Add YAML file linter

.github/problem-matchers/README.md

@@ -0,0 +1,19 @@
+# Problem Matchers
+
+GitHub [Problem
+Matchers](https://github.com/actions/toolkit/blob/main/docs/problem-matchers.md)
+are a mechanism that enable workflow steps to scan the outputs of GitHub
+Actions for regex patterns and automatically write annotations in the workflow
+summary page. Using Problem Matchers allows information to be displayed more
+prominently in the GitHub user interface.
+
+This directory contains Problem Matchers used by the GitHub Actions workflows
+in the [`workflows`](./workflows) subdirectory.
+
+The following problem matcher JSON files found in this directory were copied
+from the [Home Assistant](https://github.com/home-assistant/core) project on
+GitHub. The Home Assistant project is licensed under the Apache 2.0 open-source
+license. The version of the files at the time they were copied was 2025.1.2.
+
+- [`pylint.json`](https://github.com/home-assistant/core/blob/dev/.github/workflows/matchers/pylint.json)
+- [`yamllint.json`](https://github.com/home-assistant/core/blob/dev/.github/workflows/matchers/yamllint.json)

.github/problem-matchers/pylint.json

@@ -0,0 +1,32 @@
+{
+  "problemMatcher": [
+    {
+      "owner": "pylint-error",
+      "severity": "error",
+      "pattern": [
+        {
+          "regexp": "^(.+):(\\d+):(\\d+):\\s(([EF]\\d{4}):\\s.+)$",
+          "file": 1,
+          "line": 2,
+          "column": 3,
+          "message": 4,
+          "code": 5
+        }
+      ]
+    },
+    {
+      "owner": "pylint-warning",
+      "severity": "warning",
+      "pattern": [
+        {
+          "regexp": "^(.+):(\\d+):(\\d+):\\s(([CRW]\\d{4}):\\s.+)$",
+          "file": 1,
+          "line": 2,
+          "column": 3,
+          "message": 4,
+          "code": 5
+        }
+      ]
+    }
+  ]
+}

.github/problem-matchers/yamllint.json

@@ -0,0 +1,22 @@
+{
+  "problemMatcher": [
+    {
+      "owner": "yamllint",
+      "pattern": [
+        {
+          "regexp": "^(.*\\.ya?ml)$",
+          "file": 1
+        },
+        {
+          "regexp": "^\\s{2}(\\d+):(\\d+)\\s+(error|warning)\\s+(.*?)\\s+\\((.*)\\)$",
+          "line": 1,
+          "column": 2,
+          "severity": 3,
+          "message": 4,
+          "code": 5,
+          "loop": true
+        }
+      ]
+    }
+  ]
+}

.github/workflows/ci.yml

@@ -8,7 +8,7 @@
 # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 name: Continuous integration checks
-run-name: Continuous integration checks triggered by ${{github.event_name}}
+run-name: CI checks for ${{github.event_name}} by ${{github.actor}}
 
 on:
   pull_request:
@@ -81,6 +81,8 @@ jobs:
     outputs:
       python: ${{steps.filter.outputs.python}}
       python_files: ${{steps.filter.outputs.python_files}}
+      yaml: ${{steps.filter.outputs.yaml}}
+      yaml_files: ${{steps.filter.outputs.yaml_files}}
     steps:
       # When invoked manually, use the given SHA to figure out the change list.
       - if: github.event_name == 'workflow_dispatch'
@@ -121,12 +123,17 @@ jobs:
             python:
               - added|modified:
                   - '**/*.py'
+            yaml:
+              - added|modified:
+                  - '**/*.yaml'
+                  - '**/*.yml'
 
   setup:
     if: needs.changes.outputs.python == 'true'
     name: (Set up Python)
     needs: changes
     runs-on: ubuntu-latest
+    timeout-minutes: 10
     steps:
       - name: Check out a copy of the git repository
         uses: actions/checkout@v4
@@ -155,6 +162,7 @@ jobs:
     name: Python format checks
     needs: [changes, setup]
     runs-on: ubuntu-latest
+    timeout-minutes: 10
     steps:
       - name: Check out a copy of the git repository
         uses: actions/checkout@v4
@@ -180,6 +188,7 @@ jobs:
     name: Python type checks
     needs: [changes, setup]
     runs-on: ubuntu-latest
+    timeout-minutes: 10
     steps:
       - name: Check out a copy of the git repository
         uses: actions/checkout@v4
@@ -203,6 +212,7 @@ jobs:
     name: Python lint checks
     needs: [changes, setup]
     runs-on: ubuntu-latest
+    timeout-minutes: 10
     steps:
       - name: Check out a copy of the git repository
         uses: actions/checkout@v4
@@ -234,6 +244,7 @@ jobs:
     name: (Python pytest matrix)
     needs: [changes, setup]
     runs-on: ${{ matrix.os }}
+    timeout-minutes: 15
     strategy:
       matrix:
         os: [ ubuntu-latest, macos-latest, windows-latest ]
@@ -277,6 +288,7 @@ jobs:
     name: (Python extra pytest matrix)
     needs: [changes, setup]
     runs-on: ${{ matrix.os }}
+    timeout-minutes: 15
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest]
@@ -320,6 +332,7 @@ jobs:
     name: Python compatibility checks
     needs: [changes, setup]
     runs-on: ubuntu-20.04
+    timeout-minutes: 15
     steps:
       - name: Check out a copy of the git repository
         uses: actions/checkout@v4
@@ -343,6 +356,7 @@ jobs:
     name: Python code coverage checks
     needs: [changes, setup]
     runs-on: ubuntu-latest
+    timeout-minutes: 15
     steps:
       - name: Check out a copy of the git repository
         uses: actions/checkout@v4
@@ -361,3 +375,26 @@ jobs:
 
       - name: Run code coverage tests
         run: check/pytest-and-incremental-coverage
+
+  yaml-lint:
+    if: needs.changes.outputs.yaml == 'true'
+    name: YAML lint checks
+    needs: changes
+    runs-on: ubuntu-24.04
+    timeout-minutes: 5
+    env:
+      changed_files: ${{needs.changes.outputs.yaml_files}}
+    steps:
+      - name: Check out a copy of the git repository
+        uses: actions/checkout@v4
+
+      - name: Set up yamllint output problem matcher
+        run: |
+          ls -la
+          echo "::add-matcher::.github/problem-matchers/yamllint.json"
+
+      - name: Run yamllint
+        run: |
+          set -x
+          # shellcheck disable=SC2086
+          yamllint $changed_files

.yamllint.yaml

@@ -0,0 +1,14 @@
+# Summary: yamllint configuration.
+# See https://yamllint.readthedocs.io/ for info about configuration options.
+
+rules:
+  line-length:
+    # YAML files (especially GitHub Actions workflows) tend to end up with
+    # long lines. The default of 80 is pretty limiting, and besides, in Python
+    # code linting, we set line lengths to 100. May as well follow suit here.
+    max: 100
+    # Another common occurrence in YAML files is long URLs. The next two
+    # settings are not specific to URLs, but help. It saves developer time by
+    # not requiring comment directives to disable warnings at every occurrence.
+    allow-non-breakable-words: true
+    allow-non-breakable-inline-mappings: true