Fix crash when bash is not found on Windows. Also, look up GitForWindows (e.g. MSYS bash) if bash is not on PATH.

xonsh/completers/bash.py

@@ -34,6 +34,12 @@ for ((i=0;i<${{#COMPREPLY[*]}};i++)) do echo ${{COMPREPLY[i]}}; done
 """
 
 
+if ON_WINDOWS:
+    from xonsh.platform import WINDOWS_BASH_COMMAND as BASH_COMMAND
+else: 
+    BASH_COMMAND = 'bash'
+
+
 def update_bash_completion():
     global BASH_COMPLETE_FUNCS, BASH_COMPLETE_FILES, BASH_COMPLETE_HASH
     global CACHED_FUNCS, CACHED_FILES, CACHED_HASH, INITED
@@ -108,9 +114,9 @@ def complete_from_bash(prefix, line, begidx, endidx, ctx):
         end=endidx + 1, prefix=prefix, prev=shlex.quote(prev))
     try:
         out = subprocess.check_output(
-            ['bash'], input=script, universal_newlines=True,
+            [BASH_COMMAND], input=script, universal_newlines=True,
             stderr=subprocess.PIPE, env=builtins.__xonsh_env__.detype())
-    except subprocess.CalledProcessError:
+    except (subprocess.CalledProcessError, FileNotFoundError):
         out = ''
 
     rtn = set(out.splitlines())
@@ -161,11 +167,15 @@ def _load_bash_complete_files():
 
 
 def _source_completions(source):
-    return subprocess.check_output(
-            ['bash'], input='\n'.join(source), universal_newlines=True,
+    try:
+        import pdb; pdb.set_trace()
+        return subprocess.check_output(
+            [BASH_COMMAND], input='\n'.join(source), universal_newlines=True,
             env=builtins.__xonsh_env__.detype(), stderr=subprocess.DEVNULL)
+    except FileNotFoundError:
+        return ''
 
-
+        
 def _collect_completions_sources():
     sources = []
     completers = builtins.__xonsh_env__.get('BASH_COMPLETIONS', ())

xonsh/platform.py

@@ -188,7 +188,31 @@ if ON_WINDOWS:
 else:
     win_unicode_console = None
 
+    
+if ON_WINDOWS:
+    import winreg
+    try: 
+        key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, 'SOFTWARE\\GitForWindows')
+        GIT_FOR_WINDOWS_PATH, type = winreg.QueryValueEx(key, "InstallPath")
+    except FileNotFoundError:    
+        GIT_FOR_WINDOWS_PATH = None
 
+
+
+if ON_WINDOWS:
+    # Check that bash in on path otherwise try the default bin directory 
+    # used by Git for windows
+    import subprocess
+    WINDOWS_BASH_COMMAND = 'bash'
+    try: 
+        subprocess.check_call([WINDOWS_BASH_COMMAND,'--version'])
+    except FileNotFoundError:
+        if GIT_FOR_WINDOWS_PATH: 
+            bashcmd = os.path.join(GIT_FOR_WINDOWS_PATH, 'bin\\bash.exe')
+            if os.path.isfile(bashcmd):
+                WINDOWS_BASH_COMMAND = bashcmd
+
+            
 #
 # Bash completions defaults
 #
@@ -210,13 +234,13 @@ elif ON_DARWIN:
     BASH_COMPLETIONS_DEFAULT = (
         '/usr/local/etc/bash_completion',
         '/opt/local/etc/profile.d/bash_completion.sh')
-elif ON_WINDOWS:
-    progamfiles = os.environ.get('PROGRAMFILES', 'C:/Program Files')
+elif ON_WINDOWS and GIT_FOR_WINDOWS_PATH:
     BASH_COMPLETIONS_DEFAULT = (
-        progamfiles + '/Git/usr/share/bash-completion',
-        progamfiles + '/Git/usr/share/bash-completion/completions',
-        progamfiles + '/Git/mingw64/share/git/completion/git-completion.bash')
+        os.path.join(GIT_FOR_WINDOWS_PATH, 'usr\\share\\bash-completion'),
+        os.path.join(GIT_FOR_WINDOWS_PATH, 'usr\\share\\bash-completion\\completions'),
+        os.path.join(GIT_FOR_WINDOWS_PATH, 'mingw64\\share\\git\\completion\\git-completion.bash'))
 
+        
 #
 # All constants as a dict
 #