Integrate pytest warnings

CHANGELOG.rst

@@ -19,6 +19,10 @@ New Features
 * ``pytest.param`` can be used to declare test parameter sets with marks and test ids.
   Thanks `@RonnyPfannschmidt`_ for the PR.
 
+* The ``pytest-warnings`` plugin has been integrated into the core, so now ``pytest`` automatically
+  captures and displays warnings at the end of the test session.
+  Thanks `@nicoddemus`_ for the PR.
+
 
 Changes
 -------

_pytest/config.py

@@ -99,7 +99,7 @@ def directory_arg(path, optname):
      "mark main terminal runner python fixtures debugging unittest capture skipping "
      "tmpdir monkeypatch recwarn pastebin helpconfig nose assertion "
      "junitxml resultlog doctest cacheprovider freeze_support "
-     "setuponly setupplan").split()
+     "setuponly setupplan warnings").split()
 
 builtin_plugins = set(default_plugins)
 builtin_plugins.add("pytester")
@@ -911,11 +911,11 @@ def _ensure_unconfigure(self):
             fin = self._cleanup.pop()
             fin()
 
-    def warn(self, code, message, fslocation=None):
+    def warn(self, code, message, fslocation=None, nodeid=None):
         """ generate a warning for this test session. """
         self.hook.pytest_logwarning.call_historic(kwargs=dict(
             code=code, message=message,
-            fslocation=fslocation, nodeid=None))
+            fslocation=fslocation, nodeid=nodeid))
 
     def get_terminal_writer(self):
         return self.pluginmanager.get_plugin("terminalreporter")._tw

_pytest/fixtures.py

@@ -1081,7 +1081,7 @@ def parsefactories(self, node_or_obj, nodeid=NOTSET, unittest=False):
                     continue
                 marker = defaultfuncargprefixmarker
                 from _pytest import deprecated
-                self.config.warn('C1', deprecated.FUNCARG_PREFIX.format(name=name))
+                self.config.warn('C1', deprecated.FUNCARG_PREFIX.format(name=name), nodeid=nodeid)
                 name = name[len(self._argprefix):]
             elif not isinstance(marker, FixtureFunctionMarker):
                 # magic globals  with __getattr__ might have got us a wrong

_pytest/pytester.py

@@ -1008,7 +1008,7 @@ def spawn_pytest(self, string, expect_timeout=10.0):
         The pexpect child is returned.
 
         """
-        basetemp = self.tmpdir.mkdir("pexpect")
+        basetemp = self.tmpdir.mkdir("temp-pexpect")
         invoke = " ".join(map(str, self._getpytestargs()))
         cmd = "%s --basetemp=%s %s" % (invoke, basetemp, string)
         return self.spawn(cmd, expect_timeout=expect_timeout)

_pytest/python.py

@@ -936,7 +936,7 @@ def _idval(val, argname, idx, idfn, config=None):
             import warnings
             msg = "Raised while trying to determine id of parameter %s at position %d." % (argname, idx)
             msg += '\nUpdate your code as this will raise an error in pytest-4.0.'
-            warnings.warn(msg)
+            warnings.warn(msg, DeprecationWarning)
         if s:
             return _escape_strings(s)
 

_pytest/recwarn.py

@@ -56,14 +56,12 @@ def deprecated_call(func=None, *args, **kwargs):
 
     def warn_explicit(message, category, *args, **kwargs):
         categories.append(category)
-        old_warn_explicit(message, category, *args, **kwargs)
 
     def warn(message, category=None, *args, **kwargs):
         if isinstance(message, Warning):
             categories.append(message.__class__)
         else:
             categories.append(category)
-        old_warn(message, category, *args, **kwargs)
 
     old_warn = warnings.warn
     old_warn_explicit = warnings.warn_explicit

_pytest/runner.py

@@ -554,14 +554,21 @@ def importorskip(modname, minversion=None):
     __version__ attribute.  If no minversion is specified the a skip
     is only triggered if the module can not be imported.
     """
+    import warnings
     __tracebackhide__ = True
     compile(modname, '', 'eval') # to catch syntaxerrors
     should_skip = False
-    try:
-        __import__(modname)
-    except ImportError:
-        # Do not raise chained exception here(#1485)
-        should_skip = True
+
+    with warnings.catch_warnings():
+        # make sure to ignore ImportWarnings that might happen because
+        # of existing directories with the same name we're trying to
+        # import but without a __init__.py file
+        warnings.simplefilter('ignore')
+        try:
+            __import__(modname)
+        except ImportError:
+            # Do not raise chained exception here(#1485)
+            should_skip = True
     if should_skip:
         raise Skipped("could not import %r" %(modname,), allow_module_level=True)
     mod = sys.modules[modname]

_pytest/terminal.py

@@ -4,6 +4,7 @@
 """
 from __future__ import absolute_import, division, print_function
 
+import itertools
 from _pytest.main import EXIT_OK, EXIT_TESTSFAILED, EXIT_INTERRUPTED, \
     EXIT_USAGEERROR, EXIT_NOTESTSCOLLECTED
 import pytest
@@ -26,11 +27,11 @@ def pytest_addoption(parser):
          help="show extra test summary info as specified by chars (f)ailed, "
               "(E)error, (s)skipped, (x)failed, (X)passed, "
               "(p)passed, (P)passed with output, (a)all except pP. "
-              "The pytest warnings are displayed at all times except when "
-              "--disable-pytest-warnings is set")
-    group._addoption('--disable-pytest-warnings', default=False,
-                     dest='disablepytestwarnings', action='store_true',
-                     help='disable warnings summary, overrides -r w flag')
+              "Warnings are displayed at all times except when "
+              "--disable-warnings is set")
+    group._addoption('--disable-warnings', '--disable-pytest-warnings', default=False,
+                     dest='disable_warnings', action='store_true',
+                     help='disable warnings summary')
     group._addoption('-l', '--showlocals',
          action="store_true", dest="showlocals", default=False,
          help="show locals in tracebacks (disabled by default).")
@@ -59,9 +60,9 @@ def mywriter(tags, args):
 def getreportopt(config):
     reportopts = ""
     reportchars = config.option.reportchars
-    if not config.option.disablepytestwarnings and 'w' not in reportchars:
+    if not config.option.disable_warnings and 'w' not in reportchars:
         reportchars += 'w'
-    elif config.option.disablepytestwarnings and 'w' in reportchars:
+    elif config.option.disable_warnings and 'w' in reportchars:
         reportchars = reportchars.replace('w', '')
     if reportchars:
         for char in reportchars:
@@ -82,13 +83,40 @@ def pytest_report_teststatus(report):
             letter = "f"
     return report.outcome, letter, report.outcome.upper()
 
+
 class WarningReport(object):
+    """
+    Simple structure to hold warnings information captured by ``pytest_logwarning``.
+    """
     def __init__(self, code, message, nodeid=None, fslocation=None):
+        """
+        :param code: unused
+        :param str message: user friendly message about the warning
+        :param str|None nodeid: node id that generated the warning (see ``get_location``).
+        :param tuple|py.path.local fslocation:
+            file system location of the source of the warning (see ``get_location``).
+        """
         self.code = code
         self.message = message
         self.nodeid = nodeid
         self.fslocation = fslocation
 
+    def get_location(self, config):
+        """
+        Returns the more user-friendly information about the location
+        of a warning, or None.
+        """
+        if self.nodeid:
+            return self.nodeid
+        if self.fslocation:
+            if isinstance(self.fslocation, tuple) and len(self.fslocation) == 2:
+                filename, linenum = self.fslocation
+                relpath = py.path.local(filename).relto(config.invocation_dir)
+                return '%s:%d' % (relpath, linenum)
+            else:
+                return str(self.fslocation)
+        return None
+
 
 class TerminalReporter(object):
     def __init__(self, config, file=None):
@@ -168,8 +196,6 @@ def pytest_internalerror(self, excrepr):
 
     def pytest_logwarning(self, code, fslocation, message, nodeid):
         warnings = self.stats.setdefault("warnings", [])
-        if isinstance(fslocation, tuple):
-            fslocation = "%s:%d" % fslocation
         warning = WarningReport(code=code, fslocation=fslocation,
                                 message=message, nodeid=nodeid)
         warnings.append(warning)
@@ -440,13 +466,21 @@ def getreports(self, name):
 
     def summary_warnings(self):
         if self.hasopt("w"):
-            warnings = self.stats.get("warnings")
-            if not warnings:
+            all_warnings = self.stats.get("warnings")
+            if not all_warnings:
                 return
-            self.write_sep("=", "pytest-warning summary")
-            for w in warnings:
-                self._tw.line("W%s %s %s" % (w.code,
-                              w.fslocation, w.message))
+
+            grouped = itertools.groupby(all_warnings, key=lambda wr: wr.get_location(self.config))
+
+            self.write_sep("=", "warnings summary", yellow=True, bold=False)
+            for location, warnings in grouped:
+                self._tw.line(str(location) or '<undetermined location>')
+                for w in warnings:
+                    lines = w.message.splitlines()
+                    indented = '\n'.join('  ' + x for x in lines)
+                    self._tw.line(indented)
+                self._tw.line()
+            self._tw.line('-- Docs: http://doc.pytest.org/en/latest/warnings.html')
 
     def summary_passes(self):
         if self.config.option.tbstyle != "no":
@@ -548,8 +582,7 @@ def flatten(l):
 
 def build_summary_stats_line(stats):
     keys = ("failed passed skipped deselected "
-           "xfailed xpassed warnings error").split()
-    key_translation = {'warnings': 'pytest-warnings'}
+            "xfailed xpassed warnings error").split()
     unknown_key_seen = False
     for key in stats.keys():
         if key not in keys:
@@ -560,8 +593,7 @@ def build_summary_stats_line(stats):
     for key in keys:
         val = stats.get(key, None)
         if val:
-            key_name = key_translation.get(key, key)
-            parts.append("%d %s" % (len(val), key_name))
+            parts.append("%d %s" % (len(val), key))
 
     if parts:
         line = ", ".join(parts)

_pytest/warnings.py

@@ -0,0 +1,73 @@
+from __future__ import absolute_import, division, print_function
+
+import warnings
+from contextlib import contextmanager
+
+import pytest
+
+
+def _setoption(wmod, arg):
+    """
+    Copy of the warning._setoption function but does not escape arguments.
+    """
+    parts = arg.split(':')
+    if len(parts) > 5:
+        raise wmod._OptionError("too many fields (max 5): %r" % (arg,))
+    while len(parts) < 5:
+        parts.append('')
+    action, message, category, module, lineno = [s.strip()
+                                                 for s in parts]
+    action = wmod._getaction(action)
+    category = wmod._getcategory(category)
+    if lineno:
+        try:
+            lineno = int(lineno)
+            if lineno < 0:
+                raise ValueError
+        except (ValueError, OverflowError):
+            raise wmod._OptionError("invalid lineno %r" % (lineno,))
+    else:
+        lineno = 0
+    wmod.filterwarnings(action, message, category, module, lineno)
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("pytest-warnings")
+    group.addoption(
+        '-W', '--pythonwarnings', action='append',
+        help="set which warnings to report, see -W option of python itself.")
+    parser.addini("filterwarnings", type="linelist",
+                  help="Each line specifies warning filter pattern which would be passed"
+                  "to warnings.filterwarnings. Process after -W and --pythonwarnings.")
+
+
+@contextmanager
+def catch_warnings_for_item(item):
+    """
+    catches the warnings generated during setup/call/teardown execution
+    of the given item and after it is done posts them as warnings to this
+    item.
+    """
+    args = item.config.getoption('pythonwarnings') or []
+    inifilters = item.config.getini("filterwarnings")
+    with warnings.catch_warnings(record=True) as log:
+        warnings.simplefilter('once')
+        for arg in args:
+            warnings._setoption(arg)
+
+        for arg in inifilters:
+            _setoption(warnings, arg)
+
+        yield
+
+        for warning in log:
+            msg = warnings.formatwarning(
+                warning.message, warning.category,
+                warning.filename, warning.lineno, warning.line)
+            item.warn("unused", msg)
+
+
+@pytest.hookimpl(hookwrapper=True)
+def pytest_runtest_protocol(item):
+    with catch_warnings_for_item(item):
+        yield

doc/en/contents.rst

@@ -18,7 +18,7 @@ Full pytest documentation
    monkeypatch
    tmpdir
    capture
-   recwarn
+   warnings
    doctest
    mark
    skipping

doc/en/customize.rst

@@ -240,3 +240,23 @@ Builtin configuration file options
    By default, pytest will stop searching for ``conftest.py`` files upwards
    from ``pytest.ini``/``tox.ini``/``setup.cfg`` of the project if any,
    or up to the file-system root.
+
+
+.. confval:: filterwarnings
+
+   .. versionadded:: 3.1
+
+   Sets a list of filters and actions that should be taken for matched
+   warnings. By default all warnings emitted during the test session
+   will be displayed in a summary at the end of the test session.
+
+   .. code-block:: ini
+
+        # content of pytest.ini
+        [pytest]
+        filterwarnings =
+            error
+            ignore::DeprecationWarning
+
+   This tells pytest to ignore deprecation warnings and turn all other warnings
+   into errors. For more information please refer to :ref:`warnings`.