diff options
| -rw-r--r-- | portato/dependency.py | 55 |
1 files changed, 49 insertions, 6 deletions
diff --git a/portato/dependency.py b/portato/dependency.py index 1f1c5e1..9a8ff37 100644 --- a/portato/dependency.py +++ b/portato/dependency.py @@ -81,8 +81,17 @@ class DependencyTree (object): deps : set(`Dependency`) The list of dependencies which are not dependent on a useflag. - flags : string -> `DependencyTree` + flags : string -> `UseDependency` Holds the additional dependency trees per useflag. + + ors : list(`OrDependency`) + A list of dependency trees, which are or'ed. + + subs : list(`DependencyTree`) + A list of subtrees. + + empty : boolean + Is this tree empty? """ def __init__ (self): @@ -115,17 +124,29 @@ class DependencyTree (object): self.deps.add(Dependency(dep)) def add_or (self): + """ + Adds an `OrDependency` and returns the created tree. + + :rtype: `OrDependency` + """ o = OrDependency() self._ors.append(o) return o def add_sub (self): + """ + Adds and returns a subtree. + + :rtype: `DependencyTree` + """ + + # a normal DepTree does not handle subtrees - so return self + # this is intended to be overwritten by subclasses return self def add_flag (self, flag): """ - Adds a new useflag to this tree. - For convenience the newly created sub-tree is returned. + Adds a new useflag to this tree and returns the created sub-tree. :param flag: the new flag :rtype: `DependencyTree` @@ -134,8 +155,14 @@ class DependencyTree (object): return self.flags[flag] # it's a defaultdict def parse (self, deps): + """ + Parses the list of dependencies, as it is returned by paren_reduce, and fills the tree. + """ + it = iter(deps) for dep in it: + + # use if dep[-1] == "?": ntree = self.add_flag(dep[:-1]) n = it.next() @@ -143,6 +170,7 @@ class DependencyTree (object): n = [n] ntree.parse(n) + # or elif dep == "||": n = it.next() # skip if not hasattr(n, "__iter__"): @@ -150,13 +178,22 @@ class DependencyTree (object): self.add_or().parse(n) + # sub elif isinstance(dep, list): self.add_sub().parse(dep) + # normal else: self.add(dep) - def get_list(self, l): + def get_non_empty(self, l): + """ + Convenience accessor method. Returns these elements of a list, which are non-empty. + This also removes the empty ones from the list. + + :param l: a list :) + :rtype: iter + """ for d in l[:]: if d.is_empty(): l.remove(d) @@ -164,19 +201,25 @@ class DependencyTree (object): yield d def get_ors (self): - return self.get_list(self._ors) + return self.get_non_empty(self._ors) def get_subs (self): - return self.get_list(self._subs) + return self.get_non_empty(self._subs) ors = property(get_ors) subs = property(get_subs) class OrDependency (DependencyTree): + """ + Models an or-dependency. This only overwrites `add_sub`, as sublists have a special meaning here. + """ def add_sub (self): s = DependencyTree() self._subs.append(s) return s class UseDependency (DependencyTree): + """ + Models an use-dependency. Nothing is overwritten. + """ pass |