');
         }
+        // FIXME: keep this for backward compatibility even if doesn't always seem
+        //  to return the expected branch. See the comment below.
         if (/^refs\/pull\//.test(ctx.ref) && ctx.payload?.pull_request?.base?.ref != undefined) {
           return ctx.payload.pull_request.base.ref;
         }
         return '';
       },
       is_default_branch: function () {
         let branch = ctx.ref.replace(/^refs\/heads\//g, '');
-        if (/^refs\/tags\//.test(ctx.ref) && ctx.payload?.base_ref != undefined) {
-          branch = ctx.payload.base_ref.replace(/^refs\/heads\//g, '');
-        }
+        // TODO: "base_ref" is available in the push payload but doesn't always seem to
+        //  return the expected branch when the push tag event occurs. It's also not
+        //  documented in GitHub docs: https://docs.github.com/en/developers/webhooks-and-events/webhooks/webhook-events-and-payloads#push
+        //  more context: https://github.com/docker/metadata-action/pull/192#discussion_r854673012
+        // if (/^refs\/tags\//.test(ctx.ref) && ctx.payload?.base_ref != undefined) {
+        //   branch = ctx.payload.base_ref.replace(/^refs\/heads\//g, '');
+        // }
         if (/^refs\/pull\//.test(ctx.ref) && ctx.payload?.pull_request?.base?.ref != undefined) {
           branch = ctx.payload.pull_request.base.ref;
         }