build external projects for verification testing (#4741)

.github/workflows/build.yml

@@ -0,0 +1,53 @@
+name: Build testing
+on:
+  pull_request:
+  push:
+    branches: [ master ]
+jobs:
+  ufuzz:
+    strategy:
+      fail-fast: false
+      matrix:
+        options: [ '-mb braces', '-mc', '--toplevel -mc passes=10,pure_getters,unsafe' ]
+        script: [ acorn.sh, buble.sh, butternut.sh, rollup-es.sh, rollup-ts.sh, sucrase.sh ]
+        include:
+          - node: '14'
+            script: acorn.sh
+          - node: '14'
+            script: buble.sh
+          - node: '14'
+            script: butternut.sh
+          - node: '8'
+            script: rollup-es.sh
+          - node: '14'
+            script: rollup-ts.sh
+          - node: '14'
+            script: sucrase.sh
+    name: ${{ matrix.script }} ${{ matrix.options }}
+    runs-on: ubuntu-latest
+    env:
+      NODE: ${{ matrix.node }}
+      OPTIONS: ${{ matrix.options }}
+      SCRIPT: ${{ matrix.script }}
+    steps:
+      - uses: actions/checkout@v2
+      - name: Perform uglify, build & test
+        shell: bash
+        run: |
+          git clone --branch v1.6.0 --depth 1 https://github.com/jasongin/nvs.git ~/.nvs
+          while ! timeout 60 bash -c '. ~/.nvs/nvs.sh add $NODE && nvs use $NODE'; do
+            cd ~/.nvs
+            while !(git clean -xdf); do echo "'git clean' failed - retrying..."; done
+            cd -
+          done
+          . ~/.nvs/nvs.sh --version
+          nvs use $NODE
+          node --version
+          npm config set audit false
+          npm config set optional false
+          npm config set save false
+          npm config set strict-ssl false
+          npm config set update-notifier false
+          npm --version
+          while !(npm install); do echo "'npm install' failed - retrying..."; done
+          ./test/release/$SCRIPT $OPTIONS