Convert lit.dev to npm workspaces (#862)

Replaces Lerna with npm workspaces.

### Issues encountered

- npm workspaces hoists shared dependencies, so there were a few spots where we were assuming that `playground-elements` would get installed to `<root>/packages/lit-dev-content/node_modules/playground-elements`, but it now gets installed to `<root>/node_modules/playground-elements` Updated these spots.

- Constrained our typescript version with a `~`, because there is a new breaking change I didn't want to address in this PR, and `~` is a good idea anyway because TypeScript doesn't follow semver.

- There seems a problem in the integration tests where running it a second time causes an error because the server is already running. This seems to be because playwright sends a `SIGKILL` instead of a `SIGTERM` or `SIGINT` to shut down the server, which I think causes the server to not shut down correctly (perhaps because it is a child of `npm` and `run-p`), so it keeps running after an integration test (see microsoft/playwright#12299). This means that we can't get updated goldens after a screenshot failure, because that works by running the integration tests again with a special option enabled. For now I have enabled the `reuseExistingServer` option as a workaround. Wireit services will also solve this: google/wireit#33.

### Also

- Upgraded to the latest playground-elements
- Upgraded to the latest MWC.
- Upgraded to the latest Wireit.

- Moved the playground-elements dependency to the top-level, since it gets installed there anyway, and now there will only be one place to change the version constraint, instead of 3.

- Added some logging to the static playground renderer, so that we get more information when it times out (e.g. in this case there was a 404 that wasn't getting displayed in the build logs).

-  Split apart check links workflow from integration tests workflow. Just seems nicer to view them separately.

Author: aomarks

.github/workflows/check-api-data-in-sync.yml

@@ -18,9 +18,9 @@ jobs:
       - uses: google/wireit@setup-github-actions-caching/v1
         with:
           node-version: 18
-          # Don't cache because we don't fully bootstrap
+          cache: npm
+          cache-dependency-path: '**/package-lock.json'
 
       - run: npm ci
-      - run: npx lerna bootstrap --scope lit-dev-api --include-dependencies
-      - run: npx lerna run build --scope lit-dev-api --include-dependencies
+      - run: npm run build --workspace=lit-dev-api
       - run: command test -z "$(git status --porcelain)"

.github/workflows/check-format.yml

@@ -11,7 +11,8 @@ jobs:
       - uses: actions/setup-node@v2
         with:
           node-version: 18
-          # Don't cache because we don't bootstrap
+          cache: npm
+          cache-dependency-path: '**/package-lock.json'
 
       - run: npm ci
       - run: npm run format:check

.github/workflows/check-links.yml

@@ -0,0 +1,19 @@
+name: Check links
+
+on: [push, pull_request]
+
+jobs:
+  check-links:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - uses: google/wireit@setup-github-actions-caching/v1
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: 18
+          cache: npm
+          cache-dependency-path: '**/package-lock.json'
+
+      - run: npm ci
+      - run: npm run test:links

.github/workflows/integration-tests.yml

@@ -17,8 +17,6 @@ jobs:
 
       - run: npm ci
       - run: npx playwright install-deps
-      - run: npm run bootstrap
-      - run: npm run test:links
       - id: test
         run: npm run test:integration
 

.github/workflows/unit-tests.yml

@@ -16,5 +16,4 @@ jobs:
           cache-dependency-path: '**/package-lock.json'
 
       - run: npm ci
-      - run: npm run bootstrap
       - run: npm run test:unit

.gitignore

@@ -20,6 +20,5 @@ packages/lit-dev-tests/src/playwright/**/*.png
 test-results
 
 *.tsbuildinfo
-lerna-debug.log
 
 .wireit

Dockerfile

@@ -23,19 +23,19 @@ WORKDIR /usr/src/app
 # to execute the final Eleventy build step.
 
 # External dependencies
-COPY package*.json lerna.json tsconfig.base.json ./
+COPY package*.json tsconfig.base.json ./
 COPY packages/lit-dev-tools-cjs/package*.json ./packages/lit-dev-tools-cjs/
 COPY packages/lit-dev-tools-esm/package*.json ./packages/lit-dev-tools-esm/
 COPY packages/lit-dev-server/package*.json ./packages/lit-dev-server/
 COPY packages/lit-dev-api/package*.json ./packages/lit-dev-api/
 COPY packages/lit-dev-content/package*.json ./packages/lit-dev-content/
-RUN npm ci && npm run bootstrap
+RUN npm ci
 
 # Tooling code
 COPY packages/lit-dev-tools-cjs/ ./packages/lit-dev-tools-cjs/
 COPY packages/lit-dev-tools-esm/ ./packages/lit-dev-tools-esm/
 COPY packages/lit-dev-server/ ./packages/lit-dev-server/
-RUN npx lerna run build:ts --scope lit-dev-tools-cjs --scope lit-dev-tools-esm --scope lit-dev-server --stream
+RUN npm run build:ts -w packages/lit-dev-tools-cjs -w packages/lit-dev-tools-esm -w packages/lit-dev-server
 
 # Pre-generated API docs data
 COPY packages/lit-dev-api/ ./packages/lit-dev-api/
@@ -59,7 +59,7 @@ RUN echo "LITDEV_ENV=$LITDEV_ENV" >> env \
   && echo "SHORT_SHA=$SHORT_SHA" >> env
 
 # Eleventy build
-RUN npx lerna run prod:build --scope lit-dev-content --stream
+RUN npm run prod:build -w packages/lit-dev-content
 
 # Run the web service on container startup.
 #

README.md

@@ -4,7 +4,7 @@ New site, new repo.
 
 ## Packages
 
-This is a Lerna monorepo.
+This is an npm workspaces monorepo.
 
 - lit-dev-content: Main content of lit.dev
 - lit-dev-server: Production web server for lit.dev
@@ -15,7 +15,7 @@ This is a Lerna monorepo.
 ### Install dependencies
 
 ```sh
-npm i && npm run bootstrap
+npm ci
 ```
 
 ### Build all