Introduce push-to-trunk.sh (for git users)

push-to-trunk.sh

+#! /bin/bash

[tfarina, 2011/09/06 16:08:52]

no spaces between ! and / ?

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+# Copyright 2011 the V8 project authors. All rights reserved.
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+#       copyright notice, this list of conditions and the following
+#       disclaimer in the documentation and/or other materials provided
+#       with the distribution.
+#     * Neither the name of Google Inc. nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+BRANCHNAME=prepare-push
+TRUNKBRANCH=trunk-push

[danno, 2011/09/06 09:28:55]

For safety sake, shouldn't you delete the trunk-push branch every time, too,
just like the prepare-push branch.

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+
+# Cancel if this is not a git checkout.
+[[ -d .git ]] || (
+  echo "This is not a git checkout, this script won't work for you. Exiting."
+  exit 1
+)
+
+# Cancel if EDITOR is unset or not executable.
+[[ -n "$EDITOR" && -x "$EDITOR" ]] || (
+  echo "Please set your EDITOR environment variable, you'll need it. Exiting."
+  exit 1
+)
+
+echo "Step 1: Fetch unfetched revisions."
+git svn fetch
+
+echo "Step 2: Create a fresh branch."
+if [ -n "$(git branch | grep $BRANCHNAME)" ] ; then

[mnaganov (inactive), 2011/09/05 21:02:15]

Perhaps, you need to check that this isn't the current branch, otherwise
deletion will fail.

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+  echo "Branch $BRANCHNAME exists, do you want to delete it? [Y/n]"
+  read ANSWER
+  if [ -z "$ANSWER" || "$ANSWER" == "Y" || "$ANSWER" == "y" ] ; then
+    git branch -D $BRANCHNAME
+    echo "Branch $BRANCHNAME deleted, will now re-create it."
+  else
+    echo "Can't continue. Please delete branch $BRANCHNAME and try again."
+    exit 1
+  fi
+fi
+git checkout -b $BRANCHNAME svn/bleeding_edge

[danno, 2011/09/06 09:28:55]

You probably want to check that there are no uncommitted changes on the current
branch before switching to another branch. 

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+
+echo "Step 3: Detect commit ID of last ChangeLog update."
+LASTPUSH=$(git log -1 --format=%H ChangeLog)
+
+echo "Step 4: Prepare raw ChangeLog entry."
+TEMPFILE=$(mktemp)
+# These version numbers are used again later for the trunk commit.
+MAJOR=$(grep "#define MAJOR_VERSION" src/version.cc | awk '{print $NF}')
+MINOR=$(grep "#define MINOR_VERSION" src/version.cc | awk '{print $NF}')
+BUILD=$(grep "#define BUILD_NUMBER" src/version.cc | awk '{print $NF}')
+
+DATE=$(date +%Y-%m-%d)
+echo "$DATE: Version $MAJOR.$MINOR.$BUILD" >> "$TEMPFILE"
+echo "" >> "$TEMPFILE"
+COMMITS=$(git log $LASTPUSH..HEAD --format=%H)
+for commit in $COMMITS ; do
+  # Get the commit's title line.
+  git log -1 $commit --format="%w(80,8,8)%s" >> "$TEMPFILE"
+  # Grep for "BUG=xxxx" lines in the commit message.
+  git log -1 $commit --format="%b" | grep BUG= | grep -v "BUG=$" \
+                                   | sed -e 's/^/        /' >> "$TEMPFILE"
+  # Append the commit's author for reference.
+  git log -1 $commit --format="%w(80,8,8)(%an)" >> "$TEMPFILE"
+  echo "" >> "$TEMPFILE"
+done
+
+echo "Step 5: Edit ChangeLog entry."
+echo "Please press <Return> to have your EDITOR open the ChangeLog entry, \
+then edit its contents to your liking. When you're done, save the file \
+and exit your EDITOR."
+read ANSWER
+$EDITOR "$TEMPFILE"
+NEWCHANGELOG=$(mktemp)
+# Eliminate any trailing newlines by going through a shell variable.
+CHANGELOGENTRY=$(cat "$TEMPFILE")
+[[ -n "$CHANGELOGENTRY" ]] && (
+  echo "Empty ChangeLog entry, exiting."
+  exit 1
+)
+echo "$CHANGELOGENTRY" > "$NEWCHANGELOG"
+echo "" >> "$NEWCHANGELOG" # Explicitly insert two empty lines.
+echo "" >> "$NEWCHANGELOG"
+cat ChangeLog >> "$NEWCHANGELOG"
+mv "$NEWCHANGELOG" ChangeLog
+rm -f "$TEMPFILE"
+
+echo "Step 6: Increment version number."
+echo "Please press <Return> to have your EDITOR open src/version.cc, \
+then update the version number as appropriate. When you're done, save the \
+file and exit your EDITOR."
+read ANSWER
+$EDITOR src/version.cc

[danno, 2011/09/06 09:28:55]

How about suggesting the next logical version number based on an uptick of the
build number and only requiring the editing step if the user doesn't accept the
default?

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+
+echo "Step 7: Commit to local branch."
+NEWMAJOR=$(grep "#define MAJOR_VERSION" src/version.cc | awk '{print $NF}')
+NEWMINOR=$(grep "#define MINOR_VERSION" src/version.cc | awk '{print $NF}')
+NEWBUILD=$(grep "#define BUILD_NUMBER" src/version.cc | awk '{print $NF}')
+git commit -a -m "Prepare push to trunk.  \
+Now working on version $NEWMAJOR.$NEWMINOR.$NEWBUILD."

[danno, 2011/09/06 09:28:55]

Error handling in case something goes wrong?

[Jakob Kummerow, 2011/09/07 15:46:40]

Done. I can't imagine what could go wrong here, though.

+
+echo "Step 8: Upload for code review."
+echo "Please enter the email address of a V8 reviewer for your patch:"
+read REVIEWER
+git cl upload -r $REVIEWER --send-mail

[danno, 2011/09/06 09:28:55]

You should probably allow the user to specific --prepare-push and --do-push to
do everything up to this point and after this point in two separate steps.

[Jakob Kummerow, 2011/09/07 15:46:40]

Done. Each step can be selected as entry point now.

+
+echo "Step 9: Commit to the repository."
+echo "Please wait for an LGTM, then press <Return> to commit your change."
+echo "(If you need to iterate on the patch, do so in another shell.)"
+read ANSWER

[danno, 2011/09/06 09:28:55]

If seems a bit fragile, a stray return proceeds without a LGTM. It would be neat
if you polled the generated CL every few seconds here and only proceeded if it
contained the LGTM.


Also seems really dangerous to do this without error checking the result of git
cl upload.  

[Jakob Kummerow, 2011/09/07 15:46:40]

Done: Error checking added; prevention of stray <Return> by requiring the user
to type "LGTM<Return>".

Any more sophisticated solution is postponed to possible future updates to this
script.

+git cl dcommit
+
+echo "Step 10: Fetch fresh commit from the repository."
+git svn rebase # probably not necessary, but who cares...
+

[danno, 2011/09/06 09:28:55]

I don't think this does what you want. What it somebody else committed something
to bleeding_edge in the meantime, too? Then that becomes part of the trunk push
patch, which is wrong.

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+echo "Step 11: Squash commits into one."
+# Instead of relying on "git rebase -i", we'll just create a diff, because
+# that's easier to automate.
+PATCHFILE=$(mktemp)
+git diff svn/trunk > "$PATCHFILE"
+# Convert the ChangeLog entry to commit message format:
+# - remove date
+# - remove indentation
+# - merge paragraphs into single long lines, keeping empty lines between them.
+COMMITMSG=$(mktemp)
+echo "$CHANGELOGENTRY" \
+  | sed -e "s/^$DATE: //" \
+  | sed -e 's/^ *//' \
+  | awk '{
+      if (need_space == 1) {
+        printf(" ");
+      };
+      printf("%s", $0);
+      if ($0 ~ /^$/) {
+        printf("\n\n");
+        need_space = 0;
+      } else {
+        need_space = 1;
+      }
+    }' > "$COMMITMSG"
+

[danno, 2011/09/06 09:28:55]

Might be a good idea to show the resulting commit message and ask for
verification of the contents.

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+echo "Step 12: Create a new branch from trunk."
+git checkout -b $TRUNKBRANCH svn/trunk

[mnaganov (inactive), 2011/09/05 21:02:15]

Will fail if $TRUNKBRANCH already exists for some reason. If you don't care to
overwrite an existing branch, do "git branch -f $TRUNKBRANCH svn/trunk"

[Jakob Kummerow, 2011/09/07 15:46:40]

Done: $TRUNKBRANCH now gets deleted at the beginning of the script.

+
+echo "Step 13: Apply squashed changes."
+patch -p1 < "$PATCHFILE"

[danno, 2011/09/06 09:28:55]

Should probably check for errors applying the patch and abort, just in case.

[Jakob Kummerow, 2011/09/07 15:46:40]

Done. However, due to the way the patch file is generated, I don't think it can
ever fail.

+rm -f "$PATCHFILE"
+
+echo "Step 14: Set correct version for trunk."
+sed -e "/#define MAJOR_VERSION/s/[0-9]*$/$MAJOR/" \
+    -e "/#define MINOR_VERSION/s/[0-9]*$/$MINOR/" \
+    -e "/#define BUILD_NUMBER/s/[0-9]*$/$BUILD/" \
+    -e "/#define PATCH_LEVEL/s/[0-9]*$/0/" \
+    -e "/#define IS_CANDIDATE_VERSION/s/[0-9]*$/0/" \
+    -i src/version.cc
+
+echo "Step 15: Commit to local trunk branch."
+git add src/version.cc
+git commit -F "$COMMITMSG"

[danno, 2011/09/06 09:28:55]

Error handling?

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+rm -f "$COMMITMSG"
+
+echo "Step 16: Sanity check."
+echo "Please check if your local checkout is sane: Inspect src/version.cc, \
+compile, run tests."
+echo "When you're sure you want to commit a new trunk revision to the \
+repository, press <Return>."
+read ANSWER
+
+echo "Step 17. Commit to SVN."
+git svn dcommit

[danno, 2011/09/06 09:28:55]

Error handling, you definitely don't want to make a tag without knowing the
commit worked.

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+
+echo "Step 18: Tag the new revision."
+git svn tag $MAJOR.$MINOR.$BUILD -m "Tagging version $MAJOR.$MINOR.$BUILD"
+
+echo "Step 19: Cleanup."
+git checkout -f master

[danno, 2011/09/06 09:28:55]

Not everybody has a master (like me). You probably should remember the current
branch from which you started the script and change back to that, it's more user
friendly.

[Jakob Kummerow, 2011/09/07 15:46:40]

Done.

+git branch -D $BRANCHNAME
+git branch -D $TRUNKBRANCH
+
+echo "Step 20: Done!"
+echo "Congratulations, you have successfully created the trunk revision \
+$MAJOR.$MINOR.$BUILD."
+echo "Please don't forget to update the v8rel spreadsheet, and \

[danno, 2011/09/06 09:28:55]

For extra points and the respect of the entire team, automatically update v8rel
using http://code.google.com/apis/spreadsheets/ :-)

[Jakob Kummerow, 2011/09/07 15:46:40]

Advanced feature -> post-V1 ;-)

+to roll this new version into Chromium."