Add tests to verify --index-url behaviour

tests/functional/test_install.py

@@ -1769,6 +1769,30 @@ def test_ignore_yanked_file(script, data):
     assert 'Successfully installed simple-2.0\n' in result.stdout, str(result)
 
 
+def test_invalid_index_url_argument(script):
+    """
+    Test the behaviour of an invalid --index-url argument
+    """
+
+    result = script.pip('install', '--index-url', '--user',
+                        TestPyPI.simple_url, 'simple',
+                        expect_error=True)
+
+    assert 'WARNING: index-url --user is invalid.' in \
+           result.stderr, str(result)
+
+
+def test_valid_index_url_argument(script):
+    """
+    Test the behaviour of an valid --index-url argument
+    """
+
+    result = script.pip('install', '--no-deps', '--index-url',
+                        TestPyPI.simple_url, 'simple')
+
+    assert 'Successfully installed simple' in result.stdout, str(result)
+
+
 def test_install_yanked_file_and_print_warning(script, data):
     """
     Test install a "yanked" file and print a warning.