Improve the shell command (#1395)

poetry.lock

@@ -671,6 +671,17 @@ version = "1.0"
 
 [[package]]
 category = "main"
+description = "Pexpect allows easy control of interactive console applications."
+name = "pexpect"
+optional = false
+python-versions = "*"
+version = "4.7.0"
+
+[package.dependencies]
+ptyprocess = ">=0.5"
+
+[[package]]
+category = "main"
 description = "Query metadatdata from sdists / bdists / installed packages."
 name = "pkginfo"
 optional = false
@@ -724,6 +735,14 @@ python = "<3.7"
 version = "*"
 
 [[package]]
+category = "main"
+description = "Run a subprocess in a pseudo terminal"
+name = "ptyprocess"
+optional = false
+python-versions = "*"
+version = "0.6.0"
+
+[[package]]
 category = "dev"
 description = "library with cross-python path, ini-parsing, io, code, log facilities"
 name = "py"
@@ -1185,7 +1204,7 @@ docs = ["sphinx", "jaraco.packaging (>=3.2)", "rst.linker (>=1.9)"]
 testing = ["pathlib2", "contextlib2", "unittest2"]
 
 [metadata]
-content-hash = "ce3f588df2abd05fc628ef84a79d494d60ab722745effd758765870c91d42b5e"
+content-hash = "fef0a14e6eed6d3fd20670fe4c048b1f17bc12a08a8b8a5482dfcff6f569cb1d"
 python-versions = "~2.7 || ^3.4"
 
 [metadata.hashes]
@@ -1240,9 +1259,11 @@ packaging = ["28b924174df7a2fa32c1953825ff29c61e2f5e082343165438812f00d3a7fc47",
 pastel = ["a904e1659512cc9880a028f66de77cc813a4c32f7ceb68725cbc8afad57ef7ef", "bf3b1901b2442ea0d8ab9a390594e5b0c9584709d543a3113506fe8b28cbace3"]
 pathlib2 = ["2156525d6576d21c4dcaddfa427fae887ef89a7a9de5cbfe0728b3aafa78427e", "446014523bb9be5c28128c4d2a10ad6bb60769e78bd85658fe44a450674e0ef8"]
 pep562 = ["58cb1cc9ee63d93e62b4905a50357618d526d289919814bea1f0da8f53b79395", "d2a48b178ebf5f8dd31709cc26a19808ef794561fa2fe50ea01ea2bad4d667ef"]
+pexpect = ["2094eefdfcf37a1fdbfb9aa090862c1a4878e5c7e0e7e7088bdb511c558e5cd1", "9e2c1fd0e6ee3a49b28f95d4b33bc389c89b20af6a1255906e90ff1262ce62eb"]
 pkginfo = ["7424f2c8511c186cd5424bbf31045b77435b37a8d604990b79d4e70d741148bb", "a6d9e40ca61ad3ebd0b72fbadd4fba16e4c0e4df0428c041e01e06eb6ee71f32"]
 pluggy = ["0db4b7601aae1d35b4a033282da476845aa19185c1e6964b25cf324b5e4ec3e6", "fa5fa1622fa6dd5c030e9cad086fa19ef6a0cf6d7a2d12318e10cb49d6d68f34"]
 pre-commit = ["1d3c0587bda7c4e537a46c27f2c84aa006acc18facf9970bf947df596ce91f3f", "fa78ff96e8e9ac94c748388597693f18b041a181c94a4f039ad20f45287ba44a"]
+ptyprocess = ["923f299cc5ad920c68f2bc0bc98b75b9f838b93b599941a6b63ddbc2476394c0", "d7cc528d76e76342423ca640335bd3633420dc1366f258cb31d05e865ef5ca1f"]
 py = ["64f65755aee5b381cea27766a3a147c3f15b9b6b9ac88676de66ba2ae36793fa", "dc639b046a6e2cff5bbe40194ad65936d6ba360b52b3c3fe1d08a82dd50b5e53"]
 pycparser = ["a988718abfad80b6b157acce7bf130a30876d27603738ac39f140993246b25b3"]
 pygments = ["5ffada19f6203563680669ee7f53b64dabbeb100eb51b61996085e99c03b284a", "e8218dd399a61674745138520d0d4cf2621d7e032439341bc3f647bff125818d", "71e430bc85c88a430f000ac1d9b331d2407f681d6f6aec95e8bcfbc3df5b0127", "881c4c157e45f30af185c1ffe8d549d48ac9127433f2c380c24b84572ad66297"]

poetry/console/commands/shell.py

@@ -36,5 +36,5 @@ If one doesn't exist yet, it will be created.
         # Setting this to avoid spawning unnecessary nested shells
         environ["POETRY_ACTIVE"] = "1"
         shell = Shell.get()
-        self.env.execute(shell.path)
+        shell.activate(self.env)
         environ.pop("POETRY_ACTIVE")

poetry/utils/shell.py

 import os
+import signal
+import sys
 
+import pexpect
+
+from clikit.utils.terminal import Terminal
 from shellingham import detect_shell
 from shellingham import ShellDetectionFailure
 
+from ._compat import WINDOWS
+from .env import VirtualEnv
+
 
 class Shell:
     """
@@ -40,5 +48,51 @@ class Shell:
 
         return cls._shell
 
+    def activate(self, env):  # type: (VirtualEnv) -> None
+        if WINDOWS:
+            return env.execute(self.path)
+
+        terminal = Terminal()
+        with env.temp_environ():
+            c = pexpect.spawn(
+                self._path, ["-i"], dimensions=(terminal.height, terminal.width)
+            )
+
+        c.setecho(False)
+        activate_script = self._get_activate_script()
+        bin_dir = "Scripts" if WINDOWS else "bin"
+        activate_path = env.path / bin_dir / activate_script
+        c.sendline("{} {}".format(self._get_source_command(), activate_path))
+
+        def resize(sig, data):
+            terminal = Terminal()
+            c.setwinsize(terminal.height, terminal.width)
+
+        signal.signal(signal.SIGWINCH, resize)
+
+        # Interact with the new shell.
+        c.interact(escape_character=None)
+        c.close()
+
+        sys.exit(c.exitstatus)
+
+    def _get_activate_script(self):
+        if "fish" == self._name:
+            suffix = ".fish"
+        elif "csh" == self._name:
+            suffix = ".csh"
+        else:
+            suffix = ""
+
+        return "activate" + suffix
+
+    def _get_source_command(self):
+        if "fish" == self._name:
+            return "source"
+        elif "csh" == self._name:
+            return "source"
+
+        return "."
+
     def __repr__(self):  # type: () -> str
         return '{}("{}", "{}")'.format(self.__class__.__name__, self._name, self._path)

pyproject.toml

@@ -35,6 +35,7 @@ pkginfo = "^1.4"
 html5lib = "^1.0"
 shellingham = "^1.1"
 tomlkit = "^0.5.5"
+pexpect = "^4.7.0"
 
 # The typing module is not in the stdlib in Python 2.7 and 3.4
 typing = { version = "^3.6", python = "~2.7 || ~3.4" }