1 files changed, 205 insertions, 0 deletions
diff --git a/mwlib/sanitychecker.py b/mwlib/sanitychecker.py
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+++ b/mwlib/sanitychecker.py
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+# Copyright (c) 2007-2008 PediaPress GmbH
+# See README.txt for additional licensing information.
+"""
+class for defining DTD-Like Rules for the tree
+"""
+from advtree import Article
+
+from mwlib.log import Log
+log = Log("sanitychecker")
+
+# -----------------------------------------------------------
+# Constraints
+# -----------------------------------------------------------
+
+class ConstraintBase(object):
+    def __init__(self, *klasses):
+        self.klasses = klasses
+
+    def test(self, nodes): 
+        return True,None # passed
+
+    def __repr__(self):
+        return "%s(%s)" %(self.__class__.__name__, ", ".join(k.__name__ for k in self.klasses))
+
+
+class Forbid(ConstraintBase):
+    "forbid any of the classes"
+    def test(self, nodes): 
+        for n in nodes:
+            if n.__class__ in self.klasses:
+                return False, n
+        return True, None
+    
+
+class Allow(ConstraintBase):
+    "allow only these classes"
+    def test(self, nodes): 
+        for n in nodes:
+            if not n.__class__ in self.klasses:
+                return False, n
+        return True, None
+
+
+class Require(ConstraintBase):
+    "require any of these classes"
+    def test(self, nodes): 
+        for n in nodes:
+            if n.__class__ in self.klasses:
+                return True, n
+        return False, None
+  
+class Equal(ConstraintBase):
+    "node classes and their order must be equal to these klasses"
+    def test(self, nodes): 
+        if len(nodes) != len(self.klasses):
+            return False, None # FIXME what could we report?
+        for i,n in enumerate(nodes):
+            if n.__class__ !=  self.klasses[i]:
+                return False, n
+        return True, None
+    
+
+# -----------------------------------------------------------
+# Rules regarding [Children, AllChildren, Parents, ...]
+# -----------------------------------------------------------
+
+class RuleBase:
+    def __init__(self, klass, constraint):
+        self.klass = klass
+        self.constraint = constraint
+    
+    def _tocheck(self, node):
+       return [] 
+
+    def test(self, node):
+        if node.__class__ == self.klass:
+            return self.constraint.test( self._tocheck(node) )
+        return True, None
+
+    def __repr__(self):
+        return "%s(%s, %r)" %(self.__class__.__name__, self.klass.__name__, self.constraint)
+
+class ChildrenOf(RuleBase):
+    def _tocheck(self, node):
+        return node.children
+
+class AllChildrenOf(RuleBase):
+    def _tocheck(self, node):
+        return node.getAllChildren()
+
+class ParentsOf(RuleBase):
+    def _tocheck(self, node):
+        return node.parents
+
+class ParentOf(RuleBase):
+    def _tocheck(self, node):
+        if node.parent:
+            return [node.parent]
+        return []
+
+class SiblingsOf(RuleBase):
+    def _tocheck(self, node):
+        return node.siblings
+
+
+
+# example custom rules
+
+class RequireChild(RuleBase):
+
+    def __init__(self, klass):
+        self.klass = klass
+
+    def __repr__(self):
+        return "%s(%s)" %(self.__class__.__name__, self.klass.__name__)
+
+    def test(self, node):
+        if node.__class__ == self.klass:
+            if not len(node.children):
+                return False, node
+        return True, None
+
+
+
+
+# -----------------------------------------------------------
+# Callbacks
+# -----------------------------------------------------------
+"""
+callbacks get called if added to rules
+callback return values should be:
+ * True if it modified the tree and the sanity check needs to restart
+ * False if the tree is left unmodified
+"""
+class SanityException(Exception):
+    pass    
+
+def exceptioncb(rule, node=None, parentnode=None):
+    raise SanityException("%r  err:%r" %(rule, node or parentnode) )
+
+def warncb(rule, node=None, parentnode=None):
+    log.warn("%r node:%r parent:%r" %(rule, node, parentnode))
+    return False
+
+def removecb(rule, node=None, parentnode=None):
+    assert node and node.parent
+    node.parent.removeChild(node)
+    return True
+
+
+
+# -----------------------------------------------------------
+# Container for sanity rules
+# -----------------------------------------------------------
+
+class SanityChecker(object):
+
+    def __init__(self):
+        self.rules = []
+
+    def addRule(self, rule, actioncb=exceptioncb):
+        self.rules.append((rule, actioncb))
+    
+    def check(self, tree):
+        """ 
+        check each node with each rule
+        on failure call callback
+        """
+        modified = True
+        while modified:
+            modified = False
+            for node in tree.allchildren():
+                #if node.__class__ == Article:
+                #    log.info("checking article:", node.caption.encode('utf-8'))
+                for r,cb in self.rules:
+                    passed, errnode = r.test(node)
+                    if not passed and cb:
+                        if cb(r, errnode or node):
+                            modified = True
+                            break
+                if modified:
+                    break
+
+def demo(tree):
+    "for documentation only, see tests for more demos"
+    from mwlib.advtree import Table, Row, Cell, Text, ImageLink, PreFormatted
+
+    sc = SanityChecker()
+    rules = [ChildrenOf(Table, Allow(Row)),
+             ChildrenOf(Row, Allow(Cell)),
+             AllChildrenOf(Cell, Require(Text, ImageLink)),
+             AllChildrenOf(Cell, Forbid(PreFormatted)),
+             ChildrenOf(PreFormatted, Equal(Text)),
+             ]
+    
+    def mycb(rule, node=None, parentnode=None):
+        print "failed", rule, node or parentnode
+        modifiedtree = False
+        return modifiedtree
+
+    for r in rules:
+        sc.addRule( r, mycb)
+    #sc.check(anytree)
+    
+