add --override-ini option to overrides ini values

Signed-off-by: Ted Xiao <xiao.xj@gmail.com>

AUTHORS

@@ -98,6 +98,7 @@ Ryan Wooden
 Samuele Pedroni
 Stephan Obermann
 Tareq Alayan
+Ted Xiao
 Simon Gomizelj
 Stefano Taschini
 Stefan Farmbauer

CHANGELOG.rst

@@ -47,6 +47,13 @@
   `#1629`_. Thanks `@obestwalter`_ and `@davehunt`_ for the complete PR
   (`#1633`_)
 
+* New cli flag ``--override-ini`` or ``-o`` that overrides ini values from the
+command line so that one can do e.g. "-o xfail_strict=True". This is useful for
+specifying options for which there is no separate command-line flag, a complete
+ini-options can be showed by py.test --help
+Thanks `@blueyed`_ and `@fengxx`_ for the PR
+
+
 **Changes**
 
 * Fixtures marked with ``@pytest.fixture`` can now use ``yield`` statements exactly like

_pytest/config.py

@@ -1003,14 +1003,16 @@ def _getini(self, name):
             description, type, default = self._parser._inidict[name]
         except KeyError:
             raise ValueError("unknown configuration value: %r" %(name,))
-        try:
-            value = self.inicfg[name]
-        except KeyError:
-            if default is not None:
-                return default
-            if type is None:
-                return ''
-            return []
+        value = self._get_override_ini_value(name)
+        if value is None:
+            try:
+                value = self.inicfg[name]
+            except KeyError:
+                if default is not None:
+                    return default
+                if type is None:
+                    return ''
+                return []
         if type == "pathlist":
             dp = py.path.local(self.inicfg.config.path).dirpath()
             l = []
@@ -1041,6 +1043,15 @@ def _getconftest_pathlist(self, name, path):
             l.append(relroot)
         return l
 
+    def _get_override_ini_value(self, name):
+        value = None
+        if self.getoption("override_ini", None):
+            for ini_config in self.option.override_ini:
+                (key, user_ini_value) = ini_config.split("=", 2)
+                if key == name:
+                    return user_ini_value
+        return value
+
     def getoption(self, name, default=notset, skip=False):
         """ return command line option value.
 

_pytest/helpconfig.py

@@ -20,6 +20,12 @@ def pytest_addoption(parser):
     group.addoption('--debug',
                action="store_true", dest="debug", default=False,
                help="store internal tracing debug information in 'pytestdebug.log'.")
+    # support for "--overwrite-ini ININAME=INIVALUE" to overrides ini values from the command line
+    # so that one can do e.g. "-o xfail_strict=True". This is useful for specifying options for which
+    # there is no separate command-line flag, you can find ini-options by py.test --help
+    group._addoption('-o', '--override-ini',
+                    nargs='*', dest="override_ini",
+                    help="overrides ini values which do not have a separate command-line flag")
 
 
 @pytest.hookimpl(hookwrapper=True)

testing/test_config.py

@@ -583,3 +583,60 @@ def test_with_specific_inifile(self, tmpdir):
         inifile = tmpdir.ensure("pytest.ini")
         rootdir, inifile, inicfg = determine_setup(inifile, [tmpdir])
         assert rootdir == tmpdir
+
+class TestOverrideIniArgs:
+    """ test --override-ini """
+    @pytest.mark.parametrize("name", "setup.cfg tox.ini pytest.ini".split())
+    def test_override_ini_names(self, testdir, name):
+        testdir.tmpdir.join(name).write(py.std.textwrap.dedent("""
+            [pytest]
+            custom = 1.0
+        """))
+        testdir.makeconftest("""
+            def pytest_addoption(parser):
+                parser.addini("custom", "")
+        """)
+        testdir.makepyfile("""
+            import pytest
+            def test_pass():
+                ini_val = pytest.config.getini("custom")
+                print('\\ncustom_option:%s\\n' % ini_val)
+        """)
+
+        result = testdir.runpytest("--override-ini", "custom=2.0", "-s")
+        assert result.ret == 0
+        result.stdout.fnmatch_lines([
+            "custom_option:2.0"
+        ])
+
+        result = testdir.runpytest("--override-ini", "custom=2.0",
+                                   "--override-ini=custom=3.0", "-s")
+        assert result.ret == 0
+        result.stdout.fnmatch_lines([
+            "custom_option:3.0"
+        ])
+
+
+    def test_override_ini_pathlist(self, testdir):
+        testdir.makeconftest("""
+                def pytest_addoption(parser):
+                    parser.addini("paths", "my new ini value", type="pathlist")
+        """)
+        testdir.makeini("""
+                [pytest]
+                paths=blah.py
+        """)
+        testdir.makepyfile("""
+                import pytest
+                import py.path
+                def test_pathlist():
+                    config_paths = pytest.config.getini("paths")
+                    print(config_paths)
+                    for cpf in config_paths:
+                        print('\\nuser_path:%s' % cpf.basename)
+        """)
+        result = testdir.runpytest("--override-ini", 'paths=foo/bar1.py foo/bar2.py', "-s")
+        result.stdout.fnmatch_lines([
+            "user_path:bar1.py",
+            "user_path:bar2.py"
+        ])