strip Jinja constructs before running yamllint

Many YAML files in this project contain Jinja2 templating ({{% %}},
{{{ }}}, {{# #}}) which causes yamllint to report false syntax errors.

Add a helper script (utils/strip_jinja_for_yamllint.py) that removes
Jinja constructs while preserving line numbers, and update the CI
workflow to use it for files that contain Jinja. Files without Jinja
are linted directly as before. Warnings are reported but do not fail
the job.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: vojtapolasek

.github/workflows/ci_lint.yml

@@ -35,7 +35,33 @@ jobs:
 
       - name: Run yamllint on files modified by the PR
         run: |
+          exit_code=0
           for file in $(cat filenames.txt); do
+            if [[ ! -f "$file" ]]; then
+              continue
+            fi
             echo "Running yamllint on $file..."
-            yamllint -c .yamllint "$file"
+            if grep -qP '\{\{[%{#]' "$file"; then
+              # File contains Jinja2 constructs — strip them before linting.
+              # yamllint -s exits: 0 = clean, 1 = errors, 2 = warnings only.
+              output=$(python3 utils/strip_jinja_for_yamllint.py "$file" \
+                       | yamllint -s -c .yamllint - 2>&1)
+              rc=$?
+              # Show all output (warnings and errors), replacing "stdin"
+              # with the actual filename since yamllint reads from a pipe.
+              if [ -n "$output" ]; then
+                echo "$output" | sed "s|^stdin|$file|"
+              fi
+              # Fail only on errors (exit code 1), not warnings (exit code 2).
+              if [ "$rc" -eq 1 ]; then
+                exit_code=1
+              fi
+            else
+              yamllint -s -c .yamllint "$file"
+              rc=$?
+              if [ "$rc" -eq 1 ]; then
+                exit_code=1
+              fi
+            fi
           done
+          exit $exit_code

utils/strip_jinja_for_yamllint.py

@@ -0,0 +1,78 @@
+#!/usr/bin/env python3
+"""Strip Jinja2 constructs from YAML files to make them yamllint-safe.
+
+This project uses Jinja2 templating ({{% %}}, {{{ }}}, {{# #}}) inside YAML
+files.  yamllint cannot parse these constructs, so this script removes them
+while preserving line numbers (replaced regions become blank lines) so that
+yamllint error messages still point to the correct source lines.
+
+Usage:
+    python3 utils/strip_jinja_for_yamllint.py FILE
+
+The cleaned content is written to stdout.
+"""
+
+import re
+import sys
+
+
+def _replace_with_blanks(match):
+    """Replace a match with the same number of newlines to preserve line numbers."""
+    return "\n" * match.group(0).count("\n")
+
+
+def strip_jinja(content):
+    # 1. Remove whole-line Jinja block tags: {{% ... %}} on their own line(s).
+    #    Match the entire line (including leading whitespace) to avoid leaving
+    #    trailing spaces behind.
+    content = re.sub(
+        r"^[ \t]*\{\{%.*?%\}\}[ \t]*$",
+        _replace_with_blanks,
+        content,
+        flags=re.MULTILINE | re.DOTALL,
+    )
+    # Remove any remaining inline block tags (rare).
+    content = re.sub(r"\{\{%.*?%\}\}", _replace_with_blanks, content, flags=re.DOTALL)
+
+    # 2. Remove whole-line Jinja comments: {{# ... #}}
+    content = re.sub(
+        r"^[ \t]*\{\{#.*?#\}\}[ \t]*$",
+        _replace_with_blanks,
+        content,
+        flags=re.MULTILINE | re.DOTALL,
+    )
+    # Remove any remaining inline comments.
+    content = re.sub(r"\{\{#.*?#\}\}", "", content, flags=re.DOTALL)
+
+    # 3a. Standalone Jinja expressions occupying entire lines — these typically
+    #     expand to top-level YAML keys (e.g. ocil/ocil_clause macros) or
+    #     Ansible tasks, so replacing them with a placeholder string would
+    #     produce invalid YAML.  Replace with a YAML-safe comment placeholder
+    #     to avoid trailing whitespace on otherwise blank lines.
+    content = re.sub(
+        r"^([ \t]*)\{\{\{.*?\}\}\}[ \t]*$",
+        lambda m: m.group(1) + "# jinja" + "\n" * (m.group(0).count("\n") - 1)
+        if m.group(0).count("\n") > 0
+        else m.group(1) + "# jinja",
+        content,
+        flags=re.MULTILINE | re.DOTALL,
+    )
+
+    # 3b. Inline Jinja expressions embedded inside a YAML value — replace
+    #     with a short placeholder so the surrounding YAML stays valid.
+    content = re.sub(r"\{\{\{.*?\}\}\}", "JINJA_EXPRESSION", content)
+
+    return content
+
+
+def main():
+    if len(sys.argv) != 2:
+        print(f"Usage: {sys.argv[0]} FILE", file=sys.stderr)
+        sys.exit(2)
+
+    with open(sys.argv[1]) as f:
+        sys.stdout.write(strip_jinja(f.read()))
+
+
+if __name__ == "__main__":
+    main()