1 files changed, 45 insertions, 0 deletions
diff --git a/lib/ansiblelint/rules/CommandHasChangesCheckRule.py b/lib/ansiblelint/rules/CommandHasChangesCheckRule.py
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+++ b/lib/ansiblelint/rules/CommandHasChangesCheckRule.py
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+# Copyright (c) 2016 Will Thames <will@thames.id.au>
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+from ansiblelint.rules import AnsibleLintRule
+
+
+class CommandHasChangesCheckRule(AnsibleLintRule):
+    id = '301'
+    shortdesc = 'Commands should not change things if nothing needs doing'
+    description = (
+        'Commands should either read information (and thus set '
+        '``changed_when``) or not do something if it has already been '
+        'done (using creates/removes) or only do it if another '
+        'check has a particular result (``when``)'
+    )
+    severity = 'HIGH'
+    tags = ['command-shell', 'idempotency', 'ANSIBLE0012']
+    version_added = 'historic'
+
+    _commands = ['command', 'shell', 'raw']
+
+    def matchtask(self, file, task):
+        if task["__ansible_action_type__"] == 'task':
+            if task["action"]["__ansible_module__"] in self._commands:
+                return 'changed_when' not in task and \
+                    'when' not in task and \
+                    'creates' not in task['action'] and \
+                    'removes' not in task['action']