check/build-changed-protos

#!/usr/bin/env bash

################################################################################
# Runs bazel build for proto files in cirq/google/api/* that have changed.
#
# If any BUILD file for the proto has changed, all targets in that BUILD
# file will be built.
#
# Usage:
#     check/build-changed-protos [BASE_REVISION]
#
# You can specify a base git revision to compare against (i.e. to use when
# determining whether or not a line is considered to have "changed"). For
# example, you can compare against 'origin/main' or 'HEAD~1'.
#
# If you don't specify a base revision, the following defaults will be tried, in
# order, until one exists:
#
#     1. upstream/main
#     2. origin/main
#     3. main
#
# If none exists, the script fails.
#
# See build-protos for building all protos.
################################################################################

# Get the working directory to the repo root.
thisdir="$(dirname "${BASH_SOURCE[0]}")" || exit $?
topdir="$(git -C "${thisdir}" rev-parse --show-toplevel)" || exit $?
cd "${topdir}" || exit $?

# Figure out which revision to compare against.
if [ -n "$1" ] && [[ $1 != -* ]]; then
    if ! git rev-parse --verify --quiet --no-revs "$1^{commit}"; then
        echo -e "\033[31mNo revision '$1'.\033[0m" >&2
        exit 1
    fi
    rev=$1
elif [ "$(git cat-file -t upstream/main 2> /dev/null)" == "commit" ]; then
    rev=upstream/main
elif [ "$(git cat-file -t origin/main 2> /dev/null)" == "commit" ]; then
    rev=origin/main
elif [ "$(git cat-file -t main 2> /dev/null)" == "commit" ]; then
    rev=main
else
    echo -e "\033[31mNo default revision found to compare against. Argument #1 must be what to diff against (e.g. 'origin/main' or 'HEAD~1').\033[0m" >&2
    exit 1
fi
base="$(git merge-base "${rev}" HEAD)"
if [ "$(git rev-parse "${rev}")" == "${base}" ]; then
    echo -e "Comparing against revision '${rev}'." >&2
else
    echo -e "Comparing against revision '${rev}' (merge base ${base})." >&2
    rev="${base}"
fi

# All the protos.
echo "Building protos in $PWD"

dev_tools/build-protos.sh

# Filenames with spaces will be ugly (each part will be listed separately)
# but the error logic will still work.
uncommitted=$(git status --porcelain 2>/dev/null | grep -E "^[?][?] cirq-google" | cut -d " " -f 3)

if [[ -n "$uncommitted" ]]; then
    echo -e "\033[31mERROR: Uncommitted generated files found! Please generate and commit these files using dev_tools/build-protos.sh:\033[0m"
    for generated in $uncommitted
    do
        echo -e "\033[31m   ${generated}\033[0m"
    done
    exit 1
fi