Print pip install output if verbosity is higher than default

Signed-off-by: Bernát Gábor <bgabor8@bloomberg.net>

src/tox/config/cli/parser.py

@@ -95,6 +95,7 @@ def _get_help_string(self, action: Action) -> Optional[str]:
 
 
 ToxParserT = TypeVar("ToxParserT", bound="ToxParser")
+DEFAULT_VERBOSITY = 2
 
 
 class Parsed(Namespace):
@@ -159,7 +160,9 @@ def _add_base_options(self) -> None:
             f"verbosity=verbose-quiet, default {logging.getLevelName(LEVELS[3])}, map {level_map}",
         )
         verbosity = verbosity_group.add_mutually_exclusive_group()
-        verbosity.add_argument("-v", "--verbose", action="count", dest="verbose", help="increase verbosity", default=2)
+        verbosity.add_argument(
+            "-v", "--verbose", action="count", dest="verbose", help="increase verbosity", default=DEFAULT_VERBOSITY
+        )
         verbosity.add_argument("-q", "--quiet", action="count", dest="quiet", help="decrease verbosity", default=0)
 
         converter = StrConvert()
@@ -224,3 +227,10 @@ def _inject_default_cmd(self, args: Sequence[str]) -> Sequence[str]:
         new_args.extend(command_args)
         new_args.extend(args[reorganize_to + 1 :])
         return new_args
+
+
+__all__ = (
+    "DEFAULT_VERBOSITY",
+    "Parsed",
+    "ToxParser",
+)

src/tox/tox_env/python/virtual_env/api.py

@@ -9,7 +9,7 @@
 from virtualenv.create.creator import Creator
 from virtualenv.run.session import Session
 
-from tox.config.cli.parser import Parsed
+from tox.config.cli.parser import DEFAULT_VERBOSITY, Parsed
 from tox.config.sets import ConfigSet
 from tox.execute.api import Execute, Outcome
 from tox.execute.local_sub_process import LocalSubProcessExecutor
@@ -98,4 +98,9 @@ def install_python_packages(
         result.assert_success(self.logger)
 
     def perform_install(self, install_command: Sequence[str]) -> Outcome:
-        return self.execute(cmd=install_command, allow_stdin=False, run_id="install")
+        return self.execute(
+            cmd=install_command,
+            allow_stdin=False,
+            run_id="install",
+            show_on_standard=self.options.verbosity > DEFAULT_VERBOSITY,
+        )