From 1031f23fc3aed6760785bf0f8290bd2b2cce41c2 Mon Sep 17 00:00:00 2001
From: Ammar Askar <ammar@ammaraskar.com>
Date: Mon, 28 Dec 2020 13:28:40 -0500
Subject: [PATCH] [workflow] Use MSVC problem matcher for Windows action build
 (GH-18532)

This makes warnings and errors from the compiler very prominent so this should help prevent warnings from sneaking into the code base and catch them in review. See https://discuss.python.org/t/using-github-problem-matchers-to-catch-warnings-early/4254 for more details

You can see a demo of this in action here: https://github.com/ammaraskar/cpython/pull/15/files#diff-9ba2eeca0f254ece0a9df4d7cb68e870

GCC and Sphinx matchers have previously been added in GH-18567 and GH-20325, respectively.
---
 .github/problem-matchers/msvc.json | 19 +++++++++++++++++++
 .github/workflows/build.yml        |  2 ++
 2 files changed, 21 insertions(+)
 create mode 100644 .github/problem-matchers/msvc.json

diff --git a/.github/problem-matchers/msvc.json b/.github/problem-matchers/msvc.json
new file mode 100644
index 00000000000..303a36b1c58
--- /dev/null
+++ b/.github/problem-matchers/msvc.json
@@ -0,0 +1,19 @@
+{
+    "__comment": "Taken from vscode's vs/workbench/contrib/tasks/common/problemMatcher.ts msCompile rule",
+    "problemMatcher": [
+      {
+        "owner": "msvc-problem-matcher",
+        "pattern": [
+          {
+            "regexp": "^(?:\\s+\\d+\\>)?([^\\s].*)\\((\\d+),?(\\d+)?(?:,\\d+,\\d+)?\\)\\s*:\\s+(error|warning|info)\\s+(\\w{1,2}\\d+)\\s*:\\s*(.*)$",
+            "file": 1,
+            "line": 2,
+            "column": 3,
+            "severity": 4,
+            "code": 5,
+            "message": 6
+          }
+        ]
+      }
+    ]
+  }
\ No newline at end of file
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 71c307b6c62..1b865a17b09 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -99,6 +99,8 @@ jobs:
     if: needs.check_source.outputs.run_tests == 'true'
     steps:
     - uses: actions/checkout@v2
+    - name: Register MSVC problem matcher
+      run: echo "::add-matcher::.github/problem-matchers/msvc.json"
     - name: Build CPython
       run: .\PCbuild\build.bat -e -p x64
     - name: Display build info