fix(version-dispatch): clear preview comment on every gated early-return

src/version-dispatch.spec.ts

@@ -355,6 +355,63 @@ describe('versionDispatch', () => {
       expect(client.rest.issues.createComment).toHaveBeenCalledTimes(1)
     })
 
+    it('clears stale preview comments when skip-release is added mid-flight', async () => {
+      github.context.payload = {
+        pull_request: {
+          title: 'feat: pending',
+          number: 555,
+          merged: false,
+          state: 'open',
+          user: { login: 'brucewayne' },
+          base: { ref },
+          labels: [{ name: 'skip-release' }],
+        },
+      }
+
+      setupPreviewPaginate(
+        [{ sha: 'aaa1111', commit: { message: 'feat(atoms)!: drop legacy' } }],
+        { aaa1111: [{ filename: 'libraries/atoms/index.ts' }] },
+        [{ id: 9100, body: `${PREVIEW_MARKER}\nstale preview from before the label was added` }]
+      )
+
+      await versionDispatch({ filesystem: fs as never })
+
+      expect(client.rest.issues.deleteComment).toHaveBeenCalledWith({
+        ...repo,
+        comment_id: 9100,
+      })
+      expect(client.rest.issues.createComment).not.toHaveBeenCalled()
+      expect(client.rest.actions.createWorkflowDispatch).not.toHaveBeenCalled()
+    })
+
+    it('clears stale preview comments when the PR base is retargeted off the default branch', async () => {
+      github.context.payload = {
+        pull_request: {
+          title: 'feat: pending',
+          number: 555,
+          merged: false,
+          state: 'open',
+          user: { login: 'brucewayne' },
+          base: { ref: 'wayne-foundation/batmobile-v2' },
+          labels: [],
+        },
+      }
+
+      setupPreviewPaginate(
+        [{ sha: 'aaa1111', commit: { message: 'feat(atoms)!: drop legacy' } }],
+        { aaa1111: [{ filename: 'libraries/atoms/index.ts' }] },
+        [{ id: 9101, body: `${PREVIEW_MARKER}\nstale preview from when base was master` }]
+      )
+
+      await versionDispatch({ filesystem: fs as never })
+
+      expect(client.rest.issues.deleteComment).toHaveBeenCalledWith({
+        ...repo,
+        comment_id: 9101,
+      })
+      expect(client.rest.issues.createComment).not.toHaveBeenCalled()
+    })
+
     it('clears stale comments and posts nothing when no commits bump anything', async () => {
       github.context.payload = {
         pull_request: {

src/version-dispatch.ts

@@ -7,7 +7,7 @@ import { VersionDispatchInput as Input } from './constants'
 import { Filesystem } from './utils/types'
 import { Bump, BUMP_NONE, bumpFromMessage, maxBump } from './version-dispatch/bumps'
 import { filesToPackages } from './version-dispatch/files-to-packages'
-import { postVersionPreview } from './version-dispatch/preview'
+import { clearVersionPreview, postVersionPreview } from './version-dispatch/preview'
 
 type Params = {
   filesystem?: Filesystem
@@ -86,6 +86,7 @@ export async function versionDispatch({ filesystem = fs }: Params = {}) {
   const excludedLabel = (pr.labels ?? []).find((label) => excludedLabels.has(label.name))
   if (excludedLabel) {
     core.notice(`Skipped for excluded label "${excludedLabel.name}"`)
+    if (isPreview) await clearVersionPreview({ client, repo, prNumber: pr.number })
     return null
   }
 
@@ -95,12 +96,14 @@ export async function versionDispatch({ filesystem = fs }: Params = {}) {
 
   if (pr.base?.ref && pr.base.ref !== defaultBranch) {
     core.notice(`Skipped versioning for PR not targeting ${defaultBranch}`)
+    if (isPreview) await clearVersionPreview({ client, repo, prNumber: pr.number })
     return null
   }
 
   const packagePaths = await getPathsByPackageNames({ filesystem })
   if (Object.keys(packagePaths).length === 0) {
     core.warning('No workspace packages discovered. Aborting.')
+    if (isPreview) await clearVersionPreview({ client, repo, prNumber: pr.number })
     return null
   }
 

src/version-dispatch/preview.ts

@@ -123,6 +123,25 @@ export function renderPreviewComment(rows: PreviewRow[]): string {
   return lines.join('\n')
 }
 
+/**
+ * Delete every prior preview comment on the PR. Used by the action's
+ * early-return paths (excluded label, wrong base branch, no workspace
+ * packages, etc.) to make sure a previously-posted preview comment
+ * does not linger after the PR transitions into a gated state.
+ */
+export async function clearVersionPreview({
+  client,
+  repo,
+  prNumber,
+}: {
+  client: GithubClient
+  repo: Repo
+  prNumber: number
+}): Promise<void> {
+  const deleted = await deleteExistingPreviewComments({ client, repo, prNumber })
+  if (deleted > 0) core.info(`preview: cleared ${deleted} stale preview comment(s)`)
+}
+
 async function deleteExistingPreviewComments({
   client,
   repo,