From 55afeb7b59fcbe474ac48b1d722c92b217c8238f Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Tue, 29 Sep 2026 16:23:59 -0700
Subject: [PATCH] Use checked-out tools in TypeScript DT runs

The comparison pipeline installs released dtslint packages from
DefinitelyTyped, so local TypeScript 7 package paths use the legacy
loader and every package produces invalid results.

Build and invoke this checkout directly, and expose installation,
builds, and comparison runs as separate Azure steps so failures
identify the affected phase.
---
 .../scripts/compare-typescript-pr-dt.sh       |  16 +++
 .../scripts/run-typescript-pr-dt.sh           | 112 +++++-------------
 .azure-pipelines/typescript-pr-dt.yml         |  84 ++++++++++++-
 3 files changed, 128 insertions(+), 84 deletions(-)
 create mode 100644 .azure-pipelines/scripts/compare-typescript-pr-dt.sh

diff --git a/.azure-pipelines/scripts/compare-typescript-pr-dt.sh b/.azure-pipelines/scripts/compare-typescript-pr-dt.sh
new file mode 100644
index 0000000000..c3a01e46ad
--- /dev/null
+++ b/.azure-pipelines/scripts/compare-typescript-pr-dt.sh
@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+: "${PIPELINE_WORKSPACE:?}"
+
+pr_errors="$PIPELINE_WORKSPACE/pr/errors.txt"
+main_errors="$PIPELINE_WORKSPACE/main/errors.txt"
+
+echo
+echo "=== Errors only in main ==="
+diff --changed-group-format='%<' --unchanged-group-format='' "$main_errors" "$pr_errors" | grep -Ev '^(===|[12]>)' || true
+
+echo
+echo "=== Errors only in branch ==="
+diff --changed-group-format='%>' --unchanged-group-format='' "$main_errors" "$pr_errors" | grep -Ev '^(===|[12]>)' || true
diff --git a/.azure-pipelines/scripts/run-typescript-pr-dt.sh b/.azure-pipelines/scripts/run-typescript-pr-dt.sh
index 09f3a7c623..e17955a561 100644
--- a/.azure-pipelines/scripts/run-typescript-pr-dt.sh
+++ b/.azure-pipelines/scripts/run-typescript-pr-dt.sh
@@ -2,95 +2,45 @@
 
 set -euo pipefail
 
-: "${EXPECTED_BASE_SHA:?}"
-: "${EXPECTED_HEAD_SHA:?}"
-: "${EXPECTED_MERGE_SHA:?}"
 : "${PIPELINE_WORKSPACE:?}"
 : "${SHARD_COUNT:?}"
 : "${SHARD_ID:?}"
 
-typescript_path="$PIPELINE_WORKSPACE/s/TypeScript"
-actual_merge_sha=$(git -C "$typescript_path" rev-parse HEAD)
-actual_base_sha=$(git -C "$typescript_path" rev-parse HEAD^1)
-actual_head_sha=$(git -C "$typescript_path" rev-parse HEAD^2)
-
-verify_sha() {
-    local label=$1
-    local actual=$2
-    local expected=$3
-    if [[ "$actual" != "$expected" ]]; then
-        echo "$label SHA mismatch: expected $expected, got $actual" >&2
+label=${1:?Usage: $0 PR|main}
+case "$label" in
+    PR)
+        root="$PIPELINE_WORKSPACE/pr"
+        failures="$root/prFailures${SHARD_ID}.json"
+        ;;
+    main)
+        root="$PIPELINE_WORKSPACE/main"
+        failures="$root/mainFailures${SHARD_ID}.json"
+        ;;
+    *)
+        echo "Unknown run label: $label" >&2
         exit 1
-    fi
-}
-
-verify_sha merge "$actual_merge_sha" "$EXPECTED_MERGE_SHA"
-verify_sha base "$actual_base_sha" "$EXPECTED_BASE_SHA"
-verify_sha head "$actual_head_sha" "$EXPECTED_HEAD_SHA"
-
-build_typescript() {
-    npm ci
-    npm run build
-    npx hereby build:api
-}
-
-run_dtslint() {
-    local label=$1
-    local root=$2
-    local failures=$3
-    local errors="$root/errors.txt"
+        ;;
+esac
 
-    mkdir -p "$root"
-    echo "$label run: Shard $SHARD_ID of $SHARD_COUNT"
-
-    pushd "$dt_path" >/dev/null
-    set +o pipefail
-    pnpm dtslint-runner \
-        --path . \
-        --localTypeScriptPath "$local_typescript_path" \
-        --selection all \
-        --expectOnly \
-        --shardId "$SHARD_ID" \
-        --shardCount "$SHARD_COUNT" \
-        --writeFailures "$failures" 3>&1 1>&2 2>&3 | tee -a "$errors"
-    set -o pipefail
-    popd >/dev/null
-}
-
-pushd "$typescript_path" >/dev/null
-build_typescript
-popd >/dev/null
+tools_path="$PIPELINE_WORKSPACE/s/DefinitelyTyped-tools"
+typescript_path="$PIPELINE_WORKSPACE/s/TypeScript"
 local_typescript_path="$typescript_path/packages/typescript"
-
 dt_path="$PIPELINE_WORKSPACE/s/DefinitelyTyped"
-pushd "$dt_path" >/dev/null
-npm install --global "$(jq -r '.packageManager' package.json)"
-pnpm install
-popd >/dev/null
+errors="$root/errors.txt"
 
-run_dtslint \
-    PR \
-    "$PIPELINE_WORKSPACE/pr" \
-    "$PIPELINE_WORKSPACE/pr/prFailures${SHARD_ID}.json"
+mkdir -p "$root"
+echo "$label run: Shard $SHARD_ID of $SHARD_COUNT"
+echo "dtslint runner: $tools_path/packages/dtslint-runner/dist/index.js"
 
-git -C "$typescript_path" clean -xdf
-git -C "$typescript_path" switch --detach "$EXPECTED_BASE_SHA"
-pushd "$typescript_path" >/dev/null
-build_typescript
+pushd "$dt_path" >/dev/null
+set +o pipefail
+node "$tools_path/packages/dtslint-runner/dist/index.js" \
+    --path . \
+    --localTypeScriptPath "$local_typescript_path" \
+    --selection all \
+    --expectOnly \
+    --shardId "$SHARD_ID" \
+    --shardCount "$SHARD_COUNT" \
+    --writeFailures "$failures" 3>&1 1>&2 2>&3 | tee -a "$errors"
+set -o pipefail
 popd >/dev/null
-
-run_dtslint \
-    main \
-    "$PIPELINE_WORKSPACE/main" \
-    "$PIPELINE_WORKSPACE/main/mainFailures${SHARD_ID}.json"
-
-pr_errors="$PIPELINE_WORKSPACE/pr/errors.txt"
-main_errors="$PIPELINE_WORKSPACE/main/errors.txt"
-
-echo
-echo "=== Errors only in main ==="
-diff --changed-group-format='%<' --unchanged-group-format='' "$main_errors" "$pr_errors" | grep -Ev '^(===|[12]>)' || true
-
-echo
-echo "=== Errors only in branch ==="
-diff --changed-group-format='%>' --unchanged-group-format='' "$main_errors" "$pr_errors" | grep -Ev '^(===|[12]>)' || true
diff --git a/.azure-pipelines/typescript-pr-dt.yml b/.azure-pipelines/typescript-pr-dt.yml
index 016c20cdb4..0d9a21d14d 100644
--- a/.azure-pipelines/typescript-pr-dt.yml
+++ b/.azure-pipelines/typescript-pr-dt.yml
@@ -88,16 +88,94 @@ jobs:
           version: "1.27"
           goDownloadUrl: https://aka.ms/golang/release/latest
 
-      - bash: bash .azure-pipelines/scripts/run-typescript-pr-dt.sh
-        displayName: Run TypeScript PR DT comparison
-        workingDirectory: $(Pipeline.Workspace)/s/DefinitelyTyped-tools
+      - bash: |
+          set -euo pipefail
+          verify_sha() {
+            local label=$1
+            local actual=$2
+            local expected=$3
+            if [[ "$actual" != "$expected" ]]; then
+              echo "$label SHA mismatch: expected $expected, got $actual" >&2
+              exit 1
+            fi
+          }
+          verify_sha merge "$(git rev-parse HEAD)" "$EXPECTED_MERGE_SHA"
+          verify_sha base "$(git rev-parse HEAD^1)" "$EXPECTED_BASE_SHA"
+          verify_sha head "$(git rev-parse HEAD^2)" "$EXPECTED_HEAD_SHA"
+        displayName: Verify TypeScript checkout
+        workingDirectory: $(Pipeline.Workspace)/s/TypeScript
         env:
           EXPECTED_BASE_SHA: ${{ parameters.expected_base_sha }}
           EXPECTED_HEAD_SHA: ${{ parameters.expected_head_sha }}
           EXPECTED_MERGE_SHA: ${{ parameters.expected_merge_sha }}
+
+      - bash: |
+          set -euo pipefail
+          npm install --global "$(jq -r '.packageManager' package.json)"
+          pnpm install --frozen-lockfile
+        displayName: Install DefinitelyTyped tools dependencies
+        workingDirectory: $(Pipeline.Workspace)/s/DefinitelyTyped-tools
+
+      - bash: pnpm build
+        displayName: Build DefinitelyTyped tools
+        workingDirectory: $(Pipeline.Workspace)/s/DefinitelyTyped-tools
+
+      - bash: npm ci
+        displayName: Install PR TypeScript dependencies
+        workingDirectory: $(Pipeline.Workspace)/s/TypeScript
+
+      - bash: |
+          set -euo pipefail
+          npm run build
+          npx hereby build:api
+        displayName: Build PR TypeScript
+        workingDirectory: $(Pipeline.Workspace)/s/TypeScript
+
+      - bash: |
+          set -euo pipefail
+          npm install --global "$(jq -r '.packageManager' package.json)"
+          pnpm install
+        displayName: Install DefinitelyTyped dependencies
+        workingDirectory: $(Pipeline.Workspace)/s/DefinitelyTyped
+
+      - bash: bash .azure-pipelines/scripts/run-typescript-pr-dt.sh PR
+        displayName: Run dtslint with PR TypeScript
+        workingDirectory: $(Pipeline.Workspace)/s/DefinitelyTyped-tools
+        env:
           SHARD_COUNT: $(System.TotalJobsInPhase)
           SHARD_ID: $(System.JobPositionInPhase)
 
+      - bash: |
+          set -euo pipefail
+          git clean -xdf
+          git switch --detach "$EXPECTED_BASE_SHA"
+        displayName: Prepare base TypeScript checkout
+        workingDirectory: $(Pipeline.Workspace)/s/TypeScript
+        env:
+          EXPECTED_BASE_SHA: ${{ parameters.expected_base_sha }}
+
+      - bash: npm ci
+        displayName: Install base TypeScript dependencies
+        workingDirectory: $(Pipeline.Workspace)/s/TypeScript
+
+      - bash: |
+          set -euo pipefail
+          npm run build
+          npx hereby build:api
+        displayName: Build base TypeScript
+        workingDirectory: $(Pipeline.Workspace)/s/TypeScript
+
+      - bash: bash .azure-pipelines/scripts/run-typescript-pr-dt.sh main
+        displayName: Run dtslint with base TypeScript
+        workingDirectory: $(Pipeline.Workspace)/s/DefinitelyTyped-tools
+        env:
+          SHARD_COUNT: $(System.TotalJobsInPhase)
+          SHARD_ID: $(System.JobPositionInPhase)
+
+      - bash: bash .azure-pipelines/scripts/compare-typescript-pr-dt.sh
+        displayName: Compare dtslint logs
+        workingDirectory: $(Pipeline.Workspace)/s/DefinitelyTyped-tools
+
       - publish: $(Pipeline.Workspace)/pr/prFailures$(System.JobPositionInPhase).json
         displayName: Publish PR failures
         artifact: prFailures$(System.JobPositionInPhase)