Nushell activation scripts (#2170)

.github/workflows/check.yml

@@ -40,8 +40,14 @@ jobs:
         run: |
           for i in 1 2 3; do
             echo "try $i" && \
-            ${{ runner.os == 'Linux' && 'sudo apt-get update -y && sudo apt-get install fish csh' || true}} && \
-            ${{ runner.os == 'macOS' && 'brew install fish tcsh' || true}} && \
+            ${{ runner.os == 'Linux' && 'sudo apt-get update -y && sudo apt-get install fish csh -y' || true }} && \
+            ${{ runner.os == 'Linux' && 'sudo apt-get install curl wget -y' || true }} && \
+            ${{ runner.os == 'Linux' && 'nushell_url=$(curl -s https://api.github.com/repos/nushell/nushell/releases/latest | grep "browser_" | cut -d\" -f4 | grep .tar.gz)' || true }} && \
+            ${{ runner.os == 'Linux' && 'wget -O nushell.tar.gz $nushell_url' || true }} && \
+            ${{ runner.os == 'Linux' && 'tar -zxf nushell.tar.gz --one-top-level=nushell --strip-components=2' || true }} && \
+            ${{ runner.os == 'Linux' && 'sudo cp nushell/nu /usr/bin' || true }} && \
+            ${{ runner.os == 'Windows' && 'choco install nushell' || true }} && \
+            ${{ runner.os == 'macOS' && 'brew update && brew install fish tcsh nushell' || true }} && \
             exit 0 || true;
           done
           exit 1

setup.cfg

@@ -66,6 +66,7 @@ virtualenv.activate =
     fish = virtualenv.activation.fish:FishActivator
     powershell = virtualenv.activation.powershell:PowerShellActivator
     python = virtualenv.activation.python:PythonActivator
+    nushell = virtualenv.activation.nushell:NushellActivator
 virtualenv.create =
     venv = virtualenv.create.via_global_ref.venv:Venv
     cpython3-posix = virtualenv.create.via_global_ref.builtin.cpython.cpython3:CPython3Posix
@@ -108,6 +109,7 @@ virtualenv.activation.bash = *.sh
 virtualenv.activation.batch = *.bat
 virtualenv.activation.cshell = *.csh
 virtualenv.activation.fish = *.fish
+virtualenv.activation.nushell = *.nu
 virtualenv.activation.powershell = *.ps1
 virtualenv.seed.wheels.embed = *.whl
 

src/virtualenv/activation/__init__.py

@@ -4,6 +4,7 @@
 from .batch import BatchActivator
 from .cshell import CShellActivator
 from .fish import FishActivator
+from .nushell import NushellActivator
 from .powershell import PowerShellActivator
 from .python import PythonActivator
 
@@ -14,4 +15,5 @@
     "PythonActivator",
     "BatchActivator",
     "FishActivator",
+    "NushellActivator",
 ]

src/virtualenv/activation/nushell/__init__.py

@@ -0,0 +1,28 @@
+from __future__ import absolute_import, unicode_literals
+
+import os
+
+from virtualenv.util.path import Path
+from virtualenv.util.six import ensure_text
+
+from ..via_template import ViaTemplateActivator
+
+
+class NushellActivator(ViaTemplateActivator):
+    def templates(self):
+        yield Path("activate.nu")
+        yield Path("deactivate.nu")
+
+    def replacements(self, creator, dest_folder):
+        # Due to nushell scoping, it isn't easy to create a function that will
+        # deactivate the environment. For that reason a __DEACTIVATE_PATH__
+        # replacement pointing to the deactivate.nu file is created
+
+        return {
+            "__VIRTUAL_PROMPT__": "" if self.flag_prompt is None else self.flag_prompt,
+            "__VIRTUAL_ENV__": ensure_text(str(creator.dest)),
+            "__VIRTUAL_NAME__": creator.env_name,
+            "__BIN_NAME__": ensure_text(str(creator.bin_dir.relative_to(creator.dest))),
+            "__PATH_SEP__": ensure_text(os.pathsep),
+            "__DEACTIVATE_PATH__": ensure_text(str(Path(dest_folder) / "deactivate.nu")),
+        }

src/virtualenv/activation/nushell/activate.nu

@@ -0,0 +1,40 @@
+# Setting all environment variables for the venv
+let virtual-env = "__VIRTUAL_ENV__"
+let bin = "__BIN_NAME__"
+let path-sep = "__PATH_SEP__"
+
+let old-path = ($nu.path | str collect ($path-sep))
+
+let venv-path = ([$virtual-env $bin] | path join)
+let new-path = ($nu.path | prepend $venv-path | str collect ($path-sep))
+
+# environment variables that will be batched loaded to the virtual env
+let new-env = ([
+    [name, value];
+    [PATH $new-path]
+    [_OLD_VIRTUAL_PATH $old-path]
+    [VIRTUAL_ENV $virtual-env]
+])
+
+load-env $new-env
+
+# Creating the new prompt for the session
+let virtual_prompt = (if ("__VIRTUAL_PROMPT__" != "") {
+    "__VIRTUAL_PROMPT__"
+} {
+    $virtual-env | path basename
+}
+)
+
+# If there is no default prompt, then only the env is printed in the prompt
+let new_prompt = (if ( config | select prompt | empty? ) {
+    ($"build-string '(char lparen)' '($virtual_prompt)' '(char rparen) ' ")
+} {
+    ($"build-string '(char lparen)' '($virtual_prompt)' '(char rparen) ' (config get prompt | str find-replace "build-string" "")")
+})
+let-env PROMPT_COMMAND = $new_prompt
+
+# We are using alias as the function definitions because only aliases can be
+# removed from the scope
+alias pydoc = python -m pydoc
+alias deactivate = source "__DEACTIVATE_PATH__"

src/virtualenv/activation/nushell/deactivate.nu

@@ -0,0 +1,11 @@
+# Setting the old path
+let path-name = (if ((sys).host.name == "Windows") { "Path" } { "PATH" })
+let-env $path-name = $nu.env._OLD_VIRTUAL_PATH
+
+# Unleting the environment variables that were created when activating the env
+unlet-env VIRTUAL_ENV
+unlet-env _OLD_VIRTUAL_PATH
+unlet-env PROMPT_COMMAND
+
+unalias pydoc
+unalias deactivate

tests/unit/activation/test_nushell.py

@@ -0,0 +1,26 @@
+from __future__ import absolute_import, unicode_literals
+
+import sys
+
+if sys.version_info > (3,):
+    from shutil import which
+else:
+    from distutils.spawn import find_executable as which
+
+
+from virtualenv.activation import NushellActivator
+from virtualenv.info import IS_WIN
+
+
+def test_nushell(activation_tester_class, activation_tester):
+    class Nushell(activation_tester_class):
+        def __init__(self, session):
+            cmd = which("nu")
+            if cmd is None and IS_WIN:
+                cmd = "c:\\program files\\nu\\bin\\nu.exe"
+
+            super(Nushell, self).__init__(NushellActivator, session, cmd, "activate.nu", "nu")
+
+            self.unix_line_ending = not IS_WIN
+
+    activation_tester(Nushell)