build: use shared circleci dev-infra for common circleci code

This allows us to remove the `rebase-pr.js` script
so that we can maintain this script in a single place.

.circleci/dynamic_config.yml

@@ -11,6 +11,7 @@ version: 2.1
 
 orbs:
   browser-tools: circleci/browser-tools@1.1.3
+  devinfra: angular/dev-infra@1.0.1
 
 parameters:
   snapshot_changed:
@@ -102,19 +103,18 @@ commands:
 
   rebase_pr:
     steps:
-      - run:
-          name: Rebase PR on target branch
-          shell: bash
-          command: >
-            if [[ -n "${CIRCLE_PR_NUMBER}" ]]; then
-              # User is required for rebase.
-              git config user.name "angular-ci"
-              git config user.email "angular-ci"
-              # Rebase PR on top of target branch.
-              node tools/rebase-pr.js angular/angular-cli ${CIRCLE_PR_NUMBER}
-            else
-              echo "This build is not over a PR, nothing to do."
-            fi
+      - devinfra/rebase-pr-on-target-branch:
+          base_revision: << pipeline.git.base_revision >>
+          head_revision: << pipeline.git.revision >>
+
+  rebase_pr_win:
+    steps:
+      - devinfra/rebase-pr-on-target-branch:
+          base_revision: << pipeline.git.base_revision >>
+          head_revision: << pipeline.git.revision >>
+          # Use `bash.exe` as Shell because the CircleCI-orb command is an
+          # included Bash script and expects Bash as shell.
+          shell: bash.exe
 
   custom_attach_workspace:
     description: Attach workspace at a predefined location
@@ -367,7 +367,7 @@ jobs:
     parallelism: 16
     steps:
       - checkout
-      - rebase_pr
+      - rebase_pr_win
       - setup_windows
       - restore_cache:
           keys:

tools/rebase-pr.js

@@ -1,95 +0,0 @@
-/**
- * @license
- * Copyright Google LLC All Rights Reserved.
- *
- * Use of this source code is governed by an MIT-style license that can be
- * found in the LICENSE file at https://angular.io/license
- */
-// tslint:disable:no-console
-// ** IMPORTANT **
-// This script cannot use external dependencies because it needs to run before they are installed.
-
-const util = require('util');
-const https = require('https');
-const child_process = require('child_process');
-const exec = util.promisify(child_process.exec);
-
-function determineTargetBranch(repository, prNumber) {
-  const pullsUrl = `https://api.github.com/repos/${repository}/pulls/${prNumber}`;
-  // GitHub requires a user agent: https://developer.github.com/v3/#user-agent-required
-  const options = { headers: { 'User-Agent': repository } };
-
-  return new Promise((resolve, reject) => {
-    https
-      .get(pullsUrl, options, (res) => {
-        const { statusCode } = res;
-        const contentType = res.headers['content-type'];
-
-        let error;
-        if (statusCode !== 200) {
-          error = new Error(`Request Failed.\nStatus Code: ${statusCode}.\nResponse: ${res}.\n' +`);
-        } else if (!/^application\/json/.test(contentType)) {
-          error = new Error(
-            'Invalid content-type.\n' + `Expected application/json but received ${contentType}`,
-          );
-        }
-        if (error) {
-          reject(error);
-          res.resume();
-          return;
-        }
-
-        res.setEncoding('utf8');
-        let rawData = '';
-        res.on('data', (chunk) => {
-          rawData += chunk;
-        });
-        res.on('end', () => {
-          try {
-            const parsedData = JSON.parse(rawData);
-            resolve(parsedData['base']['ref']);
-          } catch (e) {
-            reject(e);
-          }
-        });
-      })
-      .on('error', (e) => {
-        reject(e);
-      });
-  });
-}
-
-if (process.argv.length != 4) {
-  console.error(`This script requires the GitHub repository and PR number as arguments.`);
-  console.error(`Example: node scripts/rebase-pr.js angular/angular 123`);
-  process.exitCode = 1;
-  return;
-}
-
-const repository = process.argv[2];
-const prNumber = process.argv[3];
-let targetBranch;
-
-return Promise.resolve()
-  .then(() => {
-    console.log(`Determining target branch for PR ${prNumber} on ${repository}.`);
-    return determineTargetBranch(repository, prNumber);
-  })
-  .then((target) => {
-    targetBranch = target;
-    console.log(`Target branch is ${targetBranch}.`);
-  })
-  .then(() => {
-    console.log(`Fetching ${targetBranch} from origin.`);
-    return exec(`git fetch origin ${targetBranch}`);
-  })
-  .then((target) => {
-    console.log(`Rebasing current branch on ${targetBranch}.`);
-    return exec(`git rebase origin/${targetBranch}`);
-  })
-  .then(() => console.log('Rebase successfull.'))
-  .catch((err) => {
-    console.log('Failed to rebase on top or target branch.\n');
-    console.error(err);
-    process.exitCode = 1;
-  });