lazy load pygments lib so we can use VCS without it installed

rhodecode/lib/vcs/nodes.py

@@ -1,618 +1,616 b''
 # -*- coding: utf-8 -*-
 """
     vcs.nodes
     ~~~~~~~~~
 
     Module holding everything related to vcs nodes.
 
     :created_on: Apr 8, 2010
     :copyright: (c) 2010-2011 by Marcin Kuzminski, Lukasz Balcerzak.
 """
 import os
 import stat
 import posixpath
 import mimetypes
 
-from pygments import lexers
-
 from rhodecode.lib.vcs.backends.base import EmptyChangeset
 from rhodecode.lib.vcs.exceptions import NodeError, RemovedFileNodeError
 from rhodecode.lib.vcs.utils.lazy import LazyProperty
 from rhodecode.lib.vcs.utils import safe_unicode
 
 
 class NodeKind:
     SUBMODULE = -1
     DIR = 1
     FILE = 2
 
 
 class NodeState:
     ADDED = u'added'
     CHANGED = u'changed'
     NOT_CHANGED = u'not changed'
     REMOVED = u'removed'
 
 
 class NodeGeneratorBase(object):
     """
     Base class for removed added and changed filenodes, it's a lazy generator
     class that will create filenodes only on iteration or call
 
     The len method doesn't need to create filenodes at all
     """
 
     def __init__(self, current_paths, cs):
         self.cs = cs
         self.current_paths = current_paths
 
     def __call__(self):
         return [n for n in self]
 
     def __getslice__(self, i, j):
         for p in self.current_paths[i:j]:
             yield self.cs.get_node(p)
 
     def __len__(self):
         return len(self.current_paths)
 
     def __iter__(self):
         for p in self.current_paths:
             yield self.cs.get_node(p)
 
 
 class AddedFileNodesGenerator(NodeGeneratorBase):
     """
     Class holding Added files for current changeset
     """
     pass
 
 
 class ChangedFileNodesGenerator(NodeGeneratorBase):
     """
     Class holding Changed files for current changeset
     """
     pass
 
 
 class RemovedFileNodesGenerator(NodeGeneratorBase):
     """
     Class holding removed files for current changeset
     """
     def __iter__(self):
         for p in self.current_paths:
             yield RemovedFileNode(path=p)
 
     def __getslice__(self, i, j):
         for p in self.current_paths[i:j]:
             yield RemovedFileNode(path=p)
 
 
 class Node(object):
     """
     Simplest class representing file or directory on repository.  SCM backends
     should use ``FileNode`` and ``DirNode`` subclasses rather than ``Node``
     directly.
 
     Node's ``path`` cannot start with slash as we operate on *relative* paths
     only. Moreover, every single node is identified by the ``path`` attribute,
     so it cannot end with slash, too. Otherwise, path could lead to mistakes.
     """
 
     def __init__(self, path, kind):
         if path.startswith('/'):
             raise NodeError("Cannot initialize Node objects with slash at "
                 "the beginning as only relative paths are supported")
         self.path = path.rstrip('/')
         if path == '' and kind != NodeKind.DIR:
             raise NodeError("Only DirNode and its subclasses may be "
                             "initialized with empty path")
         self.kind = kind
         #self.dirs, self.files = [], []
         if self.is_root() and not self.is_dir():
             raise NodeError("Root node cannot be FILE kind")
 
     @LazyProperty
     def parent(self):
         parent_path = self.get_parent_path()
         if parent_path:
             if self.changeset:
                 return self.changeset.get_node(parent_path)
             return DirNode(parent_path)
         return None
 
     @LazyProperty
     def unicode_path(self):
         return safe_unicode(self.path)
 
     @LazyProperty
     def name(self):
         """
         Returns name of the node so if its path
         then only last part is returned.
         """
         return safe_unicode(self.path.rstrip('/').split('/')[-1])
 
     def _get_kind(self):
         return self._kind
 
     def _set_kind(self, kind):
         if hasattr(self, '_kind'):
             raise NodeError("Cannot change node's kind")
         else:
             self._kind = kind
             # Post setter check (path's trailing slash)
             if self.path.endswith('/'):
                 raise NodeError("Node's path cannot end with slash")
 
     kind = property(_get_kind, _set_kind)
 
     def __cmp__(self, other):
         """
         Comparator using name of the node, needed for quick list sorting.
         """
         kind_cmp = cmp(self.kind, other.kind)
         if kind_cmp:
             return kind_cmp
         return cmp(self.name, other.name)
 
     def __eq__(self, other):
         for attr in ['name', 'path', 'kind']:
             if getattr(self, attr) != getattr(other, attr):
                 return False
         if self.is_file():
             if self.content != other.content:
                 return False
         else:
             # For DirNode's check without entering each dir
             self_nodes_paths = list(sorted(n.path for n in self.nodes))
             other_nodes_paths = list(sorted(n.path for n in self.nodes))
             if self_nodes_paths != other_nodes_paths:
                 return False
         return True
 
     def __nq__(self, other):
         return not self.__eq__(other)
 
     def __repr__(self):
         return '<%s %r>' % (self.__class__.__name__, self.path)
 
     def __str__(self):
         return self.__repr__()
 
     def __unicode__(self):
         return self.name
 
     def get_parent_path(self):
         """
         Returns node's parent path or empty string if node is root.
         """
         if self.is_root():
             return ''
         return posixpath.dirname(self.path.rstrip('/')) + '/'
 
     def is_file(self):
         """
         Returns ``True`` if node's kind is ``NodeKind.FILE``, ``False``
         otherwise.
         """
         return self.kind == NodeKind.FILE
 
     def is_dir(self):
         """
         Returns ``True`` if node's kind is ``NodeKind.DIR``, ``False``
         otherwise.
         """
         return self.kind == NodeKind.DIR
 
     def is_root(self):
         """
         Returns ``True`` if node is a root node and ``False`` otherwise.
         """
         return self.kind == NodeKind.DIR and self.path == ''
 
     def is_submodule(self):
         """
         Returns ``True`` if node's kind is ``NodeKind.SUBMODULE``, ``False``
         otherwise.
         """
         return self.kind == NodeKind.SUBMODULE
 
     @LazyProperty
     def added(self):
         return self.state is NodeState.ADDED
 
     @LazyProperty
     def changed(self):
         return self.state is NodeState.CHANGED
 
     @LazyProperty
     def not_changed(self):
         return self.state is NodeState.NOT_CHANGED
 
     @LazyProperty
     def removed(self):
         return self.state is NodeState.REMOVED
 
 
 class FileNode(Node):
     """
     Class representing file nodes.
 
     :attribute: path: path to the node, relative to repostiory's root
     :attribute: content: if given arbitrary sets content of the file
     :attribute: changeset: if given, first time content is accessed, callback
     :attribute: mode: octal stat mode for a node. Default is 0100644.
     """
 
     def __init__(self, path, content=None, changeset=None, mode=None):
         """
         Only one of ``content`` and ``changeset`` may be given. Passing both
         would raise ``NodeError`` exception.
 
         :param path: relative path to the node
         :param content: content may be passed to constructor
         :param changeset: if given, will use it to lazily fetch content
         :param mode: octal representation of ST_MODE (i.e. 0100644)
         """
 
         if content and changeset:
             raise NodeError("Cannot use both content and changeset")
         super(FileNode, self).__init__(path, kind=NodeKind.FILE)
         self.changeset = changeset
         self._content = content
         self._mode = mode or 0100644
 
     @LazyProperty
     def mode(self):
         """
         Returns lazily mode of the FileNode. If ``changeset`` is not set, would
         use value given at initialization or 0100644 (default).
         """
         if self.changeset:
             mode = self.changeset.get_file_mode(self.path)
         else:
             mode = self._mode
         return mode
 
     def _get_content(self):
         if self.changeset:
             content = self.changeset.get_file_content(self.path)
         else:
             content = self._content
         return content
 
     @property
     def content(self):
         """
         Returns lazily content of the FileNode. If possible, would try to
         decode content from UTF-8.
         """
         content = self._get_content()
 
         if bool(content and '\0' in content):
             return content
         return safe_unicode(content)
 
     @LazyProperty
     def size(self):
         if self.changeset:
             return self.changeset.get_file_size(self.path)
         raise NodeError("Cannot retrieve size of the file without related "
             "changeset attribute")
 
     @LazyProperty
     def message(self):
         if self.changeset:
             return self.last_changeset.message
         raise NodeError("Cannot retrieve message of the file without related "
             "changeset attribute")
 
     @LazyProperty
     def last_changeset(self):
         if self.changeset:
             return self.changeset.get_file_changeset(self.path)
         raise NodeError("Cannot retrieve last changeset of the file without "
             "related changeset attribute")
 
     def get_mimetype(self):
         """
         Mimetype is calculated based on the file's content. If ``_mimetype``
         attribute is available, it will be returned (backends which store
         mimetypes or can easily recognize them, should set this private
         attribute to indicate that type should *NOT* be calculated).
         """
         if hasattr(self, '_mimetype'):
             if (isinstance(self._mimetype, (tuple, list,)) and
                 len(self._mimetype) == 2):
                 return self._mimetype
             else:
                 raise NodeError('given _mimetype attribute must be an 2 '
                                'element list or tuple')
 
         mtype, encoding = mimetypes.guess_type(self.name)
 
         if mtype is None:
             if self.is_binary:
                 mtype = 'application/octet-stream'
                 encoding = None
             else:
                 mtype = 'text/plain'
                 encoding = None
         return mtype, encoding
 
     @LazyProperty
     def mimetype(self):
         """
         Wrapper around full mimetype info. It returns only type of fetched
         mimetype without the encoding part. use get_mimetype function to fetch
         full set of (type,encoding)
         """
         return self.get_mimetype()[0]
 
     @LazyProperty
     def mimetype_main(self):
         return self.mimetype.split('/')[0]
 
     @LazyProperty
     def lexer(self):
         """
         Returns pygment's lexer class. Would try to guess lexer taking file's
         content, name and mimetype.
         """
-
+        from pygments import lexers
         try:
             lexer = lexers.guess_lexer_for_filename(self.name, self.content, stripnl=False)
         except lexers.ClassNotFound:
             lexer = lexers.TextLexer(stripnl=False)
         # returns first alias
         return lexer
 
     @LazyProperty
     def lexer_alias(self):
         """
         Returns first alias of the lexer guessed for this file.
         """
         return self.lexer.aliases[0]
 
     @LazyProperty
     def history(self):
         """
         Returns a list of changeset for this file in which the file was changed
         """
         if self.changeset is None:
             raise NodeError('Unable to get changeset for this FileNode')
         return self.changeset.get_file_history(self.path)
 
     @LazyProperty
     def annotate(self):
         """
         Returns a list of three element tuples with lineno,changeset and line
         """
         if self.changeset is None:
             raise NodeError('Unable to get changeset for this FileNode')
         return self.changeset.get_file_annotate(self.path)
 
     @LazyProperty
     def state(self):
         if not self.changeset:
             raise NodeError("Cannot check state of the node if it's not "
                 "linked with changeset")
         elif self.path in (node.path for node in self.changeset.added):
             return NodeState.ADDED
         elif self.path in (node.path for node in self.changeset.changed):
             return NodeState.CHANGED
         else:
             return NodeState.NOT_CHANGED
 
     @property
     def is_binary(self):
         """
         Returns True if file has binary content.
         """
         _bin = '\0' in self._get_content()
         return _bin
 
     @LazyProperty
     def extension(self):
         """Returns filenode extension"""
         return self.name.split('.')[-1]
 
     @property
     def is_executable(self):
         """
         Returns ``True`` if file has executable flag turned on.
         """
         return bool(self.mode & stat.S_IXUSR)
 
     def __repr__(self):
         return '<%s %r @ %s>' % (self.__class__.__name__, self.path,
                                  getattr(self.changeset, 'short_id', ''))
 
 
 class RemovedFileNode(FileNode):
     """
     Dummy FileNode class - trying to access any public attribute except path,
     name, kind or state (or methods/attributes checking those two) would raise
     RemovedFileNodeError.
     """
     ALLOWED_ATTRIBUTES = [
         'name', 'path', 'state', 'is_root', 'is_file', 'is_dir', 'kind',
         'added', 'changed', 'not_changed', 'removed'
     ]
 
     def __init__(self, path):
         """
         :param path: relative path to the node
         """
         super(RemovedFileNode, self).__init__(path=path)
 
     def __getattribute__(self, attr):
         if attr.startswith('_') or attr in RemovedFileNode.ALLOWED_ATTRIBUTES:
             return super(RemovedFileNode, self).__getattribute__(attr)
         raise RemovedFileNodeError("Cannot access attribute %s on "
             "RemovedFileNode" % attr)
 
     @LazyProperty
     def state(self):
         return NodeState.REMOVED
 
 
 class DirNode(Node):
     """
     DirNode stores list of files and directories within this node.
     Nodes may be used standalone but within repository context they
     lazily fetch data within same repositorty's changeset.
     """
 
     def __init__(self, path, nodes=(), changeset=None):
         """
         Only one of ``nodes`` and ``changeset`` may be given. Passing both
         would raise ``NodeError`` exception.
 
         :param path: relative path to the node
         :param nodes: content may be passed to constructor
         :param changeset: if given, will use it to lazily fetch content
         :param size: always 0 for ``DirNode``
         """
         if nodes and changeset:
             raise NodeError("Cannot use both nodes and changeset")
         super(DirNode, self).__init__(path, NodeKind.DIR)
         self.changeset = changeset
         self._nodes = nodes
 
     @LazyProperty
     def content(self):
         raise NodeError("%s represents a dir and has no ``content`` attribute"
             % self)
 
     @LazyProperty
     def nodes(self):
         if self.changeset:
             nodes = self.changeset.get_nodes(self.path)
         else:
             nodes = self._nodes
         self._nodes_dict = dict((node.path, node) for node in nodes)
         return sorted(nodes)
 
     @LazyProperty
     def files(self):
         return sorted((node for node in self.nodes if node.is_file()))
 
     @LazyProperty
     def dirs(self):
         return sorted((node for node in self.nodes if node.is_dir()))
 
     def __iter__(self):
         for node in self.nodes:
             yield node
 
     def get_node(self, path):
         """
         Returns node from within this particular ``DirNode``, so it is now
         allowed to fetch, i.e. node located at 'docs/api/index.rst' from node
         'docs'. In order to access deeper nodes one must fetch nodes between
         them first - this would work::
 
            docs = root.get_node('docs')
            docs.get_node('api').get_node('index.rst')
 
         :param: path - relative to the current node
 
         .. note::
            To access lazily (as in example above) node have to be initialized
            with related changeset object - without it node is out of
            context and may know nothing about anything else than nearest
            (located at same level) nodes.
         """
         try:
             path = path.rstrip('/')
             if path == '':
                 raise NodeError("Cannot retrieve node without path")
             self.nodes  # access nodes first in order to set _nodes_dict
             paths = path.split('/')
             if len(paths) == 1:
                 if not self.is_root():
                     path = '/'.join((self.path, paths[0]))
                 else:
                     path = paths[0]
                 return self._nodes_dict[path]
             elif len(paths) > 1:
                 if self.changeset is None:
                     raise NodeError("Cannot access deeper "
                                     "nodes without changeset")
                 else:
                     path1, path2 = paths[0], '/'.join(paths[1:])
                     return self.get_node(path1).get_node(path2)
             else:
                 raise KeyError
         except KeyError:
             raise NodeError("Node does not exist at %s" % path)
 
     @LazyProperty
     def state(self):
         raise NodeError("Cannot access state of DirNode")
 
     @LazyProperty
     def size(self):
         size = 0
         for root, dirs, files in self.changeset.walk(self.path):
             for f in files:
                 size += f.size
 
         return size
 
     def __repr__(self):
         return '<%s %r @ %s>' % (self.__class__.__name__, self.path,
                                  getattr(self.changeset, 'short_id', ''))
 
 
 class RootNode(DirNode):
     """
     DirNode being the root node of the repository.
     """
 
     def __init__(self, nodes=(), changeset=None):
         super(RootNode, self).__init__(path='', nodes=nodes,
             changeset=changeset)
 
     def __repr__(self):
         return '<%s>' % self.__class__.__name__
 
 
 class SubModuleNode(Node):
     """
     represents a SubModule of Git or SubRepo of Mercurial
     """
     is_binary = False
     size = 0
 
     def __init__(self, name, url=None, changeset=None, alias=None):
         self.path = name
         self.kind = NodeKind.SUBMODULE
         self.alias = alias
         # we have to use emptyChangeset here since this can point to svn/git/hg
         # submodules we cannot get from repository
         self.changeset = EmptyChangeset(str(changeset), alias=alias)
         self.url = url or self._extract_submodule_url()
 
     def __repr__(self):
         return '<%s %r @ %s>' % (self.__class__.__name__, self.path,
                                  getattr(self.changeset, 'short_id', ''))
 
     def _extract_submodule_url(self):
         if self.alias == 'git':
             #TODO: find a way to parse gits submodule file and extract the
             # linking URL
             return self.path
         if self.alias == 'hg':
             return self.path
 
     @LazyProperty
     def name(self):
         """
         Returns name of the node so if its path
         then only last part is returned.
         """
         org = safe_unicode(self.path.rstrip('/').split('/')[-1])
         return u'%s @ %s' % (org, self.changeset.short_id)