Replace shell command with activator

pyproject.toml

@@ -42,7 +42,6 @@ installer = "^0.7.0"
 keyring = "^25.1.0"
 # packaging uses calver, so version is unclamped
 packaging = ">=24.0"
-pexpect = "^4.7.0"
 pkginfo = "^1.10"
 platformdirs = ">=3.0.0,<5"
 pyproject-hooks = "^1.0.0"

src/poetry/console/application.py

@@ -62,7 +62,6 @@ def _load() -> Command:
     "remove",
     "run",
     "search",
-    "shell",
     "show",
     "update",
     "version",
@@ -73,6 +72,7 @@ def _load() -> Command:
     "debug info",
     "debug resolve",
     # Env commands
+    "env activate",
     "env info",
     "env list",
     "env remove",

src/poetry/console/commands/env/activate.py

@@ -0,0 +1,64 @@
+from __future__ import annotations
+
+import shlex
+
+from typing import TYPE_CHECKING
+
+import shellingham
+
+from poetry.console.commands.command import Command
+from poetry.utils._compat import WINDOWS
+
+
+if TYPE_CHECKING:
+    from poetry.utils.env import Env
+
+
+class ShellNotSupportedError(Exception):
+    """Raised when a shell doesn't have an activator in virtual environment"""
+
+
+class EnvActivateCommand(Command):
+    name = "env activate"
+    description = "Print the command to activate a virtual environment"
+
+    def handle(self) -> int:
+        from poetry.utils.env import EnvManager
+
+        env = EnvManager(self.poetry).get()
+
+        if command := self.get_activate_command(env):
+            self.line(command)
+            return 0
+        else:
+            raise ShellNotSupportedError(
+                "Discovered shell doesn't have an activator in virtual environment"
+            )
+
+    def get_activate_command(self, env: Env) -> str:
+        try:
+            shell, _ = shellingham.detect_shell()
+        except shellingham.ShellDetectionFailure:
+            shell = ""
+        if shell == "fish":
+            command, filename = "source", "activate.fish"
+        elif shell == "nu":
+            command, filename = "overlay use", "activate.nu"
+        elif shell == "csh":
+            command, filename = "source", "activate.csh"
+        elif shell in ["powershell", "pwsh"]:
+            command, filename = ".", "Activate.ps1"
+        else:
+            command, filename = "source", "activate"
+
+        if (activation_script := env.bin_dir / filename).exists():
+            if WINDOWS:
+                return f"{self.quote(str(activation_script), shell)}"
+            return f"{command} {self.quote(str(activation_script), shell)}"
+        return ""
+
+    @staticmethod
+    def quote(command: str, shell: str) -> str:
+        if shell in ["powershell", "pwsh"] or WINDOWS:
+            return "{}".format(command.replace("'", "''"))
+        return shlex.quote(command)

src/poetry/utils/env/base_env.py

@@ -67,6 +67,10 @@ def __init__(self, path: Path, base: Path | None = None) -> None:
 
         self._embedded_pip_path: Path | None = None
 
+    @property
+    def bin_dir(self) -> Path:
+        return self._bin_dir
+
     @property
     def path(self) -> Path:
         return self._path