GumTree Edit script computation

Author: cedricrupb

code_diff/__init__.py

@@ -85,13 +85,27 @@ def sstub_pattern(self):
         return classify_sstub(*diff_search(self.source_ast, self.target_ast))
 
     def edit_script(self):
-        return compute_edit_script(self.source_ast, self.target_ast)
+
+        source_ast, target_ast = self.source_ast, self.target_ast
+
+        def is_statement_type(node_type):
+            return any(match_type(r, node_type) for r in self.config.statement_types)
+
+        if not is_statement_type(source_ast.type) or not is_statement_type(target_ast.type):
+            # We need something where we can add to (root)
+            if source_ast.parent is not None:
+                source_ast = source_ast.parent
+            
+            if target_ast.parent is not None:
+                target_ast = target_ast.parent
+
+        return compute_edit_script(source_ast, target_ast)
 
     def __repr__(self):
         return "%s -> %s" % (self.source_text, self.target_text)
 
 
-    
+
 
 # AST Utils -----------------------------------------------------------
 

code_diff/ast.py

@@ -7,13 +7,14 @@
 
 class ASTNode(object):
 
-    def __init__(self, type, text = None, parent = None, children = None):
+    def __init__(self, type, text = None, position = None, parent = None, children = None):
 
         # Basic node attributes
         self.type = type
         self.children = children if children is not None else []
         self.parent   = parent
         self.text     = text   # If text is not None, then leaf node
+        self.position = position
 
         # Tree based attributes
         self.subtree_hash      = None
@@ -56,8 +57,8 @@ def __repr__(self):
         return "ASTNode(%s)" % (", ".join(["%s=%s" % (k, v) for k, v in attrs.items() if v is not None]))
 
 
-def default_create_node(type, children, text = None):
-    new_node = ASTNode(type, text = text, children = children)
+def default_create_node(type, children, text = None, position = None):
+    new_node = ASTNode(type, text = text, position = position, children = children)
 
     # Subtree metrics
     height = 1
@@ -101,7 +102,8 @@ def _create_node(self, ast_node, text = None):
         children = [self.node_index[_node_key(c)] for c in ast_node.children
                      if _node_key(c) in self.node_index]
 
-        current_node = self.create_node_fn(ast_node.type, children, text = text)
+        position = (ast_node.start_point, ast_node.end_point)
+        current_node = self.create_node_fn(ast_node.type, children, text = text, position = position)
         self.node_index[node_key] = current_node
 
         # Add parent if ready

code_diff/gumtree/__init__.py

@@ -1,15 +1,29 @@
-from .isomap  import gumtree_isomap
-from .editmap import gumtree_editmap
+from .isomap   import gumtree_isomap
+from .editmap  import gumtree_editmap
+from .chawathe import compute_chawathe_edit_script
+from .ops      import (Update, Insert, Delete, Move)
 
 # Edit script ----------------------------------------------------------------
 
-def compute_edit_script(source_ast, target_ast):
-    
-    isomap = gumtree_isomap(source_ast, target_ast)
-    print(isomap)
-    print("----------------------------------------------------------------")
+def compute_edit_script(source_ast, target_ast, min_height = 1):
+
+    # If source_ast and target_ast only leaves
+    if len(source_ast.children) == 0 and len(target_ast.children) == 0:
+        return [_update_leaf(source_ast, target_ast)]
+
+    isomap = gumtree_isomap(source_ast, target_ast, min_height)
+
+    while len(isomap) == 0 and min_height > 0:
+        min_height -= 1
+        isomap = gumtree_isomap(source_ast, target_ast, min_height)
 
     editmap = gumtree_editmap(isomap, source_ast, target_ast)
+    editscript = compute_chawathe_edit_script(editmap, source_ast, target_ast)
+    
+    return editscript
+    
+
+# Update leaf ----------------------------------------------------------------
 
-    print(editmap)
-    
+def _update_leaf(source_ast, target_ast):
+    return Update(source_ast, target_ast.text)