feat: add rule CheckWhenFormat

ansiblelater/rules/CheckWhenFormat.py

@@ -0,0 +1,29 @@
+from ansiblelater.standard import StandardBase
+
+
+class CheckWhenFormat(StandardBase):
+
+    sid = "ANSIBLE0022"
+    description = "Don't use Jinja2 in when"
+    helptext = (
+        "`when` is a raw Jinja2 expression, redundant {{ }} "
+        "should be removed from variable(s)"
+    )
+    version = "0.2"
+    types = ["playbook", "task", "handler"]
+
+    def check(self, candidate, settings):
+        tasks, errors = self.get_normalized_tasks(candidate, settings)
+
+        if not errors:
+            for task in tasks:
+                if 'when' in task and not self._is_valid(task['when']):
+                    errors.append(self.Error(task["__line__"], self.helptext))
+
+        return self.Result(candidate.path, errors)
+
+    @staticmethod
+    def _is_valid(when):
+        if not isinstance(when, str):
+            return True
+        return when.find('{{') == -1 and when.find('}}') == -1

docs/content/included_rules/_index.md

@@ -29,10 +29,11 @@ Reviews are nothing without some rules or standards against which to review. ans
 | CheckCompareToEmptyString     | ANSIBLE0012 | Don't compare to "" - use `when: var` or `when: not var`.         |                                                                      |
 | CheckCompareToLiteralBool     | ANSIBLE0013 | Don't compare to True/False - use `when: var` or `when: not var`. |                                                                      |
 | CheckLiteralBoolFormat        | ANSIBLE0014 | Literal bools should be written as `True/False` or `yes/no`.      | forbidden values are `true false TRUE FALSE Yes No YES NO`           |
-| CheckBecomeUser               | ANSIBLE0015 | `become` should be always used combined with `become_user`.       |                                                                      |
+| CheckBecomeUser               | ANSIBLE0015 | Become should be combined with become_user.                       |                                                                      |
 | CheckFilterSeparation         | ANSIBLE0016 | Jinja2 filters should be separated with spaces.                   |                                                                      |
 | CheckCommandInsteadOfArgument | ANSIBLE0017 | Commands should not be used in place of module arguments.         |                                                                      |
 | CheckFilePermissionMissing    | ANSIBLE0018 | File permissions unset or incorrect.                              |                                                                      |
 | CheckFilePermissionOctal      | ANSIBLE0019 | Octal file permissions must contain leading zero or be a string.  |                                                                      |
 | CheckGitHasVersion            | ANSIBLE0020 | Git checkouts should use explicit version.                        |                                                                      |
 | CheckMetaChangeFromDefault    | ANSIBLE0021 | Roles meta/main.yml default values should be changed.             |                                                                      |
+| CheckWhenFormat               | ANSIBLE0022 | Don't use Jinja2 in `when`.                                       |                                                                      |