👷 mypy_primer (#824)

Co-authored-by: Copilot <[email protected]>

Author: jorenham

.github/workflows/mypy_primer.yml

@@ -0,0 +1,107 @@
+name: mypy_primer run
+permissions: read-all
+
+on:
+  # only run on pr, since we diff between branches
+  pull_request:
+    paths:
+      - "scipy-stubs/**/*.pyi"
+      - ".github/workflows/mypy_primer.yml"
+      - ".github/workflows/mypy_primer_comment.yml"
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  mypy_primer:
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+
+    strategy:
+      fail-fast: false
+      matrix:
+        # e.g. change this to `[0, 1, 2]` with `--num-shards=3` below
+        shard-index: [0]
+
+    steps:
+      - uses: actions/[email protected]
+        with:
+          path: new
+          fetch-depth: 0
+
+      - uses: astral-sh/[email protected]
+        with:
+          activate-environment: true
+          python-version: "3.13"
+
+      - name: install
+        run: uv pip install git+https://github.com/hauntsaninja/mypy_primer.git
+
+      - name: run
+        shell: bash
+        run: |
+          cd new
+          MYPY_VERSION=$(grep /mypy- uv.lock | sed -n "s/.*\/mypy-\([^;]*\)-py3.*/\1/p")
+
+          echo "new commit"
+          git checkout $GITHUB_SHA
+          git rev-list --format=%s --max-count=1 HEAD
+
+          MERGE_BASE=$(git merge-base $GITHUB_SHA origin/$GITHUB_BASE_REF)
+          git worktree add ../old $MERGE_BASE
+          cd ../old
+
+          echo "old commit"
+          git rev-list --format=%s --max-count=1 HEAD
+
+          echo ""
+          cd ..
+
+          # fail action if exit code isn't zero or one
+          (
+            mypy_primer \
+            --new v${MYPY_VERSION} \
+            --old v${MYPY_VERSION} \
+            --known-dependency-selector scipy-stubs \
+            --old-prepend-path old \
+            --new-prepend-path new \
+            --num-shards 1 \
+            --shard-index ${{ matrix.shard-index }} \
+            --debug \
+            --output concise \
+            | tee diff_${{ matrix.shard-index }}.txt
+          ) || [ $? -eq 1 ]
+
+      - name: save pr number
+        if: ${{ matrix.shard-index == 0 }}
+        run: |
+          echo ${{ github.event.pull_request.number }} | tee pr_number.txt
+
+      - name: upload diff and pr number
+        if: ${{ matrix.shard-index == 0 }}
+        uses: actions/[email protected]
+        with:
+          name: primer_diffs-${{ matrix.shard-index }}
+          path: |
+            diff_${{ matrix.shard-index }}.txt
+            pr_number.txt
+
+      - name: upload diff
+        if: ${{ matrix.shard-index != 0 }}
+        uses: actions/[email protected]
+        with:
+          name: primer_diffs-${{ matrix.shard-index }}
+          path: diff_${{ matrix.shard-index }}.txt
+
+  join_artifacts:
+    needs: [mypy_primer]
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+
+    steps:
+      - uses: actions/upload-artifact/[email protected]
+        with:
+          name: primer_diffs
+          pattern: primer_diffs-*
+          delete-merged: true

.github/workflows/mypy_primer_comment.yml

@@ -0,0 +1,101 @@
+name: mypy_primer comment
+
+permissions:
+  contents: read
+  pull-requests: write
+
+on:
+  workflow_run:
+    workflows: [mypy_primer run]
+    types: [completed]
+
+jobs:
+  comment:
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+
+    steps:
+      - name: download diffs
+        uses: actions/[email protected]
+        with:
+          script: |
+            const fs = require('fs');
+            const artifacts = await github.rest.actions.listWorkflowRunArtifacts({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              run_id: ${{ github.event.workflow_run.id }},
+            });
+            const [matchArtifact] = artifacts.data.artifacts.filter((artifact) => {
+              return artifact.name == 'primer_diffs'
+            });
+
+            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));
+
+      - run: unzip diff.zip
+
+      - name: get pr number
+        id: pr-number
+        uses: actions/[email protected]
+        with:
+          script: |
+            const fs = require('fs');
+            return parseInt(fs.readFileSync('pr_number.txt', {encoding: 'utf8'}))
+
+      - name: hide previous comments
+        uses: int128/[email protected]
+        with:
+          issue-number: ${{ steps.pr-number.outputs.result }}
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - run: cat diff_*.txt | tee fulldiff.txt
+
+      - name: post comment
+        uses: actions/[email protected]
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          script: |
+            const MAX_CHARS = 50000
+            const MAX_CHARS_PER_PROJECT = MAX_CHARS / 3
+
+            const fs = require('fs')
+            let data = fs.readFileSync('fulldiff.txt', {encoding: 'utf8'})
+
+            function maybeTruncate(original, maxLength) {
+              if (original.length <= maxLength) {
+                return original
+              }
+              let truncated = original.substring(0, maxLength)
+              // further, remove last line that might be truncated
+              truncated = truncated.substring(0, truncated.lastIndexOf('\n'))
+              let lines_truncated = original.split('\n').length - truncated.split('\n').length
+              return `${truncated}\n\n... (truncated ${lines_truncated} lines) ...`
+            }
+
+            const projects = data.split('\n\n')
+            // don't let one project dominate
+            data = projects.map(project => maybeTruncate(project, MAX_CHARS_PER_PROJECT)).join('\n\n')
+            // posting comment fails if too long, so truncate
+            data = maybeTruncate(data, MAX_CHARS)
+
+            console.log('mypy_primer diffs:')
+            console.log(data)
+
+            let body
+            if (data.trim()) {
+              body = '[mypy_primer](https://github.com/hauntsaninja/mypy_primer) diffs:\n\n'
+              body += '```diff\n' + data + '```'
+              const prNumber = parseInt(fs.readFileSync('pr_number.txt', {encoding: 'utf8'}))
+              await github.rest.issues.createComment({
+                issue_number: prNumber,
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                body
+              })
+            }