Implement prompt consistency tests and harmonize all activate scripts (#1330)

See history of [bskinn/virtualenv:all-prompts branch](https://github.com/bskinn/virtualenv/commits/all-prompts), tip at
bskinn/virtualenv@67cda5f, for the actual sequence of
development of the prompt tests, leading to the first commit of the PR (e6a2b99)

10 files changed, 550 insertions, 57 deletions

diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
index 29c52c2..cd53c35 100644
--- a/CONTRIBUTING.rst
+++ b/CONTRIBUTING.rst
@@ -13,8 +13,13 @@ Contributor notes
 * Pull requests should be made against ``master`` branch, which is also our
   latest stable version.
 
-* All changes to files inside virtualenv_embedded should be integrated to
-  ``virtualenv.py`` with ``tox -e embed``
+* All changes to files inside virtualenv_embedded must be integrated to
+  ``virtualenv.py`` with ``tox -e embed``. The tox run will report failure
+  when changes are integrated, as a flag for CI.
+
+* The codebase must be linted with ``tox -e fix_lint`` before being merged.
+  The tox run will report failure when the linters revise code, as a flag
+  for CI.
 
 .. _git-flow: https://github.com/nvie/gitflow
 .. _coordinate development: http://nvie.com/posts/a-successful-git-branching-model/
diff --git a/docs/changelog/1330.bugfix.rst b/docs/changelog/1330.bugfix.rst
new file mode 100644
index 0000000..0d7072b
--- /dev/null
+++ b/docs/changelog/1330.bugfix.rst
@@ -0,0 +1,2 @@
+Add tests covering prompt manipulation during activation/deactivation,
+and harmonize behavior of all supported shells - by ``bskinn``
diff --git a/docs/development.rst b/docs/development.rst
index 6eee7d3..a7d72d1 100644
--- a/docs/development.rst
+++ b/docs/development.rst
@@ -17,7 +17,12 @@ Files in the ``virtualenv_embedded/`` subdirectory are embedded into
 single-file use of ``virtualenv.py`` without installing it). If your patch
 changes any file in ``virtualenv_embedded/``, run ``tox -e embed`` to update
 the embedded version of that file in ``virtualenv.py``; commit that and submit
-it as part of your patch / pull request.
+it as part of your patch / pull request. The tox run will report failure
+when changes are embedded, as a flag for CI.
+
+The codebase should be linted before a pull request is merged by running
+``tox -e fix_lint``. The tox run will report failure when any linting
+revisions are required, as a flag for CI.
 
 .. _pip development: https://pip.pypa.io/en/latest/development/
 .. _virtualenv repo: https://github.com/pypa/virtualenv/
diff --git a/docs/reference.rst b/docs/reference.rst
index e623a91..deec504 100644
--- a/docs/reference.rst
+++ b/docs/reference.rst
@@ -148,8 +148,10 @@ is the same as calling::
 
 .. envvar:: VIRTUAL_ENV_DISABLE_PROMPT
 
-   Any virtualenv created when this is set to a non-empty value will not have
-   it's :ref:`activate` modify the shell prompt.
+   Any virtualenv *activated* when this is set to a non-empty value will leave
+   the shell prompt unchanged during processing of the
+   :ref:`activate script <activate>`, rather than modifying it to indicate
+   the newly activated environment.
 
 
 Configuration File
diff --git a/tests/activation/test_prompts.py b/tests/activation/test_prompts.py
new file mode 100644
index 0000000..8db4662
--- /dev/null
+++ b/tests/activation/test_prompts.py
@@ -0,0 +1,440 @@
+"""test that prompt behavior is correct in supported shells"""
+from __future__ import absolute_import, unicode_literals
+
+import os
+import subprocess
+import sys
+from textwrap import dedent
+
+import pytest
+
+import virtualenv
+from virtualenv import IS_DARWIN, IS_WIN
+
+try:
+    from pathlib import Path
+except ImportError:
+    from pathlib2 import Path
+
+VIRTUAL_ENV_DISABLE_PROMPT = "VIRTUAL_ENV_DISABLE_PROMPT"
+
+# This must match the DEST_DIR provided in the ../conftest.py:clean_python fixture
+ENV_DEFAULT = "env"
+
+# This can be anything
+ENV_CUSTOM = "env_custom"
+
+# Standard prefix, surround the env name in parentheses and separate by a space
+PREFIX_DEFAULT = "({}) ".format(ENV_DEFAULT)
+
+# Arbitrary prefix for the environment that's provided a 'prompt' arg
+PREFIX_CUSTOM = "---ENV---"
+
+# Temp script filename template: {shell}.script.(normal|suppress).(default|custom)[extension]
+SCRIPT_TEMPLATE = "{}.script.{}.{}{}"
+
+# Temp output filename template: {shell}.out.(normal|suppress).(default|custom)
+OUTPUT_TEMPLATE = "{}.out.{}.{}"
+
+# For skipping shells not installed by default if absent on a contributor's system
+IS_INSIDE_CI = "CI_RUN" in os.environ
+
+
+# Py2 doesn't like unicode in the environment
+def env_compat(string):
+    return string.encode("utf-8") if sys.version_info.major < 3 else string
+
+
+class ShellInfo(object):
+    """Parent class for shell information for prompt testing."""
+
+    # Typo insurance
+    __slots__ = []
+
+    # Equality check based on .name, but only if both are not None
+    def __eq__(self, other):
+        if type(self) != type(other):
+            return False
+        if self.name is None or other.name is None:
+            return False
+        return self.name == other.name
+
+    # Helper formatting string
+    @property
+    def platform_incompat_msg(self):
+        return "No sane provision for {} on {{}} yet".format(self.name)
+
+    # Each shell must specify
+    name = None
+    avail_cmd = None
+    execute_cmd = None
+    prompt_cmd = None
+    activate_script = None
+
+    # Default values defined here
+    # 'preamble_cmd' *MUST NOT* emit anything to stdout!
+    testscript_extension = ""
+    preamble_cmd = ""
+    activate_cmd = "source "
+    deactivate_cmd = "deactivate"
+    clean_env_update = {}
+
+    # Skip check function; must be specified per-shell
+    platform_check_skip = None
+
+    # Test assert method for comparing activated prompt to deactivated.
+    # Default defined, but can be overridden per-shell. Takes the captured
+    # lines of output as the lone argument.
+    def overall_prompt_test(self, lines, prefix):
+        """Perform all tests on (de)activated prompts.
+
+        From a Python 3 perspective, 'lines' is expected to be *bytes*,
+        and 'prefix' is expected to be *str*.
+
+        Happily, this all seems to translate smoothly enough to 2.7.
+
+        """
+        # Prompts before activation and after deactivation should be identical.
+        assert lines[1] == lines[3], lines
+
+        # The .partition here operates on the environment marker text expected to occur
+        # in the prompt. A non-empty 'env_marker' thus tests that the correct marker text
+        # has been applied into the prompt string.
+        before, env_marker, after = lines[2].partition(prefix.encode("utf-8"))
+        assert env_marker != b"", lines
+
+        # Some shells need custom activated-prompt tests, so this is split into
+        # its own submethod.
+        self.activated_prompt_test(lines, after)
+
+    def activated_prompt_test(self, lines, after):
+        """Perform just the check for the deactivated prompt contents in the activated prompt text.
+
+        The default is a strict requirement that the portion of the activated prompt following the environment
+        marker must exactly match the non-activated prompt.
+
+        Some shells require weaker tests, due to idiosyncrasies.
+
+        """
+        assert after == lines[1], lines
+
+
+class BashInfo(ShellInfo):
+    name = "bash"
+    avail_cmd = "bash -c 'echo foo'"
+    execute_cmd = "bash"
+    prompt_cmd = 'echo "$PS1"'
+    activate_script = "activate"
+
+    def platform_check_skip(self):
+        if IS_WIN:
+            return self.platform_incompat_msg.format(sys.platform)
+
+
+class FishInfo(ShellInfo):
+    name = "fish"
+    avail_cmd = "fish -c 'echo foo'"
+    execute_cmd = "fish"
+    prompt_cmd = "fish_prompt; echo ' '"
+    activate_script = "activate.fish"
+
+    # Azure Devops doesn't set a terminal type, which breaks fish's colorization
+    # machinery in a way that spuriously fouls the activation script.
+    clean_env_update = {"TERM": "linux"}
+
+    def platform_check_skip(self):
+        if IS_WIN:
+            return self.platform_incompat_msg.format(sys.platform)
+
+    def activated_prompt_test(self, lines, after):
+        """Require a looser match here, due to interposed ANSI color codes.
+
+        This construction allows coping with the messiness of fish's ANSI codes for colorizing.
+        It's not as rigorous as I would like---it doesn't ensure no space is inserted between
+        a custom env prompt (argument to --prompt) and the base prompt---but it does provide assurance as
+        to the key pieces of content that should be present.
+
+        """
+        assert lines[1] in after, lines
+
+
+class CshInfo(ShellInfo):
+    name = "csh"
+    avail_cmd = "csh -c 'echo foo'"
+    execute_cmd = "csh"
+    prompt_cmd = r"set | grep -E 'prompt\s' | sed -E 's/^prompt\s+(.*)$/\1/'"
+    activate_script = "activate.csh"
+
+    # csh defaults to an unset 'prompt' in non-interactive shells
+    preamble_cmd = "set prompt=%"
+
+    def platform_check_skip(self):
+        if IS_WIN:
+            return self.platform_incompat_msg.format(sys.platform)
+
+    def activated_prompt_test(self, lines, after):
+        """Test with special handling on MacOS, which does funny things to stdout under (t)csh."""
+        if IS_DARWIN:
+            # Looser assert for (t)csh on MacOS, which prepends extra text to
+            # what gets sent to stdout
+            assert lines[1].endswith(after), lines
+        else:
+            # Otherwise, use the rigorous default
+            # Full 2-arg form for super() used for 2.7 compat
+            super(CshInfo, self).activated_prompt_test(lines, after)
+
+
+class XonshInfo(ShellInfo):
+    name = "xonsh"
+    avail_cmd = "xonsh -c 'echo foo'"
+    execute_cmd = "xonsh"
+    prompt_cmd = "print(__xonsh__.shell.prompt)"
+    activate_script = "activate.xsh"
+
+    # Sets consistent initial state
+    preamble_cmd = (
+        "$VIRTUAL_ENV = ''; $PROMPT = '{env_name}$ '; "
+        "$PROMPT_FIELDS['env_prefix'] = '('; $PROMPT_FIELDS['env_postfix'] = ') '"
+    )
+
+    def platform_check_skip(self):
+        if IS_WIN:
+            return "Provisioning xonsh on windows is unreliable"
+
+        if sys.version_info < (3, 4):
+            return "xonsh requires Python 3.4 at least"
+
+
+class CmdInfo(ShellInfo):
+    name = "cmd"
+    avail_cmd = "echo foo"
+    execute_cmd = ""
+    prompt_cmd = "echo %PROMPT%"
+    activate_script = "activate.bat"
+
+    testscript_extension = ".bat"
+    preamble_cmd = "@echo off & set PROMPT=$P$G"  # For consistent initial state
+    activate_cmd = "call "
+    deactivate_cmd = "call deactivate"
+
+    def platform_check_skip(self):
+        if not IS_WIN:
+            return self.platform_incompat_msg.format(sys.platform)
+
+
+class PoshInfo(ShellInfo):
+    name = "posh"
+    avail_cmd = "powershell 'echo foo'"
+    execute_cmd = "powershell -File "
+    prompt_cmd = "prompt"
+    activate_script = "activate.ps1"
+
+    testscript_extension = ".ps1"
+    activate_cmd = ". "
+
+    def platform_check_skip(self):
+        if not IS_WIN:
+            return self.platform_incompat_msg.format(sys.platform)
+
+
+SHELLINFO_LIST = [BashInfo(), FishInfo(), CshInfo(), XonshInfo(), CmdInfo(), PoshInfo()]
+
+
+@pytest.fixture(scope="module")
+def posh_execute_enabled(tmp_path_factory):
+    """Return check value for whether Powershell script execution is enabled.
+
+    Posh may be available interactively, but the security settings may not allow
+    execution of script files.
+
+    # Enable with:  PS> Set-ExecutionPolicy -scope currentuser -ExecutionPolicy Bypass -Force;
+    # Disable with: PS> Set-ExecutionPolicy -scope currentuser -ExecutionPolicy Restricted -Force;
+
+    """
+    if not IS_WIN:
+        return False
+
+    test_ps1 = tmp_path_factory.mktemp("posh_test") / "test.ps1"
+    with open(str(test_ps1), "w") as f:
+        f.write("echo 'foo bar baz'\n")
+
+    out = subprocess.check_output(["powershell", "-File", "{}".format(str(test_ps1))], shell=True)
+    return b"foo bar baz" in out
+
+
+@pytest.fixture(scope="module")
+def shell_avail(posh_execute_enabled):
+    """Generate mapping of ShellInfo.name strings to bools of shell availability."""
+    retvals = {si.name: subprocess.call(si.avail_cmd, shell=True) for si in SHELLINFO_LIST}
+    avails = {si.name: retvals[si.name] == 0 for si in SHELLINFO_LIST}
+
+    # Extra check for whether powershell scripts are enabled
+    avails[PoshInfo().name] = avails[PoshInfo().name] and posh_execute_enabled
+
+    return avails
+
+
+@pytest.fixture(scope="module")
+def custom_prompt_root(tmp_path_factory):
+    """Provide Path to root with default and custom venvs created."""
+    root = tmp_path_factory.mktemp("custom_prompt")
+    virtualenv.create_environment(
+        str(root / ENV_CUSTOM), prompt=PREFIX_CUSTOM, no_setuptools=True, no_pip=True, no_wheel=True
+    )
+
+    _, _, _, bin_dir = virtualenv.path_locations(str(root / ENV_DEFAULT))
+
+    bin_dir_name = os.path.split(bin_dir)[-1]
+
+    return root, bin_dir_name
+
+
+@pytest.fixture(scope="module")
+def clean_python_root(clean_python):
+    root = Path(clean_python[0]).resolve().parent
+    bin_dir_name = os.path.split(clean_python[1])[-1]
+
+    return root, bin_dir_name
+
+
+@pytest.fixture(scope="module")
+def get_work_root(clean_python_root, custom_prompt_root):
+    def pick_root(env):
+        if env == ENV_DEFAULT:
+            return clean_python_root
+        elif env == ENV_CUSTOM:
+            return custom_prompt_root
+        else:
+            raise ValueError("Invalid test virtualenv")
+
+    return pick_root
+
+
+@pytest.fixture(scope="function")
+def clean_env():
+    """Provide a fresh copy of the shell environment.
+
+    VIRTUAL_ENV_DISABLE_PROMPT is always removed, if present, because
+    the prompt tests assume it to be unset.
+
+    """
+    clean_env = os.environ.copy()
+    clean_env.pop(env_compat(VIRTUAL_ENV_DISABLE_PROMPT), None)
+    return clean_env
+
+
+SHELLINFO_LIST = [BashInfo(), FishInfo(), CshInfo(), XonshInfo(), CmdInfo(), PoshInfo()]
+
+
+@pytest.mark.parametrize("shell_info", SHELLINFO_LIST, ids=(lambda si: si.name))
+@pytest.mark.parametrize("env", [ENV_DEFAULT, ENV_CUSTOM])
+@pytest.mark.parametrize(("value", "disable"), [("", False), ("0", True), ("1", True)])
+def test_suppressed_prompt(shell_info, shell_avail, env, value, disable, get_work_root, clean_env):
+    """Confirm non-empty VIRTUAL_ENV_DISABLE_PROMPT suppresses prompt changes on activate."""
+    skip_test = shell_info.platform_check_skip()
+    if skip_test:
+        pytest.skip(skip_test)
+
+    if not IS_INSIDE_CI and not shell_avail[shell_info.name]:
+        pytest.skip(
+            "Shell '{}' not provisioned".format(shell_info.name)
+            + (" - is Powershell script execution disabled?" if shell_info == PoshInfo() else "")
+        )
+
+    script_name = SCRIPT_TEMPLATE.format(shell_info.name, "suppress", env, shell_info.testscript_extension)
+    output_name = OUTPUT_TEMPLATE.format(shell_info.name, "suppress", env)
+
+    clean_env.update({env_compat(VIRTUAL_ENV_DISABLE_PROMPT): env_compat(value)})
+
+    work_root = get_work_root(env)
+
+    # The extra "{prompt}" here copes with some oddity of xonsh in certain emulated terminal
+    # contexts: xonsh can dump stuff into the first line of the recorded script output,
+    # so we have to include a dummy line of output that can get munged w/o consequence.
+    with open(str(work_root[0] / script_name), "w") as f:
+        f.write(
+            dedent(
+                """\
+        {preamble}
+        {prompt}
+        {prompt}
+        {act_cmd}{env}/{bindir}/{act_script}
+        {prompt}
+    """.format(
+                    env=env,
+                    act_cmd=shell_info.activate_cmd,
+                    preamble=shell_info.preamble_cmd,
+                    prompt=shell_info.prompt_cmd,
+                    act_script=shell_info.activate_script,
+                    bindir=work_root[1],
+                )
+            )
+        )
+
+    command = "{} {} > {}".format(shell_info.execute_cmd, script_name, output_name)
+
+    assert 0 == subprocess.call(command, cwd=str(work_root[0]), shell=True, env=clean_env)
+
+    with open(str(work_root[0] / output_name), "rb") as f:
+        lines = f.read().split(b"\n")
+
+    # Is the prompt suppressed based on the env var value?
+    assert (lines[1] == lines[2]) == disable, lines
+
+
+@pytest.mark.parametrize("shell_info", SHELLINFO_LIST, ids=(lambda si: si.name))
+@pytest.mark.parametrize(["env", "prefix"], [(ENV_DEFAULT, PREFIX_DEFAULT), (ENV_CUSTOM, PREFIX_CUSTOM)])
+def test_activated_prompt(shell_info, shell_avail, env, prefix, get_work_root, clean_env):
+    """Confirm prompt modification behavior with and without --prompt specified."""
+    skip_test = shell_info.platform_check_skip()
+    if skip_test:
+        pytest.skip(skip_test)
+
+    if not IS_INSIDE_CI and not shell_avail[shell_info.name]:
+        pytest.skip(
+            "Shell '{}' not provisioned".format(shell_info.name)
+            + (" - is Powershell script execution disabled?" if shell_info == PoshInfo() else "")
+        )
+
+    for k, v in shell_info.clean_env_update.items():
+        clean_env.update({env_compat(k): env_compat(v)})
+
+    script_name = SCRIPT_TEMPLATE.format(shell_info.name, "normal", env, shell_info.testscript_extension)
+    output_name = OUTPUT_TEMPLATE.format(shell_info.name, "normal", env)
+
+    work_root = get_work_root(env)
+
+    # The extra "{prompt}" here copes with some oddity of xonsh in certain emulated terminal
+    # contexts: xonsh can dump stuff into the first line of the recorded script output,
+    # so we have to include a dummy line of output that can get munged w/o consequence.
+    with open(str(work_root[0] / script_name), "w") as f:
+        f.write(
+            dedent(
+                """\
+        {preamble}
+        {prompt}
+        {prompt}
+        {act_cmd}{env}/{bindir}/{act_script}
+        {prompt}
+        {deactivate}
+        {prompt}
+        """.format(
+                    env=env,
+                    act_cmd=shell_info.activate_cmd,
+                    deactivate=shell_info.deactivate_cmd,
+                    preamble=shell_info.preamble_cmd,
+                    prompt=shell_info.prompt_cmd,
+                    act_script=shell_info.activate_script,
+                    bindir=work_root[1],
+                )
+            )
+        )
+
+    command = "{} {} > {}".format(shell_info.execute_cmd, script_name, output_name)
+
+    assert 0 == subprocess.call(command, cwd=str(work_root[0]), shell=True, env=clean_env)
+
+    with open(str(work_root[0] / output_name), "rb") as f:
+        lines = f.read().split(b"\n")
+
+    shell_info.overall_prompt_test(lines, prefix)
diff --git a/virtualenv.py b/virtualenv.py
index 061e0d5..8184e86 100755
--- a/virtualenv.py
+++ b/virtualenv.py
@@ -1698,7 +1698,7 @@ def install_files(home_dir, bin_dir, prompt, files):
     virtualenv_name = os.path.basename(home_dir)
     for name, content in files.items():
         content = content.replace("__VIRTUAL_PROMPT__", prompt or "")
-        content = content.replace("__VIRTUAL_WINPROMPT__", prompt or "({})".format(virtualenv_name))
+        content = content.replace("__VIRTUAL_WINPROMPT__", prompt or "({}) ".format(virtualenv_name))
         content = content.replace("__VIRTUAL_ENV__", home_dir)
         content = content.replace("__VIRTUAL_NAME__", virtualenv_name)
         content = content.replace("__BIN_NAME__", os.path.basename(bin_dir))
@@ -2282,42 +2282,43 @@ a6FOZy1jZzukdvvqN1kPccDLjbwGdtJ8m72rgeki+xOnXcf/CzFcuJM=
 # file activate.csh
 ACTIVATE_CSH = convert(
     """
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+pVrULKj64Ysnt3/G19ObtgkCJrXzF74jRz2MaCnJgtcN5B7wLfK2DedOp4vGydPcet5urq2XBEZv
+DcnQpBZVJt0KUBqEa4YzpS0a3x7odFOm0Dlqe9oEkN8qVUlK01/iKfSa3LRRKmqkBc2vBKFpmyCs
+XG4d2yYyEQZBzIvKOgLN+JDveiVoaXyqedVYOkTrmCRqutrfNVHr6xMFBhh9QD/qNQuGLvq72d03
+3Jy2CtGCf0rca/tp+N4BXqsflKquRr0L2sjmuClOu+/8/NKvTQsNZ3l9ZqxeTew//1a6EA==
 """
 )
 
 # file activate.xsh
 ACTIVATE_XSH = convert(
     """
-eJyFU11rwjAUfc+vuIt9sMz1Bwg+OCYoaB2bkw2RkNlbLdSkJLFsjP33JdV+aN2Wh5L7eW7PuaGU
-vkqhd8A3Jsm5QdAblWQGYqkgT5Q58BRFTiklsZJ7+HDJgZEy1ZDsM6kMbNEwjRlwDex0JyTCGFiE
-ZdcuV1vt9wnYk8RAs89IbigkAniacI36GHInwrR0rk55a1IWel9BEHwHFqZL2Xz6wJaTp8XLcMoe
-h4sx7QGlft3Jc04YgNfKPAO7Ev4f7m0xnofj+WzUBq1Cbegq9NcAdVJFVxkbhcuCtONc55x5jaS6
-UkgRoTbq4IRACkKagnUrR13egWdMYygTb65rUavpBCEdOAiNtptSmGLOhYGcq4S/p6hJU/rV5RBr
-n1xtavlq1BHS/CMbU5SxhocxalNa2jnSCw29prXqr4+OgEdR96zxbbW1Xd8aFuR+ErJwOBtZhB7Y
-rRdmsFAH7IHCLOUbLCyfkIsFub4TJU2NtbB11lNEf5O+mPt8WwqNm8tx+UhsjbubnRRugLu9+5YP
-6AcvDiI9
+eJyNU11PwjAUfe+vuNY9sIj7ASQ+YCSBRD6i02gIaSq7gyWjXdqyaIz/3XYwVmB+9GFZ78c57T2n
+lNIXKfQa+NJkJTcIeqmywkAqFZSZMlueoygppSRVcgPvrjgyUuYask0hlYEVGqaxAK6B7f8JSTAF
+lmCN2uFqpcMeAbuyFGjxkcglhUwAzzOuUe9SbiWY18H5vm5B6sbgM4qir8jSdCib3t+x59FD/NS/
+Z7N+PKRdoDRskAIXhBsIziqPyFrSf9O9xsPpZDgdD85JD6lz6kPqtwM0RYdx1bnB5Lka2u5cxzML
+vKLWTjZ7mI5n8b8A9rUNjpAiQW3U1gmKFIQ0lXpW1gblEh4xT6EuvGjXtHGFE5ZcwlZotGhKYY4l
+FwZKrjL+lqMmvoXmp4dYhKQV1M7d6yPEv5jNKcqYf1VGbcmZB5x4lRcCfzfvLXaBiCdJ5wj46uD+
+Tmg3luR2NGGT/nhgGbpgX48wN7HaYhcUFjlfYrULCTkxWru36jF59rJ9NlJlf7JQde5j11VS+yZr
+0d22eUPaxdycLKMTvqWjR3610emDtgTu36ylcJe83rhv/di/AYN1UZY=
 """
 )
 
 # file activate.bat
 ACTIVATE_BAT = convert(
     """
-eJx9Ul9LhEAQfxf8DoOclI/dYyFkaCmcq4gZQTBUrincuZFbff12T133TM+nnd35/Zvxlr7XDFhV
-mUZHOVhFlOWP3g4DUriIWoVomYZpNBWUtGpaWgImO191pFkSpzlcmgaI70jVX7n2Qp8tuByg+46O
-CMHbMq64T+nmlJt082D1T44muCDk2prgEHF4mdI9RaS/QwSt3zSyIAaftRccvqVTBziD1x/WlPD5
-xd729NDBb8Nr4DU9QNMKsJeH9pkhPedhQsIkDuCDCa6A+NF9IevVFAohkqizdHetg/tkWvPoftWJ
-MCqnOxv7/x7Np6yv9P2Ker5dmX8yNyCkkWnbZy3N5LarczlqL8htx2EM9rQ/2H5BvIsIEi8OEG8U
-+g8CsNTr
+eJyVk1FLhEAUhd8X/A8XWSkf28dCyMUpBR3FzAiCS+WYwq4TOdXfb0Z3dTJdyCfveO85n8frNXut
+OPCyNFbGqmUCzDxIs3s3REJzB1GrEE3VVJdQsLJuWAEYh97QkaRxlGRwbqxAXp1Uf+RYM32W1LKB
+7Vp2nJC6DReD9m+5qeQ6Wd+a/SN7dlzn9oI7dxsSXJCcoXOskfLgYXdv/j8LnXiM8iGg/RmiZmOr
+bFMSgcebMwGfKhgbBIfnL14X8P7BX3Zs38J3LSoQFdtD3YCVuJlvnfgmj5kfUz+OCLxxqUWoF9zk
+qtYAFyZkBsO9ArzUh/td0ZqP9IskElTFMsnwb4/GqeoLPUlZT5dJvf8Id5hQIONynUSa2G0Wc+m8
+Z+w2w4/Tt2hbYT0hbgOK1I0I4tUw/QOTZfLE
 """
 )
 
@@ -2334,17 +2335,18 @@ pk+k4fAba/wd0Pr4P2CqyLeOlJ4iKfkJo6v/iaH9YzfPMEoeMG2RUA==
 # file activate.ps1
 ACTIVATE_PS = convert(
     """
-eJyNVMtu2zAQvOsrNrLQ2miloFcXPdiwgRhwHCN2c2kLgqZWMQGKFEhKqVHky3LoJ/UXSlqWX3LS
-8ibtzHJ2d5Z/Xn53YLnmBjIuEPLSWFghpMqCUaVmmEKmVQ5ztVh/ho0qgVEpXVSXEriFlGtkVmwS
-GCmwLk8fEkiuKbO8ohaTwnwKgsgwzQvbX95MFmQ+WN7AF4jyDZeVYtRyJZN8w1SeU5kmBbXrPWE4
-WIzJaHLv8KYQ3MY+Cl2NRokK668w2qe9TpKwB/GcapQ2CLJSMp8dHoVaUdFPsZHV/WaeuGXrHxDN
-lByhsbr0IewFvwJwh2fQte53fUVFNacrgX1yNx2Rh8n98utgur2xt0XXHH8ilFW/qfB12h6vMVeu
-kAYJYQsaQmyYKnBXxJb5HFwQ2VTbJ0qkpOLallSQwg2vsC2Ze3Ad92rf4p/r5Rbzw4XfX2Mc6dw2
-pqlrPHtoKfIpHOZ00ucsiAXS7KKaFhK1VprWBjDO29K5lClpuSzxXN1Vywan6jqwQJFBukNcvd2P
-g8/exhWbVLGdlOe2XetwLaLY2LWLxDls/0JE9aPxpA6U0qAFrjUKrKi0e7ea4CAEYqlkeijQ7eRx
-s9z4m1ULWj13waNPx9zpa1nVIxv/B8ebEJ7nvCZkOJmR2eB2TNzxMLIYzwkJ4cNRjno0Z1wncjEY
-Tsdkfn93O182G3vevdc8eRhqGO56f7oRF4gn63GUqzWxS9d0YJCmQKHQmPGfYP0zicBK7R8pqCkf
-YVW6t1TJ9/5FNYzq1D2uyT7Hk3bOidfKPc5hN+r+e0Wg14NwO3R8ElwejPjuPxbdu/EvkRDrCw==
+eJytVcFu2zAMvfsrWNfYEmx2sWuGHVIkQAO0adBkvWyDoMh0I0CWDElOGwz598p2HDt20w3YdLP5
+SD2Sj9QlrDbcQMIFQpobC2uEWFkwKtcMY0i0SmGhlpuvsFM5MCqls+pcArcQc43Mil0EEwXWxRlB
+BNEVZZZvqcUoM188LzBM88yOVjezJVmMVzfwDYJ0x+VWMWq5klG6YypNqYyjjNrN0eF6vJySyezB
+4U0muA0LKww0GiW2WH35wTHsVRT5QwgXVKO0npfkkhXR4UmoNRWjGGtagx/mmVu2+QXBXMkJGqvz
+woRD77cH7vAEBtb9rq7YUs3pWuCI3N9OyOPsYfV9fFveOCzRlU9xApTbUZ3hebcjXmOqXCI1Evwe
+1IfQMJXhIYnSc++9QbLOdkSUiMmWa5tTQTLXvMz2aB7Blb1g+55/ly+3mDYX/jzn0eJZFqbOazp/
+7DEqQjjMaae7XhAKpMmbbHpI1FppWgnAOG1Lp1KmpOUyxy67i54MTtldwhJFAvEBcfF+PRqdvY/L
+drFiByr7vlwrc0Ui29mNs4QplH8hoPrJFE6XkEuDFrjWKHBLpT2q1XgNEQilknGToJvJdrFc++tR
+83o1d8bWp/M88OtJtUDW+vfak+B3Y14Rcj2bk/n4bkrcKWBkOV0Q4sOnVoyqNR1fR3I5vr6dksXD
+/d1iVU9st3rnNNk01fcPtT+diDccT8ajFavg55OmBiWhIolQulH2uyrqNfh0thpgJblxHLuNisDc
+TnYbONOY8BewqvyJL9w4KT9BJ0hxnrXTWbhRbpWfYackPgsu8cTtw1/ugH2rbCgM/nuWtJMcy3Wx
+wQ+5fYZ17h4aJT8Wz41hVMfu5YnOpjwIBn/eITAcwn+rxN57BRHvOEk=
 """
 )
 
diff --git a/virtualenv_embedded/activate.bat b/virtualenv_embedded/activate.bat
index ed42021..9c5d372 100644
--- a/virtualenv_embedded/activate.bat
+++ b/virtualenv_embedded/activate.bat
@@ -1,4 +1,5 @@
 @echo off
+
 set "VIRTUAL_ENV=__VIRTUAL_ENV__"
 
 if defined _OLD_VIRTUAL_PROMPT (
@@ -7,9 +8,13 @@ if defined _OLD_VIRTUAL_PROMPT (
     if not defined PROMPT (
         set "PROMPT=$P$G"
     )
-    set "_OLD_VIRTUAL_PROMPT=%PROMPT%"
+    if not defined VIRTUAL_ENV_DISABLE_PROMPT (
+        set "_OLD_VIRTUAL_PROMPT=%PROMPT%"
+    )
+)
+if not defined VIRTUAL_ENV_DISABLE_PROMPT (
+    set "PROMPT=__VIRTUAL_WINPROMPT__%PROMPT%"
 )
-set "PROMPT=__VIRTUAL_WINPROMPT__ %PROMPT%"
 
 REM Don't use () to avoid problems with them in %PATH%
 if defined _OLD_VIRTUAL_PYTHONHOME goto ENDIFVHOME
diff --git a/virtualenv_embedded/activate.csh b/virtualenv_embedded/activate.csh
index e3dc553..c4a6d58 100644
--- a/virtualenv_embedded/activate.csh
+++ b/virtualenv_embedded/activate.csh
@@ -20,22 +20,35 @@ setenv PATH "$VIRTUAL_ENV:q/__BIN_NAME__:$PATH:q"
 if ("__VIRTUAL_PROMPT__" != "") then
     set env_name = "__VIRTUAL_PROMPT__"
 else
-    set env_name = "$VIRTUAL_ENV:t:q"
+    set env_name = '('"$VIRTUAL_ENV:t:q"') '
 endif
 
-# Could be in a non-interactive environment,
-# in which case, $prompt is undefined and we wouldn't
-# care about the prompt anyway.
-if ( $?prompt ) then
-    set _OLD_VIRTUAL_PROMPT="$prompt:q"
-if ( "$prompt:q" =~ *"$newline:q"* ) then
-    :
+if ( $?VIRTUAL_ENV_DISABLE_PROMPT ) then
+    if ( $VIRTUAL_ENV_DISABLE_PROMPT == "" ) then
+        set do_prompt = "1"
+    else
+        set do_prompt = "0"
+    endif
 else
-    set prompt = "[$env_name:q] $prompt:q"
+    set do_prompt = "1"
 endif
+
+if ( $do_prompt == "1" ) then
+    # Could be in a non-interactive environment,
+    # in which case, $prompt is undefined and we wouldn't
+    # care about the prompt anyway.
+    if ( $?prompt ) then
+        set _OLD_VIRTUAL_PROMPT="$prompt:q"
+        if ( "$prompt:q" =~ *"$newline:q"* ) then
+            :
+        else
+            set prompt = "$env_name:q$prompt:q"
+        endif
+    endif
 endif
 
 unset env_name
+unset do_prompt
 
 alias pydoc python -m pydoc
 
diff --git a/virtualenv_embedded/activate.ps1 b/virtualenv_embedded/activate.ps1
index 48b947d..3bbf9a6 100644
--- a/virtualenv_embedded/activate.ps1
+++ b/virtualenv_embedded/activate.ps1
@@ -1,4 +1,4 @@
-# This file must be dot sourced from PoSh; you cannot run it directly. Do this: . ./activate.ps1

+# This file must be dot sourced from PoSh; you cannot run it directly. Do this: . ./activate.ps1

 

 $script:THIS_PATH = $myinvocation.mycommand.path

 $script:BASE_DIR = split-path (resolve-path "$THIS_PATH/..") -Parent

@@ -51,10 +51,22 @@ if (!$env:VIRTUAL_ENV_DISABLE_PROMPT)
         ""

     }

     $function:_old_virtual_prompt = $function:prompt

-    function global:prompt

+    if ("__VIRTUAL_PROMPT__" -ne "")

     {

-        # Add a prefix to the current prompt, but don't discard it.

-        write-host "($( split-path $env:VIRTUAL_ENV -leaf )) " -nonewline

-        & $function:_old_virtual_prompt

+        function global:prompt

+        {

+            # Add the custom prefix to the existing prompt

+            write-host "__VIRTUAL_PROMPT__" -nonewline

+            & $function:_old_virtual_prompt

+        }

+    }

+    else

+    {

+        function global:prompt

+        {

+            # Add a prefix to the current prompt, but don't discard it.

+            write-host "($( split-path $env:VIRTUAL_ENV -leaf )) " -nonewline

+            & $function:_old_virtual_prompt

+        }

     }

 }

diff --git a/virtualenv_embedded/activate.xsh b/virtualenv_embedded/activate.xsh
index 6eb0d59..c77ea62 100644
--- a/virtualenv_embedded/activate.xsh
+++ b/virtualenv_embedded/activate.xsh
@@ -16,6 +16,9 @@ def _deactivate(args):
     if "VIRTUAL_ENV" in ${...}:
         del $VIRTUAL_ENV
 
+    if "VIRTUAL_ENV_PROMPT" in ${...}:
+        del $VIRTUAL_ENV_PROMPT
+
     if "nondestructive" not in args:
         # Self destruct!
         del aliases["deactivate"]
@@ -36,4 +39,8 @@ if ${...}.get("PYTHONHOME", ""):
     $_OLD_VIRTUAL_PYTHONHOME = $PYTHONHOME
     del $PYTHONHOME
 
+$VIRTUAL_ENV_PROMPT = "__VIRTUAL_PROMPT__"
+if not $VIRTUAL_ENV_PROMPT:
+    del $VIRTUAL_ENV_PROMPT
+
 aliases["pydoc"] = ["python", "-m", "pydoc"]