From f15106cdec44036180019b0db26f70fe071b1b9b Mon Sep 17 00:00:00 2001
From: jrfnl <jrfnl@users.noreply.github.com>
Date: Fri, 10 Nov 2023 20:07:22 +0100
Subject: [PATCH] GH Actions: add Yamllint to `validate` workflow

... to loosely safeguard valid and consistent yaml files and prevent issues like seen in PR 68.

Includes adding a configuration file which loosens up the `default` ruleset to a degree I'm comfortable with.

Ref: https://yamllint.readthedocs.io/
---
 .gitattributes                 |  1 +
 .github/workflows/validate.yml | 15 +++++++++++++++
 .yamllint.yml                  | 23 +++++++++++++++++++++++
 3 files changed, 39 insertions(+)
 create mode 100644 .yamllint.yml

diff --git a/.gitattributes b/.gitattributes
index 3fd67cf09b..ca33149203 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -12,6 +12,7 @@ tests/                  export-ignore
 .cspell.json            export-ignore
 .gitattributes          export-ignore
 .gitignore              export-ignore
+.yamllint.yml           export-ignore
 phpcs.xml.dist          export-ignore
 phpstan.neon.dist       export-ignore
 phpunit.xml.dist        export-ignore
diff --git a/.github/workflows/validate.yml b/.github/workflows/validate.yml
index 2f86c5da4f..15e086be9f 100644
--- a/.github/workflows/validate.yml
+++ b/.github/workflows/validate.yml
@@ -62,3 +62,18 @@ jobs:
           diff -B ./src/Standards/PSR12/ruleset.xml <(xmllint --format "./src/Standards/PSR12/ruleset.xml")
           diff -B ./src/Standards/Squiz/ruleset.xml <(xmllint --format "./src/Standards/Squiz/ruleset.xml")
           diff -B ./src/Standards/Zend/ruleset.xml <(xmllint --format "./src/Standards/Zend/ruleset.xml")
+
+  yamllint:
+    name: 'Lint Yaml'
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Run Yamllint on all yaml files in repo
+        run: yamllint . --format colored --strict
+
+      - name: Pipe Yamllint results on to GH for inline display
+        if: ${{ failure() }}
+        run: yamllint . --format github --strict
diff --git a/.yamllint.yml b/.yamllint.yml
new file mode 100644
index 0000000000..76ea3dce5f
--- /dev/null
+++ b/.yamllint.yml
@@ -0,0 +1,23 @@
+# Details on the default config:
+# https://yamllint.readthedocs.io/en/stable/configuration.html#default-configuration
+extends: default
+
+yaml-files:
+  - '*.yaml'
+  - '*.yml'
+  - '.yamllint'
+  - 'phpstan.neon'
+
+# Rule documentation: https://yamllint.readthedocs.io/en/stable/rules.html
+rules:
+  colons:
+    max-spaces-after: -1  # Disabled to allow aligning of values.
+  comments:
+    min-spaces-from-content: 1
+  comments-indentation: {}
+  document-start:
+    present: false
+  line-length:
+    max: 150
+  truthy:
+    allowed-values: ["true", "false", "on", "off"]