Support Conda prompt prefixes

Author: jwodder

CHANGELOG.md

@@ -1,3 +1,7 @@
+v0.3.0 (in development)
+-----------------------
+- Support showing Conda environment prompt prefixes
+
 v0.2.2 (2021-07-11)
 -------------------
 - When inside a `.git` directory, treat it like a bare repository, thereby

README.rst

@@ -7,7 +7,8 @@ it's better.
 Features:
 
 - lets you know if you have mail in ``$MAIL``
-- shows chroot and `virtualenv <https://virtualenv.pypa.io>`_ prompt prefixes
+- shows chroot, `virtualenv <https://virtualenv.pypa.io>`_, and `Conda
+  <https://conda.io>`_ environment prompt prefixes
 - automatically truncates the current directory path if it gets too long
 - shows the status of the current Git repository (see below)
 - thoroughly documented and easily customizable

ps1.py

@@ -57,7 +57,7 @@
    by running ``PS1_GIT=off`` on the command line.
 """
 
-__version__      = '0.2.2'
+__version__      = '0.3.0.dev1'
 __author__       = 'John T. Wodder II'
 __author_email__ = 'ps1@varonathe.org'
 __license__      = 'MIT'
@@ -267,6 +267,12 @@ def show_prompt_string(style, show_git=True):
     if debian_chroot:
         PS1 += style('[{}] '.format(debian_chroot), fg=Color.BLUE, bold=True)
 
+    # If a Conda environment is active, show its prompt prefix (which already
+    # includes the parentheses and trailing space).
+    if 'CONDA_PROMPT_MODIFIER' in os.environ:
+        # Green like a snake!
+        PS1 += style(os.environ['CONDA_PROMPT_MODIFIER'], fg=Color.LIGHT_GREEN)
+
     # If we're inside a Python virtualenv, show the basename of the virtualenv
     # directory.  (Note: As of virtualenv v20.0.27, we can't support custom
     # virtualenv prompt prefixes, as virtualenv does not export the relevant