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

tools/push-to-trunk.sh

Index: tools/push-to-trunk.sh
diff --git a/tools/push-to-trunk.sh b/tools/push-to-trunk.sh
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+#!/bin/bash
+# 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.
+
+
+########## Global variable definitions
+
+BRANCHNAME=prepare-push
+TRUNKBRANCH=trunk-push
+TEMP_BRANCH=v8-push-to-trunk-script-temporary-branch
+VERSION_FILE="src/version.cc"
+PERSISTFILE_BASENAME=/tmp/v8-push-to-trunk-tempfile
+CHANGELOG_ENTRY_FILE="$PERSISTFILE_BASENAME-changelog-entry"
+PATCH_FILE="$PERSISTFILE_BASENAME-patch"
+COMMITMSG_FILE="$PERSISTFILE_BASENAME-commitmsg"
+TOUCHED_FILES_FILE="$PERSISTFILE_BASENAME-touched-files"
+STEP=0
+
+
+########## Function definitions
+
+usage() {
+cat << EOF
+usage: $0 OPTIONS
+
+Performs the necessary steps for a V8 push to trunk. Only works for \
+git checkouts.
+
+OPTIONS:
+  -h    Show this message
+  -s    Specify the step where to start work. Default: 0.
+  -l    Manually specify the git commit ID of the last push to trunk.
+EOF
+}
+
+die() {
+  [[ -n "$1" ]] && echo "Error: $1"
+  echo "Exiting."
+  exit 1
+}
+
+confirm() {
+  echo -n "$1 [Y/n] "
+  read ANSWER
+  if [[ -z "$ANSWER" || "$ANSWER" == "Y" || "$ANSWER" == "y" ]] ; then
+    return 0
+  else
+    return 1
+  fi
+}
+
+delete_branch() {
+  local MATCH=$(git branch | grep $1)
+  if [ "$MATCH" == "$1" ] ; then
+    confirm "Branch $1 exists, do you want to delete it?"
+    if [ $? -eq 0 ] ; then
+      git branch -D $1
+      echo "Branch $1 deleted."
+    else
+      die "Can't continue. Please delete branch $1 and try again."
+    fi
+  fi
+}
+
+# Persist and restore variables to support canceling/resuming execution
+# of this script.
+persist() {
+  local VARNAME=$1
+  local FILE="$PERSISTFILE_BASENAME-$VARNAME"
+  echo "${!VARNAME}" > $FILE
+}
+
+restore() {
+  local VARNAME=$1
+  local FILE="$PERSISTFILE_BASENAME-$VARNAME"
+  local VALUE="$(cat $FILE)"
+  eval "$VARNAME=\"$VALUE\""
+}
+
+restore_if_unset() {
+  local VARNAME=$1
+  [[ -z "${!VARNAME}" ]] && restore "$VARNAME"
+  [[ -z "${!VARNAME}" ]] && die "Variable '$VARNAME' could not be restored."
+}
+
+
+########## Option parsing
+
+while getopts ":hs:l:" OPTION ; do
+  case $OPTION in
+    h)  usage
+        exit 0
+        ;;
+    s)  STEP=$OPTARG
+        ;;
+    l)  LASTPUSH=$OPTARG
+        ;;
+    ?)  echo "Illegal option: -$OPTARG"
+        usage
+        exit 1
+        ;;
+  esac
+done
+
+
+########## Regular workflow
+
+# Cancel if this is not a git checkout.
+[[ -d .git ]] \
+  || die "This is not a git checkout, this script won't work for you."
+
+# Cancel if EDITOR is unset or not executable.
+[[ -n "$EDITOR" && -x "$(which $EDITOR)" ]] \
+  || die "Please set your EDITOR environment variable, you'll need it."
+
+if [ $STEP -le 0 ] ; then
+  echo ">>> Step 0: Preparation"
+  # Check for a clean workdir.
+  [[ -z "$(git status -s -uno)" ]] \
+    || die "Workspace is not clean. Please commit or undo your changes."
+
+  # Persist current branch.
+  CURRENT_BRANCH=$(git status -s -b -uno | grep "^##" | awk '{print $2}')
+  persist "CURRENT_BRANCH"
+  # Get ahold of a safe temporary branch and check it out.
+  if [ "$CURRENT_BRANCH" != "$TEMP_BRANCH" ] ; then
+    delete_branch $TEMP_BRANCH
+    git checkout -b $TEMP_BRANCH
+  fi
+  # Delete branches if they exist.
+  delete_branch $BRANCHNAME
+  delete_branch $TRUNKBRANCH
+fi
+
+if [ $STEP -le 1 ] ; then
+  echo ">>> Step 1: Fetch unfetched revisions."
+  git svn fetch || die "'git svn fetch' failed."
+fi
+
+if [ $STEP -le 2 ] ; then
+  echo ">>> Step 2: Create a fresh branch."
+  git checkout -b $BRANCHNAME svn/bleeding_edge \
+    || die "Creating branch $BRANCHNAME failed."
+fi
+
+if [ $STEP -le 3 ] ; then
+  echo ">>> Step 3: Detect commit ID of last push to trunk."
+  [[ -n "$LASTPUSH" ]] || LASTPUSH=$(git log -1 --format=%H ChangeLog)
+  LOOP=1
+  while [ $LOOP -eq 1 ] ; do
+    # Print assumed commit, circumventing git's pager.
+    git log -1 $LASTPUSH | cat
+    confirm "Is the commit printed above the last push to trunk?"
+    if [ $? -eq 0 ] ; then
+      LOOP=0
+    else
+      LASTPUSH=$(git log -1 --format=%H $LASTPUSH^ ChangeLog)
+    fi
+  done
+  persist "LASTPUSH"
+fi
+
+if [ $STEP -le 4 ] ; then
+  echo ">>> Step 4: Prepare raw ChangeLog entry."
+# These version numbers are used again later for the trunk commit.
+  MAJOR=$(grep "#define MAJOR_VERSION" "$VERSION_FILE" | awk '{print $NF}')
+  persist "MAJOR"
+  MINOR=$(grep "#define MINOR_VERSION" "$VERSION_FILE" | awk '{print $NF}')
+  persist "MINOR"
+  BUILD=$(grep "#define BUILD_NUMBER" "$VERSION_FILE" | awk '{print $NF}')
+  persist "BUILD"
+
+  DATE=$(date +%Y-%m-%d)
+  persist "DATE"
+  echo "$DATE: Version $MAJOR.$MINOR.$BUILD" > "$CHANGELOG_ENTRY_FILE"
+  echo "" >> "$CHANGELOG_ENTRY_FILE"
+  COMMITS=$(git log $LASTPUSH..HEAD --format=%H)
+  for commit in $COMMITS ; do
+    # Get the commit's title line.
+    git log -1 $commit --format="%w(80,8,8)%s" >> "$CHANGELOG_ENTRY_FILE"
+    # Grep for "BUG=xxxx" lines in the commit message.
+    git log -1 $commit --format="%b" | grep BUG= | grep -v "BUG=$" \
+                                     | sed -e 's/^/        /' \
+                                     >> "$CHANGELOG_ENTRY_FILE"
+    # Append the commit's author for reference.
+    git log -1 $commit --format="%w(80,8,8)(%an)" >> "$CHANGELOG_ENTRY_FILE"
+    echo "" >> "$CHANGELOG_ENTRY_FILE"
+  done
+fi
+
+if [ $STEP -le 5 ] ; then
+  echo ">>> Step 5: Edit ChangeLog entry."
+  echo -n "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
+  $EDITOR "$CHANGELOG_ENTRY_FILE"
+  NEWCHANGELOG=$(mktemp)
+  # Eliminate any trailing newlines by going through a shell variable.
+  CHANGELOGENTRY=$(cat "$CHANGELOG_ENTRY_FILE")
+  [[ -n "$CHANGELOGENTRY" ]] || die "Empty ChangeLog entry."
+  echo "$CHANGELOGENTRY" > "$NEWCHANGELOG"
+  echo "" >> "$NEWCHANGELOG" # Explicitly insert two empty lines.
+  echo "" >> "$NEWCHANGELOG"
+  cat ChangeLog >> "$NEWCHANGELOG"
+  mv "$NEWCHANGELOG" ChangeLog
+fi
+
+if [ $STEP -le 6 ] ; then
+  echo ">>> Step 6: Increment version number."
+  restore_if_unset "BUILD"
+  NEWBUILD=$(($BUILD + 1))
+  confirm "Automatically increment BUILD_NUMBER? (Saying 'n' will fire up \
+your EDITOR on $VERSION_FILE so you can make arbitrary changes. When \
+you're done, save the file and exit your EDITOR.)"
+  if [ $? -eq 0 ] ; then
+    sed -e "/#define BUILD_NUMBER/s/[0-9]*$/$NEWBUILD/" \
+        -i "$VERSION_FILE"
+  else
+    $EDITOR "$VERSION_FILE"
+  fi
+  NEWMAJOR=$(grep "#define MAJOR_VERSION" "$VERSION_FILE" | awk '{print $NF}')
+  persist "NEWMAJOR"
+  NEWMINOR=$(grep "#define MINOR_VERSION" "$VERSION_FILE" | awk '{print $NF}')
+  persist "NEWMINOR"
+  NEWBUILD=$(grep "#define BUILD_NUMBER" "$VERSION_FILE" | awk '{print $NF}')
+  persist "NEWBUILD"
+fi
+
+if [ $STEP -le 7 ] ; then
+  echo ">>> Step 7: Commit to local branch."
+  restore_if_unset "NEWMAJOR"
+  restore_if_unset "NEWMINOR"
+  restore_if_unset "NEWBUILD"
+  git commit -a -m "Prepare push to trunk.  \
+Now working on version $NEWMAJOR.$NEWMINOR.$NEWBUILD." \
+    || die "'git commit -a' failed."
+fi
+
+if [ $STEP -le 8 ] ; then
+  echo ">>> Step 8: Upload for code review."
+  echo -n "Please enter the email address of a V8 reviewer for your patch: "
+  read REVIEWER
+  git cl upload -r $REVIEWER --send-mail \
+    || die "'git cl upload' failed, please try again."
+fi
+
+if [ $STEP -le 9 ] ; then
+  echo ">>> Step 9: Commit to the repository."
+  echo "Please wait for an LGTM, then type \"LGTM<Return>\" to commit your \
+change. (If you need to iterate on the patch, do so in another shell.)"
+  unset ANSWER
+  while [ "$ANSWER" != "LGTM" ] ; do
+    [[ -n "$ANSWER" ]] && echo "That was not 'LGTM'."
+    echo -n "> "
+    read ANSWER
+  done
+  # Re-read the ChangeLog entry (to pick up possible changes).
+  cat ChangeLog | awk --posix '{
+    if ($0 ~ /^[0-9]{4}-[0-9]{2}-[0-9]{2}:/) {
+      if (in_firstblock == 1) {
+        exit 0;
+      } else {
+        in_firstblock = 1;
+      }
+    };
+    print $0;
+  }' > "$CHANGELOG_ENTRY_FILE"
+  git cl dcommit || die "'git cl dcommit' failed, please try again."
+fi
+
+if [ $STEP -le 10 ] ; then
+  echo ">>> Step 10: NOP"
+  # Present in the manual guide, not necessary (even harmful!) for this script.
+fi
+
+if [ $STEP -le 11 ] ; then
+  echo ">>> Step 11: Squash commits into one."
+  # Instead of relying on "git rebase -i", we'll just create a diff, because
+  # that's easier to automate.
+  git diff svn/trunk > "$PATCH_FILE"
+  # Convert the ChangeLog entry to commit message format:
+  # - remove date
+  # - remove indentation
+  # - merge paragraphs into single long lines, keeping empty lines between them.
+  restore_if_unset "DATE"
+  CHANGELOGENTRY=$(cat "$CHANGELOG_ENTRY_FILE")
+  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_FILE" || die "Commit message editing failed."
+  LOOP=1
+  while [ $LOOP -eq 1 ] ; do
+    echo "This is the trunk commit message:"
+    echo "--------------------"
+    cat "$COMMITMSG_FILE"
+    echo -e "\n--------------------"
+    confirm "Does this look good to you? (Saying 'n' will fire up your \
+EDITOR so you can change the commit message. When you're done, save the \
+file and exit your EDITOR.)"
+    if [ $? -eq 0 ] ; then
+      LOOP=0
+    else
+      $EDITOR "$COMMITMSG_FILE"
+    fi
+  done
+  rm -f "$CHANGELOG_ENTRY_FILE"
+fi
+
+if [ $STEP -le 12 ] ; then
+  echo ">>> Step 12: Create a new branch from trunk."
+  git checkout -b $TRUNKBRANCH svn/trunk \
+    || die "Checking out a new branch '$TRUNKBRANCH' failed."
+fi
+
+if [ $STEP -le 13 ] ; then
+  echo ">>> Step 13: Apply squashed changes."
+  patch -p1 < "$PATCH_FILE" | tee >(awk '{print $NF}' >> "$TOUCHED_FILES_FILE")
+  [[ $? -eq 0 ]] || die "Applying the patch to trunk failed."
+  TOUCHED_FILES=$(cat "$TOUCHED_FILES_FILE")
+  for FILE in $TOUCHED_FILES ; do
+    git add "$FILE"
+  done
+  rm -f "$PATCH_FILE"
+  rm -f "$TOUCHED_FILES_FILE"
+fi
+
+if [ $STEP -le 14 ] ; then
+  echo ">>> Step 14: Set correct version for trunk."
+  restore_if_unset "MAJOR"
+  restore_if_unset "MINOR"
+  restore_if_unset "BUILD"
+  sed -e "/#define MAJOR_VERSION/s/[0-9]*$/$MAJOR/" \
+      -e "/#define MINOR_VERSION/s/[0-9]*$/$MINOR/" \
+      -e "/#define BUILD_NUMBER/s/[0-9]*$/$BUILD/" \
+      -e "/#define PATCH_LEVEL/s/[0-9]*$/0/" \
+      -e "/#define IS_CANDIDATE_VERSION/s/[0-9]*$/0/" \
+      -i "$VERSION_FILE" || die "Patching $VERSION_FILE failed."
+fi
+
+if [ $STEP -le 15 ] ; then
+  echo ">>> Step 15: Commit to local trunk branch."
+  git add "$VERSION_FILE"
+  git commit -F "$COMMITMSG_FILE" || die "'git commit' failed."
+  rm -f "$COMMITMSG_FILE"
+fi
+
+if [ $STEP -le 16 ] ; then
+  echo ">>> Step 16: Sanity check."
+  confirm "Please check if your local checkout is sane: Inspect $VERSION_FILE, \
+compile, run tests. Do you want to commit this new trunk revision to the \
+repository?"
+  [[ $? -eq 0 ]] || die "Execution canceled."
+fi
+
+if [ $STEP -le 17 ] ; then
+  echo ">>> Step 17. Commit to SVN."
+  git svn dcommit || die "'git svn dcommit' failed."
+fi
+
+if [ $STEP -le 18 ] ; then
+  echo ">>> Step 18: Tag the new revision."
+  restore_if_unset "MAJOR"
+  restore_if_unset "MINOR"
+  restore_if_unset "BUILD"
+  git svn tag $MAJOR.$MINOR.$BUILD -m "Tagging version $MAJOR.$MINOR.$BUILD" \
+    || die "'git svn tag' failed."
+fi
+
+if [ $STEP -le 19 ] ; then
+  echo ">>> Step 19: Cleanup."
+  restore_if_unset "CURRENT_BRANCH"
+  git checkout -f $CURRENT_BRANCH
+  [[ "$TEMP_BRANCH" != "$CURRENT_BRANCH" ]] && git branch -D $TEMP_BRANCH
+  [[ "$BRANCHNAME" != "$CURRENT_BRANCH" ]] && git branch -D $BRANCHNAME
+  [[ "$TRUNKBRANCH" != "$CURRENT_BRANCH" ]] && git branch -D $TRUNKBRANCH
+fi
+
+if [ $STEP -le 20 ] ; then
+  echo ">>> Step 20: Done!"
+  restore_if_unset "MAJOR"
+  restore_if_unset "MINOR"
+  restore_if_unset "BUILD"
+  echo "Congratulations, you have successfully created the trunk revision \
+$MAJOR.$MINOR.$BUILD. Please don't forget to update the v8rel spreadsheet, \
+and to roll this new version into Chromium."
+  # Clean up all temporary files.
+  rm -f "$PERSISTFILE_BASENAME"*
+fi