tests: add basic tests for cluset --completion (cea-hpc#563)

Part of cea-hpc#563.

tests/CLINodesetTest.py

@@ -741,6 +741,17 @@ def test_040_wildcards(self):
         self._nodeset_t(["-s", "other", "--autostep=3", "-f", "*!*[033-099/2]"],
                         None, b"nova[030-032,034-100/2,101-489]\n")
 
+    def test_041_completion(self):
+        """test nodeset --completion"""
+        self._nodeset_t(["--completion"], None,
+                        b"@test:\n@other:\n@bar\n@foo\n@moo\n")
+        self._nodeset_t(["--completion", "node1", "node2"], None,
+                        b"@test:\n@other:\n@bar\n@foo\n@moo\nnode1 node2\n")
+        self._nodeset_t(["-s", "other", "--completion"], None,
+                        b"@other:baz\n@other:norf\n@other:qux\n")
+        self._nodeset_t(["-s", "other", "--completion", "node1", "node2"], None,
+                        b"@other:baz\n@other:norf\n@other:qux\nnode1 node2\n")
+
 
 class CLINodesetGroupResolverTest3(CLINodesetTestBase):
     """Unit test class for testing CLI/Nodeset.py with custom Group Resolver