(don't merge) Add --abort/--continue option to cherry_picker.py

cherry_picker/cherry_picker.py

@@ -1,59 +1,144 @@
+#!/usr/bin/env python3
+#  -*- coding: utf-8 -*-
+
 import click
 import os
 import subprocess
 import webbrowser
 
 
 @click.command()
-@click.option('--dry-run', is_flag=True)
+@click.option('--dry-run', is_flag=True,
+              help="Prints out the commands, but not executed.")
 @click.option('--push', 'pr_remote', metavar='REMOTE',
               help='git remote to use for PR branches', default='origin')
-@click.argument('commit_sha1', 'The commit sha1 to be cherry-picked')
+@click.option('--abort', 'abort', flag_value=True, default=None,
+              help="Abort current cherry-pick and clean up branch")
+@click.option('--continue', 'abort', flag_value=False, default=None,
+              help="Continue cherry-pick, push, and clean up branch")
+@click.argument('commit_sha1', 'The commit sha1 to be cherry-picked', nargs=1,
+                default = "")
 @click.argument('branches', 'The branches to backport to', nargs=-1)
-def cherry_pick(dry_run, pr_remote, commit_sha1, branches):
+def cherry_pick(dry_run, pr_remote, abort, commit_sha1, branches):
+    click.echo("\U0001F40D \U0001F352 \u26CF ")
     if not os.path.exists('./pyconfig.h.in'):
         os.chdir('./cpython/')
+
     upstream = get_git_fetch_remote()
     username = get_forked_repo_name(pr_remote)
 
     if dry_run:
        click.echo("Dry run requested, listing expected command sequence")
 
+    if abort is not None:
+        if abort:
+            abort_cherry_pick(dry_run=dry_run)
+        else:
+            continue_cherry_pick(username, pr_remote, dry_run=dry_run)
 
-    click.echo("fetching upstream ...")
-    run_cmd(f"git fetch {upstream}", dry_run=dry_run)
+    else:
+        backport_branches(commit_sha1, branches, username, upstream, pr_remote,
+                          dry_run=dry_run)
 
+def backport_branches(commit_sha1, branches, username, upstream, pr_remote,
+                      *, dry_run=False):
+    if commit_sha1 == "":
+        raise ValueError("Missing the commit_sha1 argument.")
     if not branches:
-        raise ValueError("at least one branch is required")
+        raise ValueError("At least one branch is required.")
+    else:
+        run_cmd(f"git fetch {upstream}", dry_run=dry_run)
 
-    for branch in get_sorted_branch(branches):
-        click.echo(f"Now backporting '{commit_sha1}' into '{branch}'")
+        for branch in get_sorted_branch(branches):
+            click.echo(f"Now backporting '{commit_sha1}' into '{branch}'")
 
-        # git checkout -b 61e2bc7-3.5 upstream/3.5
-        cherry_pick_branch = f"backport-{commit_sha1[:7]}-{branch}"
-        cmd = f"git checkout -b {cherry_pick_branch} {upstream}/{branch}"
-        run_cmd(cmd, dry_run=dry_run)
+            # git checkout -b backport-61e2bc7-3.5 upstream/3.5
+            cherry_pick_branch = f"backport-{commit_sha1[:7]}-{branch}"
+            pr_url = get_pr_url(username, branch, cherry_pick_branch)
+            cmd = f"git checkout -b {cherry_pick_branch} {upstream}/{branch}"
+            run_cmd(cmd, dry_run=dry_run)
 
-        cmd = f"git cherry-pick -x {commit_sha1}"
-        if run_cmd(cmd, dry_run=dry_run):
-            cmd = f"git push {pr_remote} {cherry_pick_branch}"
-            if not run_cmd(cmd, dry_run=dry_run):
-                click.echo(f"Failed to push to {pr_remote} :(")
+            cmd = f"git cherry-pick -x {commit_sha1}"
+            if run_cmd(cmd, dry_run=dry_run):
+                push_to_remote(pr_url, pr_remote, cherry_pick_branch, dry_run=dry_run)
+                cleanup_branch(cherry_pick_branch, dry_run=dry_run)
             else:
-                open_pr(username, branch, cherry_pick_branch, dry_run=dry_run)
-        else:
-            click.echo(f"Failed to cherry-pick {commit_sha1} into {branch} :(")
+                click.echo(f"Failed to cherry-pick {commit_sha1} into {branch} \u2639")
+                click.echo(" ... Stopping here. ")
+
+                click.echo("")
+                click.echo("To continue and resolve the conflict: ")
+                click.echo("    $ cd cpython")
+                click.echo("    $ git status # to find out which files need attention")
+                click.echo("    # Fix the conflict")
+                click.echo("    $ git status # should now say `all conflicts fixed`")
+                click.echo("    $ cd ..")
+                click.echo("    $ python -m cherry_picker --continue")
+
+                click.echo("")
+                click.echo("To abort the cherry-pick and cleanup: ")
+                click.echo("    $ python -m cherry_picker --abort")
+
 
-        cmd = "git checkout master"
+def abort_cherry_pick(*, dry_run=False):
+    """
+    run `git cherry-pick --abort` and then clean up the branch
+    """
+    if run_cmd("git cherry-pick --abort", dry_run=dry_run):
+        cleanup_branch(get_current_branch(), dry_run=dry_run)
+
+
+def continue_cherry_pick(username, pr_remote, *, dry_run=False):
+    """
+    git push origin <current_branch>
+    open the PR
+    clean up branch
+
+    """
+    cherry_pick_branch = get_current_branch()
+    if cherry_pick_branch != 'master':
+
+        # this has the same effect as `git cherry-pick --continue`
+        cmd = f"git commit -am 'Resolved.' --allow-empty"
         run_cmd(cmd, dry_run=dry_run)
 
-        cmd = f"git branch -D {cherry_pick_branch}"
-        if run_cmd(cmd, dry_run=dry_run):
-            if not dry_run:
-                click.echo(f"branch {cherry_pick_branch} has been deleted.")
-        else:
-            click.echo(f"branch {cherry_pick_branch} NOT deleted.")
+        base_branch = get_base_branch(cherry_pick_branch)
+        pr_url = get_pr_url(username, base_branch, cherry_pick_branch)
+        push_to_remote(pr_url, pr_remote, cherry_pick_branch, dry_run=dry_run)
+
+        cleanup_branch(cherry_pick_branch, dry_run=dry_run)
+    else:
+        click.echo(u"Refuse to push to master \U0001F61B")
+
+
+def get_base_branch(cherry_pick_branch):
+    """
+    return '2.7' from 'backport-sha-2.7'
+    """
+    return cherry_pick_branch[cherry_pick_branch.rfind('-')+1:]
+
+
+def cleanup_branch(cherry_pick_branch, *, dry_run=False):
+    """
+    git checkout master
+    git branch -D <branch to delete>
+    """
+    cmd = "git checkout master"
+    run_cmd(cmd, dry_run=dry_run)
+
+    cmd = f"git branch -D {cherry_pick_branch}"
+    if run_cmd(cmd, dry_run=dry_run):
+        if not dry_run:
+            click.echo(f"branch {cherry_pick_branch} has been deleted.")
+    else:
+        click.echo(f"branch {cherry_pick_branch} NOT deleted.")
 
+def push_to_remote(pr_url, pr_remote, cherry_pick_branch, *, dry_run=False):
+    cmd = f"git push {pr_remote} {cherry_pick_branch}"
+    if not run_cmd(cmd, dry_run=dry_run):
+        click.echo(f"Failed to push to {pr_remote} \u2639")
+    else:
+        open_pr(pr_url, dry_run=dry_run)
 
 def get_git_fetch_remote():
     """Get the remote name to use for upstream branches
@@ -70,7 +155,6 @@ def get_git_fetch_remote():
 def get_forked_repo_name(pr_remote):
     """
     Return 'myusername' out of https://github.com/myusername/cpython
-    :return:
     """
     cmd = f"git config --get remote.{pr_remote}.url"
     raw_result = subprocess.check_output(cmd.split(), stderr=subprocess.STDOUT)
@@ -94,17 +178,32 @@ def run_cmd(cmd, *, dry_run=False):
     return True
 
 
-def open_pr(forked_repo, base_branch, cherry_pick_branch, *, dry_run=False):
+def get_pr_url(forked_repo, base_branch, cherry_pick_branch):
+    """
+    construct the url for the pull request
+    """
+    return f"https://github.com/python/cpython/compare/{base_branch}...{forked_repo}:{cherry_pick_branch}?expand=1"
+
+
+def open_pr(url, *, dry_run=False):
     """
-    construct the url for pull request and open it in the web browser
+    open url in the web browser
     """
-    url = f"https://github.com/python/cpython/compare/{base_branch}...{forked_repo}:{cherry_pick_branch}?expand=1"
     if dry_run:
         click.echo(f"  dry-run: Create new PR: {url}")
         return
     webbrowser.open_new_tab(url)
 
 
+def get_current_branch():
+    """
+    Return the current branch
+    """
+    cmd = "git symbolic-ref HEAD | sed 's!refs\/heads\/!!'"
+    output = subprocess.check_output(cmd, shell=True)
+    return output.strip().decode()
+
+
 def get_sorted_branch(branches):
     return sorted(
         branches,

cherry_picker/readme.rst

@@ -1,6 +1,6 @@
 Usage::
 
-   python -m cherry_picker [--push REMOTE] [--dry-run] <commit_sha1> <branches>
+   python -m cherry_picker [--push REMOTE] [--dry-run] [--abort/--continue] <commit_sha1> <branches>
 
 
 
@@ -43,16 +43,42 @@ repository are pushed to `origin`. If this is incorrect, then the correct
 remote will need be specified using the ``--push`` option (e.g.
 ``--push pr`` to use a remote named ``pr``).
 
+
 Cherry-picking :snake: :cherries: :pick:
 ==============
 
 (Setup first! See prev section)
 
 ::
 
-    (venv) $ python -m cherry_picker <commit_sha1> <branches>
+    (venv) $ python -m cherry_picker [--dry-run] [--abort/--continue] <commit_sha1> <branches>
+
+The commit sha1 is obtained from the merged pull request on ``master``.
+
+
+Options
+-------
+
+::
+
+    -- dry-run      Dry Run Mode.  Prints out the commands, but not executed.
+    -- push REMOTE  Specify the branch to push into.  Default is 'origin'.
+
+
+Additional options::
+
+    -- abort        Abort current cherry-pick and clean up branch
+    -- continue     Continue cherry-pick, push, and clean up branch
 
-The commit sha1 is obtained from the merged pull request on ``master``. 
+
+Demo
+----
+
+https://asciinema.org/a/dfalzy45oq8b3c6dvakwfs6la
+
+
+Example
+-------
 
 For example, to cherry-pick ``6de2b7817f-some-commit-sha1-d064`` into
 ``3.5`` and ``3.6``:
@@ -82,7 +108,22 @@ What this will do:
     (venv) $ git checkout master
     (venv) $ git branch -D backport-6de2b78-3.6
 
-In case of merge conflicts or errors, then... the script will fail :stuck_out_tongue:
+In case of merge conflicts or errors, the following message will be displayed::
+
+    Failed to cherry-pick 554626ada769abf82a5dabe6966afa4265acb6a6 into 2.7 :frowning_face:
+    ... Stopping here.
+
+    To continue and resolve the conflict:
+        $ cd cpython
+        $ git status # to find out which files need attention
+        # Fix the conflict
+        $ git status # should now say `all conflicts fixed`
+        $ cd ..
+        $ python -m cherry_picker --continue
+
+    To abort the cherry-pick and cleanup:
+        $ python -m cherry_picker --abort
+
 
 Passing the `--dry-run` option will cause the script to print out all the
 steps it would execute without actually executing any of them. For example::
@@ -106,6 +147,7 @@ steps it would execute without actually executing any of them. For example::
     dry_run: git checkout master
     dry_run: git branch -D backport-1e32a1b-3.5
 
+
 Creating Pull Requests
 ======================