Add a global option to disable colors

docs/reference/pip.rst

@@ -24,7 +24,9 @@ Console logging
 ~~~~~~~~~~~~~~~
 
 pip offers :ref:`-v, --verbose <--verbose>` and :ref:`-q, --quiet <--quiet>`
-to control the console log level.
+to control the console log level. By default, some messages (error and warnnings)
+are colored in the terminal. If you want to suppress the colored output use
+:ref:`--no-color <--no-color>`.
 
 
 .. _`FileLogging`:

news/2449.feature

@@ -0,0 +1,2 @@
+Add `--no-color` to `pip`. All colored output is disabled
+if this flag is detected.

src/pip/_internal/basecommand.py

@@ -151,15 +151,21 @@ def main(self, args):
                 "console": {
                     "level": level,
                     "class":
-                        "pip._internal.utils.logging.ColorizedStreamHandler",
+                    "logging.StreamHandler"
+                        if options.no_color
+                        else ("pip._internal.utils.logging."
+                              "ColorizedStreamHandler"),
                     "stream": self.log_streams[0],
                     "filters": ["exclude_warnings"],
                     "formatter": "indent",
                 },
                 "console_errors": {
                     "level": "WARNING",
                     "class":
-                        "pip._internal.utils.logging.ColorizedStreamHandler",
+                    "logging.StreamHandler"
+                        if options.no_color
+                        else ("pip._internal.utils.logging"
+                              ".ColorizedStreamHandler"),
                     "stream": self.log_streams[1],
                     "formatter": "indent",
                 },

src/pip/_internal/cmdoptions.py

@@ -102,6 +102,15 @@ def getname(n):
     help='Give more output. Option is additive, and can be used up to 3 times.'
 )
 
+no_color = partial(
+    Option,
+    '--no-color',
+    dest='no_color',
+    action='store_true',
+    default=False,
+    help="Suppress colored output"
+)
+
 version = partial(
     Option,
     '-V', '--version',
@@ -566,6 +575,7 @@ def _merge_hash(option, opt_str, value, parser):
         cache_dir,
         no_cache,
         disable_pip_version_check,
+        no_color
     ]
 }