Merge pull request #3341 from bdbaddog/enhanced_debug_explain

Enhanced debug explain

1 files changed, 15 insertions, 4 deletions

diff --git a/src/engine/SCons/Node/__init__.py b/src/engine/SCons/Node/__init__.py
index 4280079..4c35f4c 100644
--- a/src/engine/SCons/Node/__init__.py
+++ b/src/engine/SCons/Node/__init__.py
@@ -50,6 +50,11 @@ import collections
 import copy
 from itertools import chain
 
+try:
+    from itertools import zip_longest
+except ImportError:
+    from itertools import izip_longest as zip_longest
+
 import SCons.Debug
 from SCons.Debug import logInstanceCreation
 import SCons.Executor
@@ -1686,9 +1691,16 @@ class Node(object, with_metaclass(NoSlotsPyPy)):
                     lines.append("`%s' changed\n" % stringify(k))
 
         if len(lines) == 0 and old_bkids != new_bkids:
-            lines.append("the dependency order changed:\n" +
-                         "%sold: %s\n" % (' '*15, list(map(stringify, old_bkids))) +
-                         "%snew: %s\n" % (' '*15, list(map(stringify, new_bkids))))
+            lines.append("the dependency order changed:\n")
+            lines.append("->Sources\n")
+            for (o,n) in zip_longest(old.bsources, new.bsources, fillvalue=None):
+                lines.append("Old:%s\tNew:%s\n"%(o,n))
+            lines.append("->Depends\n")
+            for (o,n) in zip_longest(old.bdepends, new.bdepends, fillvalue=None):
+                lines.append("Old:%s\tNew:%s\n"%(o,n))
+            lines.append("->Implicit\n")
+            for (o,n) in zip_longest(old.bimplicit, new.bimplicit, fillvalue=None):
+                lines.append("Old:%s\tNew:%s\n"%(o,n))
 
         if len(lines) == 0:
             def fmt_with_title(title, strlines):
@@ -1731,7 +1743,6 @@ class Walker(object):
     This is depth-first, children are visited before the parent.
     The Walker object can be initialized with any node, and
     returns the next node on the descent with each get_next() call.
-    'kids_func' is an optional function that will be called to
     get the children of a node instead of calling 'children'.
     'cycle_func' is an optional function that will be called
     when a cycle is detected.