add tests

pip/__init__.py

@@ -197,10 +197,6 @@ def main(args=None):
     if args is None:
         args = sys.argv[1:]
 
-    # Enable our Deprecation Warnings
-    for deprecation_warning in deprecation.DEPRECATIONS:
-        warnings.simplefilter("default", deprecation_warning, append=True)
-
     # Configure our deprecation warnings to be sent through loggers
     deprecation.install_warning_logger()
 

pip/utils/deprecation.py

@@ -27,11 +27,6 @@ class Python26DeprecationWarning(PipDeprecationWarning, Pending):
     pass
 
 
-DEPRECATIONS = [
-    RemovedInPip9Warning, RemovedInPip10Warning, Python26DeprecationWarning
-]
-
-
 # Warnings <-> Logging Integration
 
 
@@ -71,6 +66,9 @@ def _showwarning(message, category, filename, lineno, file=None, line=None):
 
 
 def install_warning_logger():
+    # Enable our Deprecation Warnings
+    warnings.simplefilter("default", PipDeprecationWarning, append=True)
+
     global _warnings_showwarning
 
     if _warnings_showwarning is None:

tests/functional/test_warning.py

@@ -0,0 +1,36 @@
+import pytest
+
+PY26_WARNING = "Python 2.6 is no longer supported"
+
+
+@pytest.mark.skipif("sys.version_info >= (2,7)")
+def test_python26_options(script):
+    result = script.run(
+        'python', '-m', 'pip.__main__', 'list', expect_stderr=True,
+    )
+    assert PY26_WARNING in result.stderr
+    result = script.run('python', '-W', 'ignore', '-m', 'pip.__main__', 'list')
+    assert result.stderr == ''
+
+
+@pytest.mark.skipif("sys.version_info < (2,7)")
+def test_environ(script, tmpdir):
+    """$PYTHONWARNINGS was added in python2.7"""
+    demo = tmpdir.join('warnings_demo.py')
+    demo.write('''
+from pip.utils import deprecation
+deprecation.install_warning_logger()
+
+from logging import basicConfig
+basicConfig()
+
+from warnings import warn
+warn("deprecated!", deprecation.PipDeprecationWarning)
+''')
+
+    result = script.run('python', demo, expect_stderr=True)
+    assert result.stderr == 'ERROR:pip.deprecations:DEPRECATION: deprecated!\n'
+
+    script.environ['PYTHONWARNINGS'] = 'ignore'
+    result = script.run('python', demo)
+    assert result.stderr == ''