improve automatic id generation for parametrized tests

CHANGELOG

@@ -1,6 +1,7 @@
 Changes between 2.2.4 and 2.3.0.dev
 -----------------------------------
 
+- fix issue202 - better automatic names for parametrized test functions
 - fix issue139 - introduce @pytest.fixture which allows direct scoping
   and parametrization of funcarg factories.  Introduce new @pytest.setup
   marker to allow the writing of setup functions which accept funcargs.

_pytest/__init__.py

@@ -1,2 +1,2 @@
 #
-__version__ = '2.3.0.dev31'
+__version__ = '2.3.0.dev32'

_pytest/python.py

@@ -660,8 +660,7 @@ class Metafunc(FuncargnamesCompatAttr):
                                      self.function, arg))
         valtype = indirect and "params" or "funcargs"
         if not ids:
-            idmaker = IDMaker()
+            ids = idmaker(argnames, argvalues)
-            ids = list(map(idmaker, argvalues))
         newcalls = []
         for callspec in self._calls or [CallSpec2(self)]:
             for i, valset in enumerate(argvalues):
@@ -708,18 +707,17 @@ class Metafunc(FuncargnamesCompatAttr):
         cs.setall(funcargs, id, param)
         self._calls.append(cs)
 
-class IDMaker:
+def idmaker(argnames, argvalues):
-    def __init__(self):
+    idlist = []
-        self.counter = 0
+    for valindex, valset in enumerate(argvalues):
-    def __call__(self, valset):
+        this_id = []
-        l = []
+        for nameindex, val in enumerate(valset):
-        for val in valset:
+            if not isinstance(val, (float, int, str)):
-            if not isinstance(val, (int, str)):
+                this_id.append(argnames[nameindex]+str(valindex))
-                val = "."+str(self.counter)
+            else:
-            self.counter += 1
+                this_id.append(str(val))
-            l.append(str(val))
+        idlist.append("-".join(this_id))
-        return "-".join(l)
+    return idlist
-
 
 def showfixtures(config):
     from _pytest.main import wrap_session

setup.py

@@ -24,7 +24,7 @@ def main():
         name='pytest',
         description='py.test: simple powerful testing with Python',
         long_description = long_description,
-        version='2.3.0.dev31',
+        version='2.3.0.dev32',
         url='http://pytest.org',
         license='MIT license',
         platforms=['unix', 'linux', 'osx', 'cygwin', 'win32'],

testing/test_python.py

@@ -992,10 +992,21 @@ class TestMetafunc:
             pass
         metafunc.parametrize("x", [A(), A()])
         metafunc.parametrize("y", list("ab"))
-        assert metafunc._calls[0].id == ".0-a"
+        assert metafunc._calls[0].id == "x0-a"
-        assert metafunc._calls[1].id == ".0-b"
+        assert metafunc._calls[1].id == "x0-b"
-        assert metafunc._calls[2].id == ".1-a"
+        assert metafunc._calls[2].id == "x1-a"
-        assert metafunc._calls[3].id == ".1-b"
+        assert metafunc._calls[3].id == "x1-b"
+
+    def test_idmaker_autoname(self):
+        from _pytest.python import idmaker
+        result = idmaker(("a", "b"), [("string", 1.0),
+                                      ("st-ring", 2.0)])
+        assert result == ["string-1.0", "st-ring-2.0"]
+
+        result = idmaker(("a", "b"), [(object(), 1.0),
+                                      (object(), object())])
+        assert result == ["a0-1.0", "a1-b1"]
+
 
     def test_addcall_and_parametrize(self):
         def func(x, y): pass
@@ -1362,6 +1373,41 @@ class TestMetafuncFunctional:
             "*1 passed*"
         ])
 
+    def test_parametrize_with_ids(self, testdir):
+        testdir.makepyfile("""
+            import pytest
+            def pytest_generate_tests(metafunc):
+                metafunc.parametrize(("a", "b"), [(1,1), (1,2)],
+                                     ids=["basic", "advanced"])
+
+            def test_function(a, b):
+                assert a == b
+        """)
+        result = testdir.runpytest("-v")
+        assert result.ret == 1
+        result.stdout.fnmatch_lines_random([
+            "*test_function*basic*PASSED",
+            "*test_function*advanced*FAILED",
+        ])
+
+    def test_parametrize_without_ids(self, testdir):
+        testdir.makepyfile("""
+            import pytest
+            def pytest_generate_tests(metafunc):
+                metafunc.parametrize(("a", "b"),
+                                     [(1,object()), (1.3,object())])
+
+            def test_function(a, b):
+                assert 1
+        """)
+        result = testdir.runpytest("-v")
+        result.stdout.fnmatch_lines("""
+            *test_function*1-b0*
+            *test_function*1.3-b1*
+        """)
+
+
+
     @pytest.mark.parametrize(("scope", "length"),
                              [("module", 2), ("function", 4)])
     def test_parametrize_scope_overrides(self, testdir, scope, length):
@@ -1985,24 +2031,6 @@ class TestFixtureUsages:
         reprec = testdir.inline_run()
         reprec.assertoutcome(passed=2)
 
-class TestResourceIntegrationFunctional:
-    def test_parametrize_with_ids(self, testdir):
-        testdir.makepyfile("""
-            import pytest
-            def pytest_generate_tests(metafunc):
-                metafunc.parametrize(("a", "b"), [(1,1), (1,2)],
-                                     ids=["basic", "advanced"])
-
-            def test_function(a, b):
-                assert a == b
-        """)
-        result = testdir.runpytest("-v")
-        assert result.ret == 1
-        result.stdout.fnmatch_lines_random([
-            "*test_function*basic*PASSED",
-            "*test_function*advanced*FAILED",
-        ])
-
 class TestFixtureManager:
     def pytest_funcarg__testdir(self, request):
         testdir = request.getfuncargvalue("testdir")