Skip cirq pre-release if identical to the last version

.github/workflows/release-main.yml

@@ -17,6 +17,8 @@ jobs:
       NAME: dev-release
     steps:
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          fetch-depth: 2
       - uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
         with:
           python-version: '3.11'
@@ -34,7 +36,25 @@ jobs:
       - name: Build and publish
         run: |
           CIRQ_PRE_RELEASE_VERSION=$(dev_tools/packaging/generate-dev-version-id.sh)
-          [[ "$CIRQ_PRE_RELEASE_VERSION" =~ .*dev.* ]] && echo "Deploying dev version '$CIRQ_PRE_RELEASE_VERSION'" || (echo "not dev version"; exit 1)
-          out_dir="${PWD}/dist"
-          dev_tools/packaging/produce-package.sh ${out_dir} $CIRQ_PRE_RELEASE_VERSION
+          if [[ "${CIRQ_PRE_RELEASE_VERSION}" != *.dev* ]]; then
+            echo "Not a dev version"
+            exit 1
+          fi
+          echo "Building wheels for the dev version '${CIRQ_PRE_RELEASE_VERSION}'"
+          THIS_DATE_EPOCH=$(git log -1 --pretty="%ct")
+          out_dir="${HOME}/cirq-dist"
+          out_dir_last="${HOME}/cirq-dist-last"
+          dev_tools/packaging/produce-package.sh "${out_dir}" "${CIRQ_PRE_RELEASE_VERSION}"
+          # disregard errors from building wheels at the previous commit
+          SOURCE_DATE_EPOCH=${THIS_DATE_EPOCH} dev_tools/packaging/produce-package.sh \
+            --commit="HEAD~1" "${out_dir_last}" "${CIRQ_PRE_RELEASE_VERSION}" || true
+          echo "Comparing wheels with the build at previous commit"
+          if diff -q -r "${out_dir_last}" "${out_dir}"; then
+            echo "Wheels are identical - skipping the release"
+            echo "### Skipped identical release"  >> ${GITHUB_STEP_SUMMARY}
+            echo "Cirq wheels for ${CIRQ_PRE_RELEASE_VERSION} (${GITHUB_SHA})" \
+              "are identical to their build at the previous commit." >> ${GITHUB_STEP_SUMMARY}
+            exit 0
+          fi
+          echo "Deploying dev version '$CIRQ_PRE_RELEASE_VERSION'"
           twine upload "${out_dir}/*"

dev_tools/packaging/produce-package.sh

@@ -14,62 +14,116 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-################################################################################
-# Produces wheels that can be uploaded to the pypi package repository.
-#
-# First argument must be the output directory. Second argument is an optional
-# version specifier. If not set, the version from `_version.py` is used. If set,
-# it overwrites `_version.py`.
-#
-# Usage:
-#     dev_tools/packaging/produce-package.sh output_dir [version]
-################################################################################
+set -o errexit
+set -o nounset
 
-set -e
 trap "{ echo -e '\033[31mFAILED\033[0m'; }" ERR
 
-if [ -z "${1}" ]; then
-  echo -e "\033[31mNo output directory given.\033[0m"
-  exit 1
-fi
-out_dir=$(realpath "${1}")
+DOC="\
+usage: $0 [options] output_dir [version]
+
+Produces wheels that can be uploaded to the pypi package repository.
+
+First argument must be the output directory.  Second argument is an optional
+version specifier, which overwrites the version in _version.py files.
+If not set, the version from _version.py is used as is.
 
-SPECIFIED_VERSION="${2}"
+Options:
+
+  -c, --commit=COMMIT   create wheels from sources at COMMIT instead of HEAD
+  -h, --help            display this message and exit.
+"
+
+out_dir=""
+specified_version=""
+commitish=HEAD
+
+
+die() {
+    ( shift; echo -e "\033[31m${*}\033[0m" )
+    exit "$1"
+}
 
 # Helper to isolate dev_tools/modules.py from Python environment variables
 my_dev_tools_modules() {
     python3 -E dev_tools/modules.py "$@"
 }
 
-# Get the working directory to the repo root.
+# Process command-line arguments
+while (( $# )); do
+    case "$1" in
+        -h|--help)
+            echo "$DOC"
+            exit 0
+            ;;
+        -c?*)
+            commitish="${1#-c}"
+            ;;
+        --commit=?*)
+            commitish="${1#*=}"
+            ;;
+        -c|--commit)
+            shift
+            (( $# )) || die 2 "Option '-c,--commit' requires an argument."
+            commit="$1"
+            ;;
+        *)
+            if [[ -z "${out_dir}" ]]; then
+                out_dir=$(realpath "${1}")
+            elif [[ -z "${specified_version}" ]]; then
+                specified_version="${1}"
+            else
+                die 2 "Unrecognized argument '$1'."
+            fi
+            ;;
+    esac
+    shift
+done
+
+if [[ -z "${out_dir}" ]]; then
+    die 2 "No output directory given."
+fi
+
+# Change to the root of the Cirq git repository
 thisdir=$(dirname "${BASH_SOURCE[0]:?}")
 repo_dir=$(git -C "${thisdir}" rev-parse --show-toplevel)
 cd "${repo_dir}"
 
-# Make a clean copy of HEAD, without files ignored by git (but potentially kept by setup.py).
-if [ -n "$(git status --short)" ]; then
+# Validate and resolve the commit value
+commit=$(git rev-parse --verify --quiet "${commitish}^{commit}") ||
+    die "$?" "Invalid commit identifier '${commitish}'"
+
+# Make a pristine temporary clone of the Cirq repository
+if [[ -n "$(git status --short)" ]]; then
     echo -e "\033[31mWARNING: You have uncommitted changes. They won't be included in the package.\033[0m"
 fi
+
 tmp_git_dir=$(mktemp -d "/tmp/produce-package-git.XXXXXXXXXXXXXXXX")
-trap '{ rm -rf "${tmp_git_dir}"; }' EXIT
 echo "Creating pristine repository clone at ${tmp_git_dir}"
-git clone --shared --quiet "${repo_dir}" "${tmp_git_dir}"
+git clone --shared --quiet --no-checkout "${repo_dir}" "${tmp_git_dir}"
 cd "${tmp_git_dir}"
-if [ -n "${SPECIFIED_VERSION}" ]; then
-    CURRENT_VERSION=$(my_dev_tools_modules print_version)
-    my_dev_tools_modules replace_version --old="${CURRENT_VERSION}" --new="${SPECIFIED_VERSION}"
+git checkout --quiet "${commit}"
+
+if [[ -n "${specified_version}" ]]; then
+    current_version=$(my_dev_tools_modules print_version)
+    my_dev_tools_modules replace_version --old="${current_version}" --new="${specified_version}"
 fi
 
 # Python 3 wheel.
-echo "Producing python 3 package files."
+echo "Producing Python 3 package files."
 
-CIRQ_MODULES=$(my_dev_tools_modules list --mode folder --include-parent)
-date_epoch=$(git log -1 --pretty="%ct")
+# Reuse SOURCE_DATE_EPOCH if specified in the caller environment
+date_epoch=${SOURCE_DATE_EPOCH:-$(git log -1 --pretty="%ct")}
+cirq_modules=$(my_dev_tools_modules list --mode folder --include-parent)
 
-for m in $CIRQ_MODULES; do
-  echo "creating wheel for ${m}"
-  SOURCE_DATE_EPOCH="${date_epoch}" \
-    python3 -m pip wheel --no-deps --wheel-dir="${out_dir}" "./${m}"
+for m in ${cirq_modules}; do
+    echo "creating wheel for ${m}"
+    SOURCE_DATE_EPOCH="${date_epoch}" \
+        python3 -m pip wheel --no-deps --wheel-dir="${out_dir}" "./${m}"
 done
 
 ls "${out_dir}"
+
+# Final clean up (all is well if we got here)
+cd "${repo_dir}"
+rm -rf "${tmp_git_dir}"