Merged in pfctdayelise/pytest/issue351 (pull request #161)

Fixes issue351: Add ability to specify parametrize ids as a
callable, to generate custom test ids. + tests, docs

Hg branch merge

testing/python/integration.py

@@ -282,5 +282,58 @@ class TestNoselikeTestAttribute:
         call = reprec.getcalls("pytest_collection_modifyitems")[0]
         assert len(call.items) == 1
         assert call.items[0].cls.__name__ == "TC"
-        
 
+
+@pytest.mark.issue351
+class TestParameterize:
+
+    def test_idfn_marker(self, testdir):
+        testdir.makepyfile("""
+            import pytest
+
+            def idfn(param):
+                if param == 0:
+                    return 'spam'
+                elif param == 1:
+                    return 'ham'
+                else:
+                    return None
+
+            @pytest.mark.parametrize('a,b', [(0, 2), (1, 2)], ids=idfn)
+            def test_params(a, b):
+                pass
+        """)
+        res = testdir.runpytest('--collect-only')
+        res.stdout.fnmatch_lines([
+            "*spam-2*",
+            "*ham-2*",
+        ])
+
+    def test_idfn_fixture(self, testdir):
+        testdir.makepyfile("""
+            import pytest
+
+            def idfn(param):
+                if param == 0:
+                    return 'spam'
+                elif param == 1:
+                    return 'ham'
+                else:
+                    return None
+
+            @pytest.fixture(params=[0, 1], ids=idfn)
+            def a(request):
+                return request.param
+
+            @pytest.fixture(params=[1, 2], ids=idfn)
+            def b(request):
+                return request.param
+
+            def test_params(a, b):
+                pass
+        """)
+        res = testdir.runpytest('--collect-only')
+        res.stdout.fnmatch_lines([
+            "*spam-2*",
+            "*ham-2*",
+        ])

testing/python/metafunc.py

@@ -151,6 +151,52 @@ class TestMetafunc:
                           "a6-b6",
                           "a7-b7"]
 
+    @pytest.mark.issue351
+    def test_idmaker_idfn(self):
+        from _pytest.python import idmaker
+        def ids(val):
+            if isinstance(val, Exception):
+                return repr(val)
+
+        result = idmaker(("a", "b"), [(10.0, IndexError()),
+                                      (20, KeyError()),
+                                      ("three", [1, 2, 3]),
+        ], idfn=ids)
+        assert result == ["10.0-IndexError()",
+                          "20-KeyError()",
+                          "three-b2",
+                         ]
+
+    @pytest.mark.issue351
+    def test_idmaker_idfn_unique_names(self):
+        from _pytest.python import idmaker
+        def ids(val):
+            return 'a'
+
+        result = idmaker(("a", "b"), [(10.0, IndexError()),
+                                      (20, KeyError()),
+                                      ("three", [1, 2, 3]),
+        ], idfn=ids)
+        assert result == ["0a-a",
+                          "1a-a",
+                          "2a-a",
+                         ]
+
+    @pytest.mark.issue351
+    def test_idmaker_idfn_exception(self):
+        from _pytest.python import idmaker
+        def ids(val):
+            raise Exception("bad code")
+
+        result = idmaker(("a", "b"), [(10.0, IndexError()),
+                                      (20, KeyError()),
+                                      ("three", [1, 2, 3]),
+        ], idfn=ids)
+        assert result == ["10.0-b0",
+                          "20-b1",
+                          "three-b2",
+                         ]
+
     def test_addcall_and_parametrize(self):
         def func(x, y): pass
         metafunc = self.Metafunc(func)