Initialize TypeScript (rstudio#3296)

.Rbuildignore

@@ -12,7 +12,7 @@
 ^\.travis\.yml$
 ^staticdocs$
 ^tools$
-^srcjs$
+^srcts$
 ^CONTRIBUTING.md$
 ^cran-comments.md$
 ^.*\.o$

.github/workflows/rituals.yaml

@@ -20,7 +20,7 @@ jobs:
       fail-fast: false
       matrix:
         config:
-        - { os: ubuntu-16.04, r: '4.0', rspm: "https://packagemanager.rstudio.com/all/__linux__/xenial/latest"}
+        - { os: ubuntu-16.04, r: '4.0', node: "14.x", rspm: "https://packagemanager.rstudio.com/all/__linux__/xenial/latest"}
 
     env:
       R_REMOTES_NO_ERRORS_FROM_WARNINGS: true
@@ -110,7 +110,7 @@ jobs:
 
       - uses: actions/setup-node@v1
         with:
-          node-version: '12.x'
+          node-version: ${{ matrix.config.node }}
       # https://github.com/actions/cache/blame/ccf96194800dbb7b7094edcd5a7cf3ec3c270f10/examples.md#L185-L200
       - name: Get yarn cache directory path
         id: yarn-cache-dir-path
@@ -120,18 +120,18 @@ jobs:
         id: yarn-cache # use this to check for `cache-hit` (`steps.yarn-cache.outputs.cache-hit != 'true'`)
         with:
           path: ${{ steps.yarn-cache-dir-path.outputs.dir }}
-          key: ${{ matrix.config.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
+          key: ${{ matrix.config.os }}-${{ matrix.config.node }}-yarn-${{ hashFiles('**/yarn.lock') }}
           restore-keys: |
-            ${{ matrix.config.os }}-yarn-
+            ${{ matrix.config.os }}-${{ matrix.config.node }}-yarn-
       - name: Build JS
         run: |
-          cd tools
-          yarn install --frozen-lockfile
-          yarn build
-          git add ../inst
-          git commit -m 'yarn build (GitHub Actions)' || echo "No yarn changes to commit"
+          cd srcts
+          tree src
+          yarn install --immutable && yarn build
+          git add ./src && git commit -m 'yarn lint (GitHub Actions)' || echo "No yarn lint changes to commit"
+          git add ../inst && git commit -m 'yarn build (GitHub Actions)' || echo "No yarn build changes to commit"
 
-      - name: Check node build
+      - name: Check JS build is latest
         run: |
           ./tools/checkJSCurrent.sh
 
@@ -145,3 +145,9 @@ jobs:
         if: github.event_name == 'push'
         run: |
           git push https://${{github.actor}}:${{secrets.GITHUB_TOKEN}}@github.com/${{github.repository}}.git HEAD:${{ github.ref }} || echo "No changes to push"
+
+      # Execute after pushing, as no updated files will be produced
+      - name: Test TypeScript code
+        run: |
+          cd srcts
+          yarn test

NEWS.md

@@ -9,6 +9,8 @@ shiny 1.6.0.9000
 
 ### Minor new features and improvements
 
+* Shiny's core JavaScript code was converted to TypeScript. For the latest developement information, please see the [README.md in `./srcts`](https://github.com/rstudio/shiny/tree/master/srcts). (#3296)
+
 * Switched from `digest::digest()` to `rlang::hash()` for hashing. (#3264)
 
 * Switched from internal `Stack` class to `fastmap::faststack()`, and used `fastmap::fastqueue()`. (#3176)