ci: add yarn cache for material-unit tests job (#29378)

PR Close #29378

.circleci/config.yml

@@ -563,7 +563,24 @@ jobs:
     steps:
       - *attach_workspace
       - *init_environment
-      - run: ./scripts/ci/run_angular_material_unit_tests.sh
+      - run:
+          name: "Determining SHA of Material Ivy branch"
+          command: git ls-remote ${MATERIAL_REPO_URL} ${MATERIAL_REPO_BRANCH} | cut -f1 > material_repo_sha
+      - run:
+          name: "Cloning Material repository"
+          command: ./scripts/ci/clone_angular_material_repo.sh
+      - restore_cache:
+          keys:
+            - v1-angular-material-{{ checksum "material_repo_sha" }}
+            - v1-angular-material-
+      - run:
+          name: "Running Material unit tests"
+          command: ./scripts/ci/run_angular_material_unit_tests.sh
+      - save_cache:
+          key: v1-angular-material-{{ checksum "material_repo_sha" }}
+          paths:
+            # Needs to be hardcoded because environment variables are not interpolated here.
+            - "/tmp/material2/node_modules"
 
 workflows:
   version: 2

.circleci/env.sh

@@ -62,6 +62,15 @@ setPublicVar SAUCE_TUNNEL_IDENTIFIER "angular-${CIRCLE_BUILD_NUM}-${CIRCLE_NODE_
 # acquire CircleCI instances for too long if sauceconnect failed, we need a connect timeout.
 setPublicVar SAUCE_READY_FILE_TIMEOUT 120
 
+####################################################################################################
+# Define environment variables for the Angular Material unit tests job.
+####################################################################################################
+# We specifically use a directory within "/tmp" here because we want the cloned repo to be
+# completely isolated from angular/angular in order to avoid any bad interactions between
+# their separate build setups.
+setPublicVar MATERIAL_REPO_TMP_DIR "/tmp/material2"
+setPublicVar MATERIAL_REPO_URL "https://github.com/angular/material2.git"
+setPublicVar MATERIAL_REPO_BRANCH "ivy-2019"
 
 # Source `$BASH_ENV` to make the variables available immediately.
 source $BASH_ENV;

scripts/ci/clone_angular_material_repo.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+
+set -u -e -o pipefail
+
+# Ensure that the temporary directory does not exist.
+rm -rf ${MATERIAL_REPO_TMP_DIR}
+
+# Clone the Material repository into the given temporary directory.
+git clone --depth 1 --branch ${MATERIAL_REPO_BRANCH} ${MATERIAL_REPO_URL} \
+  ${MATERIAL_REPO_TMP_DIR}

scripts/ci/run_angular_material_unit_tests.sh

@@ -1,36 +1,28 @@
 #!/usr/bin/env bash
 set -u -e -o pipefail
 
-
 # This script runs unit tests from angular/material2.
 
 # Save the dir for the root of the Angular repo.
 angular_dir=$(pwd)
 
-# Clone the angular/material2 repo into tmp so we can run the tests from there.
+# Switch into Material directory.
-# We specifically use /tmp here because we want the cloned repo to be completely
+cd ${MATERIAL_REPO_TMP_DIR}
-# isolated from angular/angular in order to avoid any bad interactions between their
-# separate build setups. Also note that this is using the ivy-2019 branch, which has
-# previously been set up to work with ivy.
-cd /tmp
-rm -rf /tmp/material2
-git clone --depth 1 --branch ivy-2019 https://github.com/angular/material2.git
 
 # Install dependencies for the freshly cloned repo.
-cd /tmp/material2
+yarn install --frozen-lockfile --non-interactive
-yarn install --frozen-lockfile --non-interactive # TODO: cache
 
 # Install this version of Angular into the freshly cloned repo.
-rm -rf /tmp/material2/node_modules/@angular/*
+rm -rf ./node_modules/@angular/*
-cp -r ${angular_dir}/dist/packages-dist-ivy-aot/* /tmp/material2/node_modules/@angular/
+cp -r ${angular_dir}/dist/packages-dist-ivy-aot/* ./node_modules/@angular/
 
-# The angular/material2 CI sets TEST_PLATFORM to either local, saucelabs, or browserstack.
+# The angular/material2 CI sets TEST_PLATFORM to either "local", "saucelabs", or "browserstack".
-# For angular/angular, we only want to run the local tests.
+# For angular/angular, we only want to run the "local" tests.
 export TEST_PLATFORM=local
 
 # Append the test blocklist into angular/material2's karma-test-shim.js.
 # This filters out known-failing tests because the goal is to prevent regressions.
-cat ${angular_dir}/tools/material-ci/angular_material_test_blocklist.js >> /tmp/material2/test/karma-test-shim.js
+cat ${angular_dir}/tools/material-ci/angular_material_test_blocklist.js >> ./test/karma-test-shim.js
 
 # Now actually run the tests.
 yarn gulp test:single-run