feat!: Initial v2 commit

* Implemented editorconfig
* Switched to ESM
* Switched to a TypeScript workflow
* Switched to projen for project management
* Major code refactor
* TODO: need tests

.github/workflows/build.yml

@@ -0,0 +1,75 @@
+# ~~ Generated by projen. To modify, edit .projenrc.js and run "npx projen".
+
+name: build
+on:
+  pull_request: {}
+  workflow_dispatch: {}
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+    outputs:
+      self_mutation_happened: ${{ steps.self_mutation.outputs.self_mutation_happened }}
+    env:
+      CI: "true"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+        with:
+          ref: ${{ github.event.pull_request.head.ref }}
+          repository: ${{ github.event.pull_request.head.repo.full_name }}
+      - name: Setup Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: 14.0.0
+      - name: Install dependencies
+        run: npm install
+      - name: build
+        run: npx projen build
+      - name: Find mutations
+        id: self_mutation
+        run: |-
+          git add .
+          git diff --staged --patch --exit-code > .repo.patch || echo "::set-output name=self_mutation_happened::true"
+      - name: Upload patch
+        if: steps.self_mutation.outputs.self_mutation_happened
+        uses: actions/upload-artifact@v2
+        with:
+          name: .repo.patch
+          path: .repo.patch
+      - name: Fail build on mutation
+        if: steps.self_mutation.outputs.self_mutation_happened
+        run: |-
+          echo "::error::Files were changed during build (see build log). If this was triggered from a fork, you will need to update your branch."
+          cat .repo.patch
+          exit 1
+  self-mutation:
+    needs: build
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+    if: always() && needs.build.outputs.self_mutation_happened && !(github.event.pull_request.head.repo.full_name != github.repository)
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+        with:
+          token: ${{ secrets.PROJEN_GITHUB_TOKEN }}
+          ref: ${{ github.event.pull_request.head.ref }}
+          repository: ${{ github.event.pull_request.head.repo.full_name }}
+      - name: Download patch
+        uses: actions/download-artifact@v3
+        with:
+          name: .repo.patch
+          path: ${{ runner.temp }}
+      - name: Apply patch
+        run: '[ -s ${{ runner.temp }}/.repo.patch ] && git apply ${{ runner.temp }}/.repo.patch || echo "Empty patch. Skipping."'
+      - name: Set git identity
+        run: |-
+          git config user.name "github-actions"
+          git config user.email "github-actions@github.com"
+      - name: Push changes
+        run: |2-
+            git add .
+            git commit -s -m "chore: self mutation"
+            git push origin HEAD:${{ github.event.pull_request.head.ref }}