dirstack skeleton

xonsh/aliases.py

@@ -4,6 +4,7 @@ import os
 import platform
 import builtins
 import subprocess
+from argparse import ArgumentParser
 
 def cd(args, stdin=None):
     """Changes the directory.
@@ -25,6 +26,18 @@ def cd(args, stdin=None):
     builtins.__xonsh_env__['PWD'] = os.getcwd()
     return None, None
 
+pushd_parser = ArgumentParser(description="pushd: push onto the directory stack")
+def pushd(args, stdin=None):
+    return None, None
+
+popd_parser = ArgumentParser(description="popd: pop from the directory stack")
+def popd(args, stdin=None):
+    return None, None
+
+dirs_parser = ArgumentParser(description="dirs: view and manipulate the directory stack")
+def dirs(args, stdin=None):
+    return None, None
+
 def exit(args, stdin=None):
     """Sends signal to exit shell."""
     builtins.__xonsh_exit__ = True
@@ -57,6 +70,9 @@ def source_bash(args, stdin=None):
 
 DEFAULT_ALIASES = {
     'cd': cd,
+    'pushd':pushd,
+    'popd':popd,
+    'dirs':dirs,
     'EOF': exit,
     'exit': exit,
     'source-bash': source_bash,

xonsh/environ.py

@@ -93,6 +93,7 @@ def multiline_prompt():
 
 BASE_ENV = {
     'INDENT': '    ',
+    'XONSH_DIRSTACK': None,
     'PROMPT': default_prompt,
     'MULTILINE_PROMPT': '.',
     'XONSHRC': os.path.expanduser('~/.xonshrc'),
@@ -149,6 +150,8 @@ def default_env(env=None):
     """Constructs a default xonsh environment."""
     # in order of increasing precedence
     ctx = dict(BASE_ENV)
+    if ctx.get('XONSH_DIRSTACK',None) is None:
+        ctx['XONSH_DIRSTACK'] = []
     ctx.update(os.environ)
     ctx.update(bash_env())
     if env is not None: