1 files changed, 66 insertions, 0 deletions
diff --git a/src/ref-helper.ts b/src/ref-helper.ts
index f600179..381fa60 100644
--- a/src/ref-helper.ts
+++ b/src/ref-helper.ts
@@ -3,6 +3,8 @@ import {IGitCommandManager} from './git-command-manager'
 import * as core from '@actions/core'
 import * as github from '@actions/github'
 
+export const tagsRefSpec = '+refs/tags/*:refs/tags/*'
+
 export interface ICheckoutInfo {
   ref: string
   startPoint: string
@@ -60,6 +62,16 @@ export async function getCheckoutInfo(
   return result
 }
 
+export function getRefSpecForAllHistory(ref: string, commit: string): string[] {
+  const result = ['+refs/heads/*:refs/remotes/origin/*', tagsRefSpec]
+  if (ref && ref.toUpperCase().startsWith('REFS/PULL/')) {
+    const branch = ref.substring('refs/pull/'.length)
+    result.push(`+${commit || ref}:refs/remotes/pull/${branch}`)
+  }
+
+  return result
+}
+
 export function getRefSpec(ref: string, commit: string): string[] {
   if (!ref && !commit) {
     throw new Error('Args ref and commit cannot both be empty')
@@ -111,6 +123,60 @@ export function getRefSpec(ref: string, commit: string): string[] {
   }
 }
 
+/**
+ * Tests whether the initial fetch created the ref at the expected commit
+ */
+export async function testRef(
+  git: IGitCommandManager,
+  ref: string,
+  commit: string
+): Promise<boolean> {
+  if (!git) {
+    throw new Error('Arg git cannot be empty')
+  }
+
+  if (!ref && !commit) {
+    throw new Error('Args ref and commit cannot both be empty')
+  }
+
+  // No SHA? Nothing to test
+  if (!commit) {
+    return true
+  }
+  // SHA only?
+  else if (!ref) {
+    return await git.shaExists(commit)
+  }
+
+  const upperRef = ref.toUpperCase()
+
+  // refs/heads/
+  if (upperRef.startsWith('REFS/HEADS/')) {
+    const branch = ref.substring('refs/heads/'.length)
+    return (
+      (await git.branchExists(true, `origin/${branch}`)) &&
+      commit === (await git.revParse(`refs/remotes/origin/${branch}`))
+    )
+  }
+  // refs/pull/
+  else if (upperRef.startsWith('REFS/PULL/')) {
+    // Assume matches because fetched using the commit
+    return true
+  }
+  // refs/tags/
+  else if (upperRef.startsWith('REFS/TAGS/')) {
+    const tagName = ref.substring('refs/tags/'.length)
+    return (
+      (await git.tagExists(tagName)) && commit === (await git.revParse(ref))
+    )
+  }
+  // Unexpected
+  else {
+    core.debug(`Unexpected ref format '${ref}' when testing ref info`)
+    return true
+  }
+}
+
 export async function checkCommitInfo(
   token: string,
   commitInfo: string,