chore: add pr code coverage to ci (#4643)

ci/partials/code-coverage-diff.yml

@@ -0,0 +1,15 @@
+platform: linux
+inputs:
+  - name: src
+  - name: pipeline-tasks
+outputs: [name: src]
+params:
+  GH_EMAIL: ((pages-operations-github-user-info.email))
+  GH_USERNAME: ((pages-operations-github-user-info.username))
+  GH_BOT_GPG_KEY: ((pages-operations-github-user-gpg.private_key))
+  GH_BOT_SSH_KEY: ((pages-gpg-operations-github-sshkey.private_key))
+  GH_BOT_GPG_TRUST: ((pages-operations-github-user-gpg-trust))
+  GH_TOKEN: ((pages-operations-ci-github-token))
+run:
+  dir: src
+  path: ci/tasks/code-coverage-diff.sh

ci/pipeline.yml

@@ -75,6 +75,17 @@ jobs:
         instance_vars:
           deploy-env: ((deploy-env))
 
+  #@ if/end env == 'dev':
+  - name: code-coverage-diff
+    plan:
+      - get: src
+        trigger: true
+      - get: node
+      - get: pipeline-tasks
+      - task: code-coverage-diff
+        image: node
+        file: src/ci/partials/code-coverage-diff.yml
+
   #@ if/end env == 'staging':
   - name: update-release-branch
     plan:

ci/tasks/code-coverage-diff.sh

@@ -0,0 +1,28 @@
+#!/bin/bash
+
+set -e
+
+source "$(dirname $PWD)/pipeline-tasks/scripts/github-setup.sh"
+
+apt-get install jq
+
+# note our branch
+branch=$(git rev-parse --abbrev-ref HEAD)
+
+# generate test coverage
+yarn install
+cov_cmd="yarn test:rtl --coverageReporters json-summary --coverageDirectory tmp"
+tot_cmd="jq '.["total"]["lines"]["pct"]' tmp/coverage-summary.json"
+bash -c $cov_cmd
+newcc=$(bash -c $tot_cmd)
+git checkout main
+bash -c $cov_cmd
+oldcc=$(bash -c $tot_cmd)
+
+difcc=$(($newcc-$oldcc))
+
+gh pr comment $branch -b " \
+  ## :robot: This is an automated code coverage report
+  Total coverage (lines): $newcc%
+  Coverage diff: $diffcc%
+"