Create CI build script for spm quickstarts (#1253)

* Add universal spm ci script

* Remove redundant exit status

* Add spm test script

* Fix unbound variable

Author: jrcrespoh

.github/workflows/abtesting.yml

@@ -47,15 +47,12 @@ jobs:
           LEGACY: true
       - name: Build and Test SwiftUI
         run: |
-          cd abtesting
-          ../scripts/install_prereqs/abtesting.sh
-          xcodebuild \
-          -project 'ABTestingExample.xcodeproj' \
-          -scheme 'ABTestingExample (iOS)' \
-          -sdk iphonesimulator \
-          -destination 'platform=iOS Simulator,name=iPhone 11' \
-          build \
-          test \
-          | xcpretty
+          ./scripts/test_spm.sh
         env:
           SAMPLE: ABTesting
+          DIR: abtesting
+          OS: iOS
+          PLATFORM: iphone
+          DEVICE: iPhone 11
+          SWIFT_DEFINES: ""
+          secrets_passphrase: ${{ secrets.GHASECRETSGPGPASSPHRASE1 }}

scripts/test_spm.sh

@@ -0,0 +1,51 @@
+#!/usr/bin/env bash
+
+# Copyright 2021 Google
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+# Build the quickstart. If we're running on the main repo (not a fork), we
+# also run the tests along with the decoded GoogleService-Info.plist files.
+
+set -euo pipefail
+
+# Set have_secrets to true or false.
+have_secrets=false
+
+. ./scripts/check_secrets.sh
+
+if [[ "$have_secrets" == true ]]; then
+    xcodebuild \
+     -project "${DIR}/${SAMPLE}Example.xcodeproj" \
+     -scheme "${SAMPLE}Example (${OS})" \
+     -sdk "${PLATFORM}simulator" \
+     -destination "platform=${OS} Simulator,name=${DEVICE}" \
+     build \
+     test \
+     ONLY_ACTIVE_ARCH=YES \
+     OTHER_SWIFT_FLAGS=${SWIFT_DEFINES} \
+     | xcpretty
+else
+    # Skip running tests if GoogleService-Info.plist's weren't decoded.
+    xcodebuild \
+     -project "${DIR}/${SAMPLE}Example.xcodeproj" \
+     -scheme "${SAMPLE}Example (${OS})" \
+     -sdk "${PLATFORM}simulator" \
+     -destination "platform=${OS} Simulator,name=${DEVICE}" \
+     build \
+     ONLY_ACTIVE_ARCH=YES \
+     OTHER_SWIFT_FLAGS=${SWIFT_DEFINES} \
+     | xcpretty
+    echo "Missing secrets: tests did not run."
+fi