Fix legacy flags, deprecate them and remove --index-url (#2731)

Resolves https://github.com/tox-dev/tox/issues/2690

2 files changed, 53 insertions, 18 deletions

diff --git a/src/tox/session/cmd/legacy.py b/src/tox/session/cmd/legacy.py
index bb5e993f..e92c3d27 100644
--- a/src/tox/session/cmd/legacy.py
+++ b/src/tox/session/cmd/legacy.py
@@ -1,15 +1,21 @@
 from __future__ import annotations
 
 from pathlib import Path
+from typing import cast
 
-from tox.config.cli.parser import DEFAULT_VERBOSITY, ToxParser
+from packaging.requirements import InvalidRequirement, Requirement
+
+from tox.config.cli.parser import DEFAULT_VERBOSITY, Parsed, ToxParser
+from tox.config.loader.memory import MemoryLoader
+from tox.config.set_env import SetEnv
 from tox.plugin import impl
 from tox.session.cmd.run.common import env_run_create_flags
 from tox.session.cmd.run.parallel import OFF_VALUE, parallel_flags, run_parallel
 from tox.session.cmd.run.sequential import run_sequential
 from tox.session.state import State
+from tox.tox_env.python.pip.req_file import PythonDeps
 
-from ..env_select import CliEnv, register_env_select_flags
+from ..env_select import CliEnv, EnvSelector, register_env_select_flags
 from .devenv import devenv
 from .list_env import list_env
 from .show_config import show_config
@@ -54,16 +60,8 @@ def tox_add_option(parser: ToxParser) -> None:
     our.add_argument(
         "--pre",
         action="store_true",
-        help="install pre-releases and development versions of dependencies. This will pass the --pre option to"
-        "install_command (pip by default).",
-    )
-    our.add_argument(
-        "-i",
-        "--index-url",
-        action="append",
-        default=[],
-        metavar="url",
-        help="set indexserver url (if URL is of form name=url set the url for the 'name' indexserver, specifically)",
+        help="deprecated use PIP_PRE in set_env instead - install pre-releases and development versions of"
+        "dependencies; this will set PIP_PRE=1 environment variable",
     )
     our.add_argument(
         "--force-dep",
@@ -72,17 +70,18 @@ def tox_add_option(parser: ToxParser) -> None:
         default=[],
         help="Forces a certain version of one of the dependencies when configuring the virtual environment. REQ "
         "Examples 'pytest<6.1' or 'django>=2.2'.",
+        type=Requirement,
     )
     our.add_argument(
         "--sitepackages",
         action="store_true",
-        help="override sitepackages setting to True in all envs",
+        help="deprecated use VIRTUALENV_SYSTEM_SITE_PACKAGES=1, override sitepackages setting to True in all envs",
         dest="site_packages",
     )
     our.add_argument(
         "--alwayscopy",
         action="store_true",
-        help="override always copy setting to True in all envs",
+        help="deprecated use VIRTUALENV_ALWAYS_COPY=1, override always copy setting to True in all envs",
         dest="always_copy",
     )
 
@@ -92,12 +91,17 @@ def legacy(state: State) -> int:
     if option.show_config:
         option.list_keys_only = []
         option.show_core = not bool(option.env)
-        return show_config(state)
     if option.list_envs or option.list_envs_all:
         state.envs.on_empty_fallback_py = False
         option.list_no_description = option.verbosity <= DEFAULT_VERBOSITY
         option.list_default_only = not option.list_envs_all
         option.show_core = False
+
+    _handle_legacy_only_flags(option, state.envs)
+
+    if option.show_config:
+        return show_config(state)
+    if option.list_envs or option.list_envs_all:
         return list_env(state)
     if option.devenv_path:
         option.devenv_path = Path(option.devenv_path)
@@ -105,3 +109,35 @@ def legacy(state: State) -> int:
     if option.parallel != 0:  # only 0 means sequential
         return run_parallel(state)
     return run_sequential(state)
+
+
+def _handle_legacy_only_flags(option: Parsed, envs: EnvSelector) -> None:
+    override = {}
+    if getattr(option, "site_packages", False):
+        override["system_site_packages"] = True
+    if getattr(option, "always_copy", False):
+        override["always_copy"] = True
+    set_env = {}
+    if getattr(option, "pre", False):
+        set_env["PIP_PRE"] = "1"
+    forced = {j.name: j for j in getattr(option, "force_dep", [])}
+    if override or set_env or forced:
+        for env in envs.iter(only_active=True, package=False):
+            env_conf = envs[env].conf
+            if override:
+                env_conf.loaders.insert(0, MemoryLoader(**override))
+            if set_env:
+                cast(SetEnv, env_conf["set_env"]).update(set_env, override=True)
+            if forced:
+                to_force = forced.copy()
+                deps = cast(PythonDeps, env_conf["deps"])
+                as_root_args = deps.as_root_args
+                for at, entry in enumerate(as_root_args):
+                    try:
+                        req = Requirement(entry)
+                    except InvalidRequirement:
+                        continue
+                    if req.name in to_force:
+                        as_root_args[at] = str(to_force[req.name])
+                        del to_force[req.name]
+                as_root_args.extend(str(v) for v in to_force.values())
diff --git a/src/tox/tox_env/python/virtual_env/api.py b/src/tox/tox_env/python/virtual_env/api.py
index 01bdc627..f2b87a43 100644
--- a/src/tox/tox_env/python/virtual_env/api.py
+++ b/src/tox/tox_env/python/virtual_env/api.py
@@ -112,10 +112,9 @@ class VirtualEnv(Python):
         base_python: list[str] = self.conf["base_python"]
         if "VIRTUALENV_NO_PERIODIC_UPDATE" not in env:
             env["VIRTUALENV_NO_PERIODIC_UPDATE"] = "True"
-        site = getattr(self.options, "site_packages", False) or self.conf["system_site_packages"]
         env["VIRTUALENV_CLEAR"] = "False"
-        env["VIRTUALENV_SYSTEM_SITE_PACKAGES"] = str(site)
-        env["VIRTUALENV_COPIES"] = str(getattr(self.options, "always_copy", False) or self.conf["always_copy"])
+        env["VIRTUALENV_SYSTEM_SITE_PACKAGES"] = str(self.conf["system_site_packages"])
+        env["VIRTUALENV_COPIES"] = str(self.conf["always_copy"])
         env["VIRTUALENV_DOWNLOAD"] = str(self.conf["download"])
         env["VIRTUALENV_PYTHON"] = "\n".join(base_python)
         if hasattr(self.options, "discover"):