chore: import upstream snapshot with attribution

.github/workflows/regression-tests.yml

@@ -0,0 +1,283 @@
+name: Regression Tests
+
+on:
+  pull_request:
+    types: [opened, synchronize, reopened]
+
+env:
+  REGRESSION_TESTING: true
+
+permissions:
+  contents: read
+  pull-requests: write
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number }}
+  cancel-in-progress: true
+
+jobs:
+  resolve-main:
+    name: Resolve main
+    runs-on: ubuntu-latest
+    outputs:
+      main_sha: ${{ steps.resolve.outputs.main_sha }}
+
+    steps:
+      - name: Checkout DoltgreSQL
+        uses: actions/checkout@v6
+        with:
+          ref: main
+
+      - name: Resolve main SHA
+        id: resolve
+        run: echo "main_sha=$(git rev-parse HEAD)" >> "$GITHUB_OUTPUT"
+
+  pr-regression:
+    name: PR regression
+    runs-on: ubuntu-latest
+    needs: resolve-main
+
+    steps:
+      - name: Checkout DoltgreSQL
+        uses: actions/checkout@v6
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+          fetch-depth: 0
+
+      - name: Setup Git User
+        uses: fregante/setup-git-user@v2
+
+      - name: Merge base into PR
+        run: |
+          git fetch origin ${{ needs.resolve-main.outputs.main_sha }}
+          git merge ${{ needs.resolve-main.outputs.main_sha }} --no-commit --no-ff
+
+      - name: Install Go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: go.mod
+          cache: true
+
+      - name: Test PR branch
+        continue-on-error: true
+        run: |
+          ./postgres/parser/build.sh
+          cd testing/go/regression
+          mkdir -p out
+          {
+            echo "pr_head=${{ github.event.pull_request.head.sha }}"
+            echo "main_head=${{ needs.resolve-main.outputs.main_sha }}"
+            echo "merge_base=$(git merge-base HEAD ${{ needs.resolve-main.outputs.main_sha }})"
+            git status --short --branch
+            git diff --cached --stat
+            go version
+            go env
+            go list -m github.com/dolthub/dolt/go github.com/dolthub/go-mysql-server
+          } > out/pr-metadata.txt
+          cd tool
+          set +e
+          go test --timeout=90m ./... --count=1 2>&1 | tee ../out/pr-go-test.log
+          test_status=${PIPESTATUS[0]}
+          set -e
+          if [ -f ../out/results.trackers ]; then
+            cp ../out/results.trackers ../out/results2.trackers
+          fi
+          exit "$test_status"
+
+      - name: Upload PR regression artifacts
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: regression-pr-${{ github.run_id }}-${{ github.run_attempt }}
+          path: |
+            testing/go/regression/out/results2.trackers
+            testing/go/regression/out/pr-go-test.log
+            testing/go/regression/out/pr-metadata.txt
+          if-no-files-found: warn
+          retention-days: 14
+          compression-level: 0
+
+  main-regression:
+    name: Main regression
+    runs-on: ubuntu-latest
+    needs: resolve-main
+
+    steps:
+      - name: Checkout DoltgreSQL
+        uses: actions/checkout@v6
+        with:
+          ref: ${{ needs.resolve-main.outputs.main_sha }}
+
+      - name: Install Go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: go.mod
+          cache: true
+
+      - name: Test main branch
+        continue-on-error: true
+        run: |
+          ./postgres/parser/build.sh
+          cd testing/go/regression
+          mkdir -p out
+          {
+            echo "main_head=${{ needs.resolve-main.outputs.main_sha }}"
+            git status --short --branch
+            go version
+            go env
+            go list -m github.com/dolthub/dolt/go github.com/dolthub/go-mysql-server
+          } > out/main-metadata.txt
+          cd tool
+          set +e
+          go test --timeout=90m ./... --count=1 2>&1 | tee ../out/main-go-test.log
+          test_status=${PIPESTATUS[0]}
+          set -e
+          if [ -f ../out/results.trackers ]; then
+            cp ../out/results.trackers ../out/results1.trackers
+          fi
+          exit "$test_status"
+
+      - name: Upload main regression artifacts
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: regression-main-${{ github.run_id }}-${{ github.run_attempt }}
+          path: |
+            testing/go/regression/out/results1.trackers
+            testing/go/regression/out/main-go-test.log
+            testing/go/regression/out/main-metadata.txt
+          if-no-files-found: warn
+          retention-days: 14
+          compression-level: 0
+
+  regression-tests:
+    runs-on: ubuntu-latest
+    needs:
+      - resolve-main
+      - pr-regression
+      - main-regression
+    if: always() && needs.pr-regression.result != 'cancelled' && needs.main-regression.result != 'cancelled'
+
+    steps:
+      - name: Checkout DoltgreSQL
+        uses: actions/checkout@v6
+        with:
+          ref: ${{ needs.resolve-main.outputs.main_sha }}
+
+      - name: Install Go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: go.mod
+          cache: true
+
+      - name: Download PR regression artifacts
+        uses: actions/download-artifact@v4
+        continue-on-error: true
+        with:
+          name: regression-pr-${{ github.run_id }}-${{ github.run_attempt }}
+          path: testing/go/regression/out
+
+      - name: Download main regression artifacts
+        uses: actions/download-artifact@v4
+        continue-on-error: true
+        with:
+          name: regression-main-${{ github.run_id }}-${{ github.run_attempt }}
+          path: testing/go/regression/out
+
+      - name: Check result trackers
+        id: check_trackers
+        run: |
+          cd testing/go/regression/out
+          if [[ -f "results1.trackers" && -f "results2.trackers" ]]; then
+            echo "trackers_exist=true" >> $GITHUB_OUTPUT
+            echo "trackers exist"
+          else
+            echo "trackers_exist=false" >> $GITHUB_OUTPUT
+            echo "One of the branches could not successfully complete their tests."
+            echo "Please review uploaded regression artifacts for errors, which must be fixed."
+            exit 1
+          fi
+
+      - name: Build Regression Test Results Comment
+        id: build_results
+        if: steps.check_trackers.outputs.trackers_exist == 'true'
+        run: |
+          ./postgres/parser/build.sh
+          cd testing/go/regression/tool
+          # Pass via file, not $GITHUB_OUTPUT: large output through env trips ARG_MAX in github-script.
+          go run . results1.trackers results2.trackers > "$RUNNER_TEMP/regression-comment.md"
+          cp "$RUNNER_TEMP/regression-comment.md" ../out/regression-comment.md
+          cat "$RUNNER_TEMP/regression-comment.md"
+          if [ -s "$RUNNER_TEMP/regression-comment.md" ]; then
+            echo "has_output=true" >> "$GITHUB_OUTPUT"
+          else
+            echo "has_output=false" >> "$GITHUB_OUTPUT"
+          fi
+
+      - name: Upload comparison artifacts
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: regression-comparison-${{ github.run_id }}-${{ github.run_attempt }}
+          path: testing/go/regression/out/regression-comment.md
+          if-no-files-found: warn
+          retention-days: 14
+          compression-level: 0
+
+      - name: Is PR From Fork
+        id: from_fork
+        run: |
+          if [ "${{ github.event.pull_request.head.repo.full_name }}" != "${{ github.repository }}" ]; then
+            echo "This is running from a fork, skipping commenting"
+            echo "fork=true" >> $GITHUB_OUTPUT
+          else
+            echo "This is not running from a fork"
+            echo "fork=false" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Post Comment
+        if: steps.from_fork.outputs.fork == 'false' && steps.build_results.outputs.has_output == 'true'
+        uses: actions/github-script@v7
+        env:
+          COMMENT_PATH: ${{ runner.temp }}/regression-comment.md
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          script: |
+            const fs = require('fs')
+            const commentMarker = '<!-- go-run-output -->'
+            // GitHub caps comment bodies at 65536 chars.
+            const MAX_BODY = 65000
+            let output = fs.readFileSync(process.env.COMMENT_PATH, 'utf8')
+            let body = `${commentMarker}\n${output}`
+            if (body.length > MAX_BODY) {
+              const notice = '\n\n_Output truncated; see workflow logs for the full report._'
+              body = body.slice(0, MAX_BODY - notice.length) + notice
+            }
+
+            // List comments on the PR
+            const { data: comments } = await github.rest.issues.listComments({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+            })
+
+            // Check if a comment already exists
+            const comment = comments.find(comment => comment.body.includes(commentMarker))
+
+            if (comment) {
+              // Update the existing comment
+              await github.rest.issues.updateComment({
+                comment_id: comment.id,
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                body: body
+              })
+            } else {
+              // Create a new comment
+              await github.rest.issues.createComment({
+                issue_number: context.issue.number,
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                body: body
+              })
+            }