DOTFILES/dot_config/private_fish/functions/__bass.py

141 lines
4.0 KiB
Python

"""
To be used with a companion fish function like this:
function refish
set -l _x (python /tmp/bass.py source ~/.nvm/nvim.sh ';' nvm use iojs); source $_x; and rm -f $_x
end
"""
from __future__ import print_function
import json
import os
import signal
import subprocess
import sys
import traceback
BASH = 'bash'
FISH_READONLY = [
'PWD', 'SHLVL', 'history', 'pipestatus', 'status', 'version',
'FISH_VERSION', 'fish_pid', 'hostname', '_', 'fish_private_mode'
]
IGNORED = [
'PS1', 'XPC_SERVICE_NAME'
]
def ignored(name):
if name == 'PWD': # this is read only, but has special handling
return False
# ignore other read only variables
if name in FISH_READONLY:
return True
if name in IGNORED or name.startswith("BASH_FUNC"):
return True
if name.startswith('%'):
return True
return False
def escape(string):
# use json.dumps to reliably escape quotes and backslashes
return json.dumps(string).replace(r'$', r'\$')
def escape_identifier(word):
return escape(word.replace('?', '\\?'))
def comment(string):
return '\n'.join(['# ' + line for line in string.split('\n')])
def gen_script():
# Use the following instead of /usr/bin/env to read environment so we can
# deal with multi-line environment variables (and other odd cases).
env_reader = "%s -c 'import os,json; print(json.dumps({k:v for k,v in os.environ.items()}))'" % (sys.executable)
args = [BASH, '-c', env_reader]
output = subprocess.check_output(args, universal_newlines=True)
old_env = output.strip()
pipe_r, pipe_w = os.pipe()
if sys.version_info >= (3, 4):
os.set_inheritable(pipe_w, True)
command = 'eval $1 && ({}; alias) >&{}'.format(
env_reader,
pipe_w
)
args = [BASH, '-c', command, 'bass', ' '.join(sys.argv[1:])]
p = subprocess.Popen(args, universal_newlines=True, close_fds=False)
os.close(pipe_w)
with os.fdopen(pipe_r) as f:
new_env = f.readline()
alias_str = f.read()
if p.wait() != 0:
raise subprocess.CalledProcessError(
returncode=p.returncode,
cmd=' '.join(sys.argv[1:]),
output=new_env + alias_str
)
new_env = new_env.strip()
old_env = json.loads(old_env)
new_env = json.loads(new_env)
script_lines = []
for k, v in new_env.items():
if ignored(k):
continue
v1 = old_env.get(k)
if not v1:
script_lines.append(comment('adding %s=%s' % (k, v)))
elif v1 != v:
script_lines.append(comment('updating %s=%s -> %s' % (k, v1, v)))
# process special variables
if k == 'PWD':
script_lines.append('cd %s' % escape(v))
continue
else:
continue
if k == 'PATH':
value = ' '.join([escape(directory)
for directory in v.split(':')])
else:
value = escape(v)
script_lines.append('set -g -x %s %s' % (k, value))
for var in set(old_env.keys()) - set(new_env.keys()):
script_lines.append(comment('removing %s' % var))
script_lines.append('set -e %s' % var)
script = '\n'.join(script_lines)
alias_lines = []
for line in alias_str.splitlines():
_, rest = line.split(None, 1)
k, v = rest.split("=", 1)
alias_lines.append("alias " + escape_identifier(k) + "=" + v)
alias = '\n'.join(alias_lines)
return script + '\n' + alias
script_file = os.fdopen(3, 'w')
if not sys.argv[1:]:
print('__bass_usage', file=script_file, end='')
sys.exit(0)
try:
script = gen_script()
except subprocess.CalledProcessError as e:
sys.exit(e.returncode)
except Exception:
print('Bass internal error!', file=sys.stderr)
raise # traceback will output to stderr
except KeyboardInterrupt:
signal.signal(signal.SIGINT, signal.SIG_DFL)
os.kill(os.getpid(), signal.SIGINT)
else:
script_file.write(script)