Make mergeProposalBranch asynchronous

lib/promote_release.js

@@ -151,7 +151,7 @@ class ReleasePromotion {
  const keyPath = await cli.prompt(
  `Please enter the path to your ssh key (Default ${defaultKeyPath}): `,
  { questionType: 'input', defaultAnswer: defaultKeyPath });
- await this.promoteAndSignRelease(keyPath);
+ this.promoteAndSignRelease(keyPath);
 
  cli.separator();
  cli.ok(`Release promotion for ${version} complete.\n`);
@@ -298,12 +298,12 @@ class ReleasePromotion {
  const releaseBranch = `v${versionComponents.major}.x`;
  const proposalBranch = `v${version}-proposal`;
 
- runSync('git', ['checkout', releaseBranch]);
- runSync('git', ['merge', '--ff-only', proposalBranch]);
- runSync('git', ['push', 'upstream', releaseBranch]);
- runSync('git', ['checkout', stagingBranch]);
- runSync('git', ['rebase', releaseBranch]);
- runSync('git', ['push', 'upstream', stagingBranch]);
+ await runAsync('git', ['checkout', releaseBranch]);
+ await runAsync('git', ['merge', '--ff-only', proposalBranch]);
+ await runAsync('git', ['push', 'upstream', releaseBranch]);
+ await runAsync('git', ['checkout', stagingBranch]);
+ await runAsync('git', ['rebase', releaseBranch]);
+ await runAsync('git', ['push', 'upstream', stagingBranch]);
  }
 
  pushReleaseTag() {
@@ -321,7 +321,7 @@ class ReleasePromotion {
  // Since we've committed the Working On commit, the release
  // commit will be 1 removed from tip-of-tree (e.g HEAD~1).
  const releaseCommitSha = this.getCommitSha(1);
- runSync('git', ['checkout', 'master']);
+ runAsync('git', ['checkout', 'master']);
 
  // Pull master from upstream, in case it's not up-to-date.
  runSync('git', ['pull', '--rebase', 'upstream', 'master']);