Add comment workflow to show how changes affect stdlib docstrings

Author: AlexWaygood

.github/scripts/typeshed_primer_download_diff.js

@@ -0,0 +1,20 @@
+module.exports = async ({ github, context }) => {
+  const fs = require("fs");
+
+  const artifacts = await github.rest.actions.listWorkflowRunArtifacts({
+    owner: context.repo.owner,
+    repo: context.repo.repo,
+    run_id: context.payload.workflow_run.id,
+  });
+  const [matchArtifact] = artifacts.data.artifacts.filter(
+    (artifact) => artifact.name == "docstring-adder-diff",
+  );
+  const download = await github.rest.actions.downloadArtifact({
+    owner: context.repo.owner,
+    repo: context.repo.repo,
+    artifact_id: matchArtifact.id,
+    archive_format: "zip",
+  });
+
+  fs.writeFileSync("diff.zip", Buffer.from(download.data));
+};

.github/scripts/typeshed_primer_post_comment.js

@@ -0,0 +1,30 @@
+module.exports = async ({ github, context }) => {
+  const fs = require("fs");
+
+  let data = fs.readFileSync("docstring-adder-diff.txt", { encoding: "utf8" });
+  // posting comment fails if too long, so truncate
+  if (data.length > 30000) {
+    let truncated_data = data.substring(0, 30000);
+    let lines_truncated =
+      data.split("\n").length - truncated_data.split("\n").length;
+    data =
+      truncated_data + `\n\n... (truncated ${lines_truncated} lines) ...\n`;
+  }
+
+  const body = data.trim()
+    ? "⚠ Diff showing the effect of this PR on the typeshed stdlib: \n```diff\n" +
+      data +
+      "\n```"
+    : "This change has no effect on the docstrings that would be added to typeshed. 🤖🎉";
+  const issue_number = parseInt(
+    fs.readFileSync("pr_number.txt", { encoding: "utf8" }),
+  );
+  await github.rest.issues.createComment({
+    issue_number,
+    owner: context.repo.owner,
+    repo: context.repo.repo,
+    body,
+  });
+
+  return issue_number;
+};

.github/workflows/typeshed_primer.yml

@@ -0,0 +1,64 @@
+name: typeshed_primer
+
+on:
+  pull_request:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+env:
+  FORCE_COLOR: 1
+  CLICOLOR_FORCE: 1 # recognized by uv
+
+jobs:
+  typeshed_primer:
+    timeout-minutes: 5
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout docstring-adder on target branch
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ github.base_ref }}
+          path: old_codemod
+      - name: Checkout docstring-adder on PR branch
+        uses: actions/checkout@v4
+        with:
+          path: new_codemod
+      - name: Checkout typeshed
+        uses: actions/checkout@v4
+        with:
+          repository: python/typeshed
+          path: typeshed
+      - uses: astral-sh/setup-uv@v6
+      - name: Setup git
+        run: |
+          git config --global user.name stubdefaulter
+          git config --global user.email ''
+      - name: Codemod typeshed using target branch
+        run: |
+          uvx --python=3.13 --from=./old_codemod add-docstrings --stdlib-path ./typeshed/stdlib
+          uvx --python=3.9 --from=./old_codemod add-docstrings --stdlib-path ./typeshed/stdlib
+          uvx --directory=typeshed black stdlib|| true
+          git -C typeshed commit -a -m "With old stubdefaulter"
+      - name: Codemod typeshed using PR branch
+        run: |
+          git -C typeshed checkout HEAD~1 -- stdlib
+          git -C typeshed restore --staged stdlib
+          uvx --python=3.13 --from=./new_codemod add-docstrings --stdlib-path ./typeshed/stdlib
+          uvx --python=3.9 --from=./new_codemod add-docstrings --stdlib-path ./typeshed/stdlib
+          uvx --directory=typeshed black stdlib || true
+      - name: Get the diff between the two docstring-adder runs
+        run: git -C typeshed diff | tee docstring-adder-diff.txt
+      - name: Save PR number
+        run: echo ${{ github.event.pull_request.number }} | tee pr_number.txt
+      - name: Upload diff and PR number
+        uses: actions/upload-artifact@v4
+        with:
+          name: docstring-adder-diff
+          path: |
+            docstring-adder-diff.txt
+            pr_number.txt

.github/workflows/typeshed_primer_comment.yml

@@ -0,0 +1,42 @@
+name: Post typeshed_primer comment
+
+on:
+  workflow_run:
+    workflows:
+      - typeshed_primer
+    types:
+      - completed
+
+permissions:
+  contents: read
+  pull-requests: write
+
+env:
+  FORCE_COLOR: 1
+  CLICOLOR_FORCE: 1 # recognized by uv
+
+jobs:
+  comment:
+    name: Comment PR from typeshed_primer
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Download diff
+        uses: actions/github-script@v7
+        with:
+          script: await require('.github/scripts/typeshed_primer_download_diff.js')({github, context})
+      - run: unzip diff.zip
+      - name: Post comment
+        id: post-comment
+        uses: actions/github-script@v7
+        with:
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          script: return await require('.github/scripts/typeshed_primer_post_comment.js')({github, context})
+      - name: Hide old comments
+        # v0.4.0
+        uses: kanga333/comment-hider@c12bb20b48aeb8fc098e35967de8d4f8018fffdf
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          leave_visible: 1
+          issue_number: ${{ steps.post-comment.outputs.result }}