Use red text when printing errors on command line

AUTHORS

@@ -26,3 +26,4 @@ Wasim Thabraze <wasim@thabraze.me>
 Varun Kamath <varunkamath18@gmail.com>
 Brian Rutledge <bhrutledge@gmail.com>
 Peter Stensmyr <peter.stensmyr@gmail.com> (http://www.peterstensmyr.com)
+Felipe Rocha Campos <felipecampos@google.com>

mypy.ini

@@ -18,6 +18,10 @@ warn_return_any = True
 no_implicit_reexport = True
 strict_equality = True
 
+[mypy-colorama]
+; https://github.com/tartley/colorama/issues/206
+ignore_missing_imports = True
+
 [mypy-importlib_metadata]
 ; https://gitlab.com/python-devs/importlib_metadata/-/issues/10
 ignore_missing_imports = True

setup.cfg

@@ -43,6 +43,7 @@ install_requires=
     importlib_metadata; python_version < "3.8"
     keyring >= 15.1
     rfc3986 >= 1.4.0
+    colorama >= 0.4.3
 setup_requires =
     setuptools_scm >= 1.15
 include_package_data = True

tests/test_main.py

@@ -10,6 +10,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import colorama
 import pretend
 
 from twine import __main__ as dunder_main
@@ -20,4 +21,7 @@
 def test_exception_handling(monkeypatch):
     replaced_dispatch = pretend.raiser(exceptions.InvalidConfiguration("foo"))
     monkeypatch.setattr(cli, "dispatch", replaced_dispatch)
-    assert dunder_main.main() == "InvalidConfiguration: foo"
+    assert (
+        dunder_main.main()
+        == colorama.Fore.RED + "InvalidConfiguration: foo" + colorama.Style.RESET_ALL
+    )

twine/__main__.py

@@ -20,12 +20,25 @@
 from twine import cli
 from twine import exceptions
 
+try:
+    import colorama
+except Exception:
+    colorama = None
+
 
 def main() -> Any:
     try:
+        if colorama:
+            colorama.init()
         return cli.dispatch(sys.argv[1:])
     except (exceptions.TwineException, requests.HTTPError) as exc:
-        return "{}: {}".format(exc.__class__.__name__, exc.args[0])
+        pre_style, post_style = "", ""
+        if colorama:
+            pre_style, post_style = colorama.Fore.RED, colorama.Style.RESET_ALL
+
+        return "{}{}: {}{}".format(
+            pre_style, exc.__class__.__name__, exc.args[0], post_style,
+        )
 
 
 if __name__ == "__main__":