[tools] Remove node backport script and leave a readme

There is a better maintained script in node-code-utils which properly
bumps the version numbers for each of the LTS branches, which is more
useful. Node collaborators also use this script, so it will make
backports more uniform.

Change-Id: If5449b8a801c4bd14f39d59b7af52cc959989be7
Reviewed-on: https://chromium-review.googlesource.com/c/1328927Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57393}

tools/node/README.md

+# Node.js Backports
+
+We no longer maintain our own backport script.
+
+For backporting V8 changes to Node.js, there is a useful script in
+[node-core-utils][1]. You can use the `git node v8 backport` command, which will
+bump the necessary V8 version numbers depending on the specific branch.
+
+See the [Node.js documentation][2] on V8 backports for a guide.
+
+[1]: https://github.com/nodejs/node-core-utils
+[2]: https://github.com/nodejs/node/blob/master/doc/guides/maintaining-V8.md

tools/node/backport_node.py

-#!/usr/bin/env python
-# Copyright 2017 the V8 project authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-"""
-Use this script to cherry-pick a V8 commit to backport to a Node.js checkout.
-
-Requirements:
-  - Node.js checkout to backport to.
-  - V8 checkout that contains the commit to cherry-pick.
-
-Usage:
-  $ backport_node.py <path_to_v8> <path_to_node> <commit-hash>
-
-  This will apply the commit to <path_to_node>/deps/v8 and create a commit in
-  the Node.js checkout, increment patch level, and copy over the original
-  commit message.
-
-Optional flags:
-  --no-review  Run `gclient sync` on the V8 checkout before updating.
-"""
-
-import argparse
-import os
-import subprocess
-import re
-import sys
-
-TARGET_SUBDIR = os.path.join("deps", "v8")
-VERSION_FILE = os.path.join("include", "v8-version.h")
-VERSION_PATTERN = r'(?<=#define V8_PATCH_LEVEL )\d+'
-
-def FileToText(file_name):
-  with open(file_name) as f:
-    return f.read()
-
-def TextToFile(text, file_name):
-  with open(file_name, "w") as f:
-    f.write(text)
-
-
-def Clean(options):
-  print ">> Cleaning target directory."
-  subprocess.check_call(["git", "clean", "-fd"],
-                        cwd = os.path.join(options.node_path, TARGET_SUBDIR))
-
-def CherryPick(options):
-  print ">> Apply patch."
-  patch = subprocess.Popen(["git", "diff-tree", "-p", options.commit],
-                           stdout=subprocess.PIPE, cwd=options.v8_path)
-  patch.wait()
-  try:
-    subprocess.check_output(["git", "apply", "-3", "--directory=%s" % TARGET_SUBDIR],
-                            stdin=patch.stdout, cwd=options.node_path)
-  except:
-    print ">> In another shell, please resolve patch conflicts"
-    print ">> and `git add` affected files."
-    print ">> Finally continue by entering RESOLVED."
-    while raw_input("[RESOLVED]") != "RESOLVED":
-      print ">> You need to type RESOLVED"
-
-def UpdateVersion(options):
-  print ">> Increment patch level."
-  version_file = os.path.join(options.node_path, TARGET_SUBDIR, VERSION_FILE)
-  text = FileToText(version_file)
-  def increment(match):
-    patch = int(match.group(0))
-    return str(patch + 1)
-  text = re.sub(VERSION_PATTERN, increment, text, flags=re.MULTILINE)
-  TextToFile(text, version_file)
-
-def CreateCommit(options):
-  print ">> Creating commit."
-  # Find short hash from source.
-  shorthash = subprocess.check_output(
-      ["git", "rev-parse", "--short", options.commit],
-      cwd=options.v8_path).strip()
-
-  # Commit message
-  title = "deps: backport %s from upstream V8"  % shorthash
-  body = subprocess.check_output(
-      ["git", "log", options.commit, "-1", "--format=%B"],
-      cwd=options.v8_path).strip()
-  body = '\n'.join("  " + line for line in body.splitlines())
-
-  message = title + "\n\nOriginal commit message:\n\n" + body
-
-  # Create commit at target.
-  review_message = "--no-edit" if options.no_review else "--edit"
-  git_commands = [
-    ["git", "checkout", "-b", "backport_%s" % shorthash],  # new branch
-    ["git", "add", TARGET_SUBDIR],                         # add files
-    ["git", "commit", "-m", message, review_message]       # new commit
-  ]
-  for command in git_commands:
-    subprocess.check_call(command, cwd=options.node_path)
-
-def ParseOptions(args):
-  parser = argparse.ArgumentParser(description="Backport V8 commit to Node.js")
-  parser.add_argument("v8_path", help="Path to V8 checkout")
-  parser.add_argument("node_path", help="Path to Node.js checkout")
-  parser.add_argument("commit", help="Commit to backport")
-  parser.add_argument("--no-review", action="store_true",
-                      help="Skip editing commit message")
-  options = parser.parse_args(args)
-  options.v8_path = os.path.abspath(options.v8_path)
-  assert os.path.isdir(options.v8_path)
-  options.node_path = os.path.abspath(options.node_path)
-  assert os.path.isdir(options.node_path)
-  return options
-
-def Main(args):
-  options = ParseOptions(args)
-  Clean(options)
-  try:
-    CherryPick(options)
-    UpdateVersion(options)
-    CreateCommit(options)
-  except:
-    print ">> Failed. Resetting."
-    subprocess.check_output(["git", "reset", "--hard"], cwd=options.node_path)
-    raise
-
-if __name__ == "__main__":
-  Main(sys.argv[1:])

tools/node/test_backport_node.py

-#!/usr/bin/env python
-# Copyright 2017 the V8 project authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import os
-import shutil
-import subprocess
-import sys
-import tempfile
-import unittest
-
-import backport_node
-
-# Base paths.
-BASE_DIR = os.path.dirname(os.path.abspath(__file__))
-TEST_DATA = os.path.join(BASE_DIR, 'testdata')
-
-def gitify(path):
-  files = os.listdir(path)
-  subprocess.check_call(['git', 'init'], cwd=path)
-  subprocess.check_call(['git', 'add'] + files, cwd=path)
-  subprocess.check_call(['git', 'commit', '-m', 'Initial'], cwd=path)
-
-class TestUpdateNode(unittest.TestCase):
-  def setUp(self):
-    self.workdir = tempfile.mkdtemp(prefix='tmp_test_node_')
-
-  def tearDown(self):
-    shutil.rmtree(self.workdir)
-
-  def testUpdate(self):
-    v8_cwd = os.path.join(self.workdir, 'v8')
-    node_cwd = os.path.join(self.workdir, 'node')
-
-    # Set up V8 test fixture.
-    shutil.copytree(src=os.path.join(TEST_DATA, 'v8'), dst=v8_cwd)
-    gitify(v8_cwd)
-
-    # Set up node test fixture.
-    shutil.copytree(src=os.path.join(TEST_DATA, 'node'), dst=node_cwd)
-    gitify(os.path.join(node_cwd))
-
-    # Add a patch.
-    with open(os.path.join(v8_cwd, 'v8_foo'), 'w') as f:
-      f.write('zonk')
-    subprocess.check_call(['git', 'add', 'v8_foo'], cwd=v8_cwd)
-    subprocess.check_call(['git', 'commit', '-m', "Title\n\nBody"], cwd=v8_cwd)
-    commit = subprocess.check_output(['git', 'rev-parse', 'HEAD'], cwd=v8_cwd).strip()
-
-    # Run update script.
-    backport_node.Main([v8_cwd, node_cwd, commit, "--no-review"])
-
-    # Check message.
-    message = subprocess.check_output(['git', 'log', '-1', '--format=%B'], cwd=node_cwd)
-    self.assertIn('Original commit message:\n\n  Title\n\n  Body', message)
-
-    # Check patch.
-    gitlog = subprocess.check_output(
-        ['git', 'diff', 'master', '--cached', '--', 'deps/v8/v8_foo'],
-        cwd=node_cwd,
-    )
-    self.assertIn('+zonk', gitlog.strip())
-
-    # Check version.
-    version_file = os.path.join(node_cwd, "deps", "v8", "include", "v8-version.h")
-    self.assertIn('#define V8_PATCH_LEVEL 4322', backport_node.FileToText(version_file))
-
-if __name__ == "__main__":
-  unittest.main()