#------------------------------------------------------------------------------
# Copyright (c) 2013, Nucleic Development Team.
#
# Distributed under the terms of the Modified BSD License.
#
# The full license is in the file LICENSE, distributed with this software.
#------------------------------------------------------------------------------
import linecache
import traceback
from types import ModuleType
from atom.api import Atom, Str, Typed, observe
import enaml
from enaml.core.object import Object
from enaml.core.enaml_compiler import EnamlCompiler
from enaml.core.parser import parse
from enaml.widgets.widget import Widget
try:
import jedi
COMPLETION_AVAILABLE = True
except ImportError:
COMPLETION_AVAILABLE = False
ENAML_KEYWORDS = ['enamldef', 'attr', 'alias', 'func', 'template', 'class',
'with', 'else', 'while']
def _fake_linecache(text, filename):
""" Inject text into the linecache for traceback purposes.
Parameters
----------
text : str
The text of the file.
filename : str
The name of the file.
"""
size = len(text)
mtime = int(1343290295)
lines = text.splitlines()
lines = [l + '\n' for l in lines]
linecache.cache[filename] = size, mtime, lines, filename
[docs]
class LiveEditorModel(Atom):
""" A model which works in concert with the live editor panels.
This model manages the compiling and instantiation of the model
and view objects defined by the user.
The model has six inputs:
'model_text'
The full text of the Python module which defines the model.
'view_text'
The full text of the Enaml module which defines the view.
'model_item'
The name of the target model class in the model module.
'view_item'
The name of the target enamldef in the view module.
'model_filename'
An optional filename to associate with the model module.
'view_filename'
An optional filename to associate with the view module.
The model has three outputs:
'compiled_model'
The instance of the user defined model, or None if no model
could be created.
'compiled_view'
The instance of the user defined view, or None if no view
could be created.
'traceback'
A string holding the traceback for any compilation and
instantiation errors.
If the 'compiled_view' object has a 'model' attribute, then the
'compiled_model' object will be assigned to that attribute.
"""
#: The current live model object bound to the main view.
compiled_model = Typed(Atom)
#: The current live view object to include in the main view.
compiled_view = Typed(Object)
#: The Python module input text for the model module.
model_text = Str()
#: The Enaml module input text for the view module.
view_text = Str()
#: The string name of the Atom class to use as the model.
model_item = Str()
#: The string name of the enamldef to use as the view.
view_item = Str()
#: An optional filename to use when compiling the python code.
model_filename = Str('__live_model__.py')
#: An optional filename to use when compiling the enaml code.
view_filename = Str('__live_view__.enaml')
#: A string which holds the most recent traceback.
traceback = Str()
#: The module created from the model text.
_model_module = Typed(ModuleType)
#: The module created from the view text.
_view_module = Typed(ModuleType)
#--------------------------------------------------------------------------
# Post Validators
#--------------------------------------------------------------------------
def _post_validate_model_text(self, old, new):
""" Post validate the model text.
This validator replaces CRLF with LF characters.
"""
return new.replace('\r\n', '\n').replace('\r', '\n')
def _post_validate_view_text(self, old, new):
""" Post validate the view text.
This validator replaces CRLF with LF characters.
"""
return new.replace('\r\n', '\n').replace('\r', '\n')
#--------------------------------------------------------------------------
# Observers
#--------------------------------------------------------------------------
@observe('model_text', 'model_item')
def _refresh_model_trigger(self, change):
""" An observer which triggers a compiled model refresh.
"""
if change['type'] == 'update':
self.refresh_model()
@observe('view_text', 'view_item')
def _refresh_view_trigger(self, change):
""" An observer which triggers a compiled view refresh.
"""
if change['type'] == 'update':
self.refresh_view()
#--------------------------------------------------------------------------
# Public API
#--------------------------------------------------------------------------
[docs]
def refresh_model(self):
""" Refresh the compiled model object.
This method will (re)compile the model for the given model text
and update the 'compiled_model' attribute. If a compiled view is
available and has a member named 'model', the model will be
applied to the view.
"""
text = self.model_text
filename = self.model_filename
_fake_linecache(text, filename)
try:
if not text:
self.compiled_model = None
self._model_module = None
else:
code = compile(text, filename, 'exec')
module = ModuleType(filename.rsplit('.', 1)[0])
module.__file__ = filename
namespace = module.__dict__
exec(code, namespace)
model = namespace.get(self.model_item, lambda: None)()
self.compiled_model = model
self._model_module = module
self.relink_view()
except Exception:
self.traceback = traceback.format_exc()
else:
self.traceback = ''
[docs]
def refresh_view(self):
""" Refresh the compiled view object.
This method will (re)compile the view for the given view text
and update the 'compiled_view' attribute. If a compiled model
is available and the view has a member named 'model', the model
will be applied to the view.
"""
text = self.view_text
filename = self.view_filename
_fake_linecache(text, filename)
try:
if not text:
self.compiled_view = None
self._view_module = None
else:
ast = parse(text, filename=filename)
code = EnamlCompiler.compile(ast, filename)
module = ModuleType('__main__')
module.__file__ = filename
namespace = module.__dict__
with enaml.imports():
exec(code, namespace)
view = namespace.get(self.view_item, lambda: None)()
if isinstance(view, Object) and 'model' in view.members():
view.model = self.compiled_model
# trap any initialization errors and roll back the view
old = self.compiled_view
try:
self.compiled_view = view
except Exception:
self.compiled_view = old
if isinstance(old, Widget):
old.show()
raise
self._view_module = module
if old is not None and not old.is_destroyed:
old.destroy()
except Exception:
self.traceback = traceback.format_exc()
else:
self.traceback = ''
[docs]
def autocomplete(self, source, position):
""" Obtain autocompletion suggestions for the source text using jedi .
if available.
"""
if not COMPLETION_AVAILABLE or not source:
return ENAML_KEYWORDS
try:
# Use jedi to get suggestions
line, column = position
script = jedi.Script(source, line+1, column)
# Get suggestions
results = []
for c in script.completions():
results.append(c.name)
# Try to get a signature if the docstring matches
# something Scintilla will use (ex "func(..." or "Class(...")
# Scintilla ignores docstrings without a comma in the args
if c.type in ['function', 'class', 'instance']:
docstring = c.docstring()
if docstring.startswith("{}(".format(c.name)):
results.append(docstring)
continue
return results + ENAML_KEYWORDS
except Exception:
# Autocompletion may fail for random reasons so catch all errors
# as we don't want the editor to quit because of this
return ENAML_KEYWORDS
[docs]
def relink_view(self):
""" Relink the compiled view with the compiled model.
"""
view = self.compiled_view
if view is not None and 'model' in view.members():
view.model = self.compiled_model