feat: add addChangesetUrl placeholder support for custom links

Author: JounQin

.changeset/short-queens-cover.md

@@ -2,4 +2,4 @@
 "changesets-gitlab": minor
 ---
 
-feat: add a new optional `GITLAB_COMMENT_CUSTOM_LINKS` environment variable to override the links content referenced in the cli bot comment
+feat: add a new optional `GITLAB_COMMENT_CUSTOM_LINKS` environment variable to override the links content referenced in the cli bot comment, use `{{ addChangesetUrl }}` placeholder for the dynamic URL to add a changeset

README.md

@@ -54,7 +54,7 @@ GITLAB_CI_USER_NAME                    # optional, username with accessibility t
 GITLAB_CI_USER_EMAIL                   # optional, default `gitlab[bot]@users.noreply.gitlab.com`
 GITLAB_COMMENT_TYPE                    # optional, type of the comment. defaults to `discussion`. can be set to `note` to not create a discussion instead of a thread
 GITLAB_COMMENT_DISCUSSION_AUTO_RESOLVE # optional, automatically resolve added discussion when changeset is present, if you want to always resolve the discussion, you should actually use `GITLAB_COMMENT_TYPE=note` instead, default `true`
-GITLAB_COMMENT_CUSTOM_LINKS            # optional, override the links content referenced in the cli bot comment
+GITLAB_COMMENT_CUSTOM_LINKS            # optional, override the links content referenced in the cli bot comment, use {{ addChangesetUrl }} placeholder for the dynamic URL to add a changeset
 GITLAB_ADD_CHANGESET_MESSAGE           # optional, default commit message for adding changesets on GitLab Web UI
 DEBUG_GITLAB_CREDENTIAL                # optional, whether to log when setting remote url with sensitive `token` displayed
 ```

src/comment.ts

@@ -64,6 +64,10 @@ const getReleasePlanMessage = (releasePlan: ReleasePlan | null) => {
 </details>`
 }
 
+const customLinks = env.GITLAB_COMMENT_CUSTOM_LINKS?.trim()
+
+const ADD_CHANGESET_URL_PLACEHOLDER_REGEXP = /\{\{\s*addChangesetUrl\s*\}\}/
+
 const getAbsentMessage = (
   commitSha: string,
   addChangesetUrl: string,
@@ -77,8 +81,9 @@ Merging this MR will not cause a version bump for any packages. If these changes
 ${getReleasePlanMessage(releasePlan)}
 
 ${
-  env.GITLAB_COMMENT_CUSTOM_LINKS ||
-  `[Click here to learn what changesets are, and how to add one](https://github.com/changesets/changesets/blob/main/docs/adding-a-changeset.md).
+  customLinks
+    ? customLinks.replace(ADD_CHANGESET_URL_PLACEHOLDER_REGEXP, addChangesetUrl)
+    : `[Click here to learn what changesets are, and how to add one](https://github.com/changesets/changesets/blob/main/docs/adding-a-changeset.md).
 
 [Click here if you're a maintainer who wants to add a changeset to this MR](${addChangesetUrl})`
 }
@@ -99,8 +104,9 @@ Latest commit: ${commitSha}
 ${getReleasePlanMessage(releasePlan)}
 
 ${
-  env.GITLAB_COMMENT_CUSTOM_LINKS ||
-  `Not sure what this means? [Click here to learn what changesets are](https://github.com/changesets/changesets/blob/main/docs/adding-a-changeset.md).
+  customLinks
+    ? customLinks.replace(ADD_CHANGESET_URL_PLACEHOLDER_REGEXP, addChangesetUrl)
+    : `Not sure what this means? [Click here to learn what changesets are](https://github.com/changesets/changesets/blob/main/docs/adding-a-changeset.md).
 
 [Click here if you're a maintainer who wants to add another changeset to this MR](${addChangesetUrl})`
 }