gh-159498: Fix PowerShell venv activation for paths containing brackets

Lib/test/test_venv.py

@@ -7,6 +7,7 @@
 
 import contextlib
 import ensurepip
+import json
 import os
 import os.path
 import pathlib
@@ -846,6 +847,42 @@ def test_fish_activate_shadowed_builtins(self):
         self.assertNotIn('LEAK', text)
         self.assertIn('OLDSTATUS=7', text)
 
+    @requires_subprocess()
+    def test_powershell_activate_literal_paths(self):
+        shells = [path for name in ('pwsh', 'powershell.exe')
+                  if (path := shutil.which(name)) is not None]
+        if not shells:
+            self.skipTest('PowerShell required for this test')
+
+        env_dir = self.get_env_file('venv[1]')
+        venv.EnvBuilder(prompt='from-config').create(env_dir)
+        activate = os.path.join(env_dir, self.bindir, 'Activate.ps1')
+        activate = activate.replace("'", "''")
+        test_script = self.get_env_file('test_literal_paths.ps1')
+        code = ('import json, os, sys; '
+                'print(json.dumps([sys.executable, '
+                "os.environ['VIRTUAL_ENV'], "
+                "os.environ['VIRTUAL_ENV_PROMPT']]))")
+        with open(test_script, 'w', encoding='utf-8-sig') as f:
+            f.write(
+                "$ErrorActionPreference = 'Stop'\n"
+                f". '{activate}'\n"
+                f'{self.exe} -c "{code}"\n'
+                'deactivate\n'
+            )
+        for shell in shells:
+            with self.subTest(shell=shell):
+                out, err = check_output(
+                    [shell, '-NoProfile', '-NonInteractive',
+                     '-ExecutionPolicy', 'Bypass', '-File', test_script],
+                )
+                self.assertFalse(err)
+                executable, active_dir, prompt = json.loads(out)
+                self.assertEqual(pathlib.Path(active_dir), pathlib.Path(env_dir))
+                self.assertEqual(prompt, 'from-config')
+                self.assertEqual(pathlib.Path(executable),
+                                 pathlib.Path(env_dir, self.bindir, self.exe))
+
     # gh-124651: test quoted strings on Windows
     @unittest.skipUnless(os.name == 'nt', 'only relevant on Windows')
     def test_special_chars_windows(self):

Lib/venv/scripts/common/Activate.ps1

@@ -135,15 +135,15 @@ function Get-PyVenvConfig(
     Write-Verbose "Given ConfigDir=$ConfigDir, obtain values in pyvenv.cfg"
 
     # Ensure the file exists, and issue a warning if it doesn't (but still allow the function to continue).
-    $pyvenvConfigPath = Join-Path -Resolve -Path $ConfigDir -ChildPath 'pyvenv.cfg' -ErrorAction Continue
+    $pyvenvConfigPath = Resolve-Path -LiteralPath (Join-Path -Path $ConfigDir -ChildPath 'pyvenv.cfg') -ErrorAction Continue
 
     # An empty map will be returned if no config file is found.
     $pyvenvConfig = @{ }
 
     if ($pyvenvConfigPath) {
 
         Write-Verbose "File exists, parse `key = value` lines"
-        $pyvenvConfigContent = Get-Content -Path $pyvenvConfigPath
+        $pyvenvConfigContent = Get-Content -LiteralPath $pyvenvConfigPath.ProviderPath
 
         $pyvenvConfigContent | ForEach-Object {
             $keyval = $PSItem -split "\s*=\s*", 2
@@ -168,7 +168,7 @@ function Get-PyVenvConfig(
 
 # Determine the containing directory of this script
 $VenvExecPath = Split-Path -Parent $MyInvocation.MyCommand.Definition
-$VenvExecDir = Get-Item -Path $VenvExecPath
+$VenvExecDir = Get-Item -LiteralPath $VenvExecPath
 
 Write-Verbose "Activation script is located in path: '$VenvExecPath'"
 Write-Verbose "VenvExecDir Fullname: '$($VenvExecDir.FullName)"

Misc/NEWS.d/next/Library/2026-10-16-01-44-47.gh-issue-159498.Lp9sQ2.rst

@@ -0,0 +1,2 @@
+Fix PowerShell activation of :mod:`venv` environments with square brackets
+in their paths, including reading the intended ``pyvenv.cfg`` file.