ci: skip heavy checks in Release Please SNAPSHOT pull requests (#11323)

Author: suztomo

.kokoro/build.sh

@@ -54,7 +54,9 @@ case ${JOB_TYPE} in
     ;;
   integration)
     generate_modified_modules_list
-    if [[ ${#modified_module_list[@]} -gt 0 ]]; then
+    if [[ "$(release_please_snapshot_pull_request)" == "true" ]]; then
+      echo "Skipping integration tests as this is Release Please SNAPSHOT pull request."
+    elif [[ ${#modified_module_list[@]} -gt 0 ]]; then
       module_list=$(
         IFS=,
         echo "${modified_module_list[*]}"
@@ -68,14 +70,20 @@ case ${JOB_TYPE} in
     ;;
   graalvm-presubmit)
     generate_graalvm_presubmit_modules_list
-    printf "Running GraalVM presubmit checks for:\n%s\n" "${module_list}"
-    setup_cloud "$module_list"
-    install_modules "$module_list"
-    run_graalvm_tests "$module_list"
+    if [[ "$(release_please_snapshot_pull_request)" == "true" ]]; then
+      echo "Not running GraalVM checks -- this is Release Please SNAPSHOT pull request."
+    else
+      printf "Running GraalVM presubmit checks for:\n%s\n" "${module_list}"
+      setup_cloud "$module_list"
+      install_modules "$module_list"
+      run_graalvm_tests "$module_list"
+    fi
     ;;
   graalvm)
     generate_graalvm_modules_list
-    if [ ! -z "${module_list}" ]; then
+    if [[ "$(release_please_snapshot_pull_request)" == "true" ]]; then
+      echo "Not running GraalVM checks -- this is Release Please SNAPSHOT pull request."
+    elif [ ! -z "${module_list}" ]; then
       printf "Running GraalVM checks for:\n%s\n" "${module_list}"
       setup_cloud "$module_list"
       install_modules "$module_list"

.kokoro/common.sh

@@ -140,6 +140,21 @@ function setup_cloud() {
   trap destroy EXIT
 }
 
+# Prints "true" if this pull pull request is made by Release Please
+# SNAPSHOT pull request.
+# If a CI runs on a Release Please SNAPSHOT pull request, there's no point in running
+# integration tests because it only changes the versions in pom.xml and we merge
+# the pull requests without any additional changes (b/370011322).
+function release_please_snapshot_pull_request() {
+  # Example value: "+google-cloud-java:1.48.0:1.49.0-SNAPSHOT"
+  changedLine=$(git diff origin/main -- versions.txt 2>/dev/null | grep '^+google-cloud-java:')
+  if [[ "$changedLine" =~ "SNAPSHOT"$ ]]; then
+    echo "true"
+  else
+    echo "false"
+  fi
+}
+
 function generate_modified_modules_list() {
   # Find the files changed from when the PR branched to the last commit
   # Filter for java modules and get all the unique elements