[PATCH] siggen: Ensure correct runtask dependency output is shown for diffsigs

[Richard Purdie <richard.purdie@linuxfoundation.org>]

The actual task names are discounted for comparison of dependent tasks, only
the actual hashes are used. This updates the comparison code to account for
this change, attempting heuristic matching for more user friendly output but
falling back to showing the changed hashes directly. This avoids some confusing
output to users where it looked like tasks had changed when they had not and
actually had the same hash but a different taskname.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
---
diff --git a/bitbake/lib/bb/siggen.py b/bitbake/lib/bb/siggen.py
index 22417b9..d9d0294 100644
--- a/bitbake/lib/bb/siggen.py
+++ b/bitbake/lib/bb/siggen.py
@@ -281,21 +281,27 @@ def compare_sigfiles(a, b):
             print "Variable %s value changed from %s to %s" % (dep, a_data['varvals'][dep], b_data['varvals'][dep])
 
     if 'runtaskhashes' in a_data and 'runtaskhashes' in b_data:
-        a = clean_basepaths(a_data['runtaskhashes'])
-        b = clean_basepaths(b_data['runtaskhashes'])
-        changed, added, removed = dict_diff(a, b)
-        if added:
-            for dep in added:
-                print "Dependency on task %s was added" % (dep)
-        if removed:
-            for dep in removed:
-                print "Dependency on task %s was removed" % (dep)
-        if changed:
-            for dep in changed:
-                print "Hash for dependent task %s changed from %s to %s" % (dep, a[dep], b[dep])
-    elif 'runtaskdeps' in a_data and 'runtaskdeps' in b_data and sorted(a_data['runtaskdeps']) != sorted(b_data['runtaskdeps']):
-        print "Tasks this task depends on changed from %s to %s" % (sorted(a_data['runtaskdeps']), sorted(b_data['runtaskdeps']))
-        print "changed items: %s" % a_data['runtaskdeps'].symmetric_difference(b_data['runtaskdeps'])
+        if len(a_data['runtaskdeps']) != len(b_data['runtaskdeps']):
+            a = clean_basepaths(a_data['runtaskhashes'])
+            b = clean_basepaths(b_data['runtaskhashes'])
+            changed, added, removed = dict_diff(a, b)
+            if added:
+                for dep in added:
+                    print "Dependency on task %s was added" % (dep)
+            if removed:
+                for dep in removed:
+                    print "Dependency on task %s was removed" % (dep)
+            if changed:
+                for dep in changed:
+                    print "Hash for dependent task %s changed from %s to %s" % (dep, a[dep], b[dep])
+        else:
+            for i in range(len(a_data['runtaskdeps'])):
+                aent = a_data['runtaskdeps'][i]
+                bent = b_data['runtaskdeps'][i]
+                aname = clean_basepath(aent)
+                bname = clean_basepath(bent)
+                if a_data['runtaskhashes'][aent] != b_data['runtaskhashes'][bent]:
+                    print "Task dependency hash changed from %s to %s (for %s and %s)" % (a_data['runtaskhashes'][aent], b_data['runtaskhashes'][bent], aname, bname)
 
 def dump_sigfile(a):
     p1 = pickle.Unpickler(file(a, "rb"))