visit() now returns paths in depth-first order. fixes issue #47

--HG--
branch : trunk

py/path/common.py

@@ -278,20 +278,20 @@ newline will be removed from the end of each line. """
         if rec: 
             if isinstance(rec, str):
                 rec = fnmatch(fil)
-            elif not py.builtin.callable(rec): 
+            elif not hasattr(rec, '__call__'):
-                rec = lambda x: True 
+                rec = None
-        reclist = [self]
-        while reclist: 
-            current = reclist.pop(0)
         try:
-                dirlist = current.listdir() 
+            entries = self.listdir()
         except ignore:
             return
-            for p in dirlist:
+        dirs = [p for p in entries 
+                    if p.check(dir=1) and (rec is None or rec(p))]
+        for subdir in dirs:
+            for p in subdir.visit(fil=fil, rec=rec, ignore=ignore):
+                yield p
+        for p in entries:
             if fil is None or fil(p):
                 yield p
-                if p.check(dir=1) and (rec is None or rec(p)):
-                    reclist.append(p)
 
     def _sortlist(self, res, sort):
         if sort:

py/path/local.py

@@ -334,12 +334,12 @@ class LocalPath(FSBase):
             assert self!=target
             copychunked(self, target)
         else:
-            target.ensure(dir=1)
             def rec(p):
                 return p.check(link=0)
             for x in self.visit(rec=rec):
                 relpath = x.relto(self)
                 newx = target.join(relpath)
+                newx.dirpath().ensure(dir=1)
                 if x.check(link=1):
                     newx.mksymlinkto(x.readlink())
                 elif x.check(file=1):

testing/path/test_local.py

@@ -198,6 +198,15 @@ class TestLocalPath(common.CommonFSTests):
         l2 = tmpdir.join(newfilename)
         assert l2.read() == 'foo'
 
+    def test_visit_depth_first(self, tmpdir):
+        p1 = tmpdir.ensure("a","1")
+        p2 = tmpdir.ensure("b","2")
+        p3 = tmpdir.ensure("breadth")
+        l = list(tmpdir.visit(lambda x: x.check(file=1)))
+        assert l[0] == p1
+        assert l[1] == p2 
+        assert l[2] == p3
+
 class TestExecutionOnWindows:
     disabled = py.std.sys.platform != 'win32'