Introduce sha action input

Author: lukebettridge

action.yml

@@ -8,6 +8,8 @@ inputs:
   branch:
     description: 'The branch to create'
     default: 'release-candidate'
+  sha:
+    description: 'The SHA1 value for the branch reference'
 runs:
   using: 'node12'
   main: 'dist/index.js'

src/create-branch.ts

@@ -1,7 +1,7 @@
 import { Context } from "@actions/github/lib/context";
 import { GitHub } from "@actions/github";
 
-export async function createBranch(github: any, context: Context, branch: string) {
+export async function createBranch(github: any, context: Context, branch: string, sha?: string) {
   const toolkit : GitHub = new github(githubToken());
     let branchExists;
     // Sometimes branch might come in with refs/heads already
@@ -19,7 +19,7 @@ export async function createBranch(github: any, context: Context, branch: string
       if(error.name === 'HttpError' && error.status === 404) {
         await toolkit.git.createRef({
           ref: `refs/heads/${branch}`,
-          sha: context.sha,
+          sha: sha || context.sha,
           ...context.repo
         })
       } else {

src/main.ts

@@ -5,8 +5,9 @@ import { createBranch } from './create-branch';
 async function run() {
   try {
     const branch = core.getInput('branch');
+    const sha = core.getInput('sha');
     core.debug(`Creating branch ${branch}`);
-    await createBranch(GitHub, context, branch)
+    await createBranch(GitHub, context, branch, sha)
   } catch (error) {
     core.setFailed(error.message);
   }