[gimp] Bug 632568 - 'gimp-drawable-transform-rotate-simple' makes GIMP crash in some cases

[Michael Natterer <mitch src gnome org>]

commit 1c8149a553c5cc4532cffe9c7266298de502c3bf
Author: Michael Natterer <mitch gimp org>
Date:   Fri Mar 18 00:51:05 2011 +0100

    Bug 632568 - 'gimp-drawable-transform-rotate-simple' makes GIMP crash in some cases
    
    Applied modified patch from Massimo that makes sure we don't use
    negative width/height if source and dest regions don't overlap.

 app/core/gimpdrawable-transform.c |   13 +++++++---
 app/tests/test-core.c             |   49 +++++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+), 4 deletions(-)
---
diff --git a/app/core/gimpdrawable-transform.c b/app/core/gimpdrawable-transform.c
index d0a9914..5e4af20 100644
--- a/app/core/gimpdrawable-transform.c
+++ b/app/core/gimpdrawable-transform.c
@@ -455,10 +455,15 @@ gimp_drawable_transform_tiles_rotate (GimpDrawable     *drawable,
               orig_height  = clip_width;
               break;
             }
-        }
 
-      new_width  = clip_width;
-      new_height = clip_height;
+          new_width  = clip_width;
+          new_height = clip_height;
+        }
+      else
+        {
+          new_width  = 0;
+          new_height = 0;
+        }
     }
   else
     {
@@ -472,7 +477,7 @@ gimp_drawable_transform_tiles_rotate (GimpDrawable     *drawable,
       new_y  = 0;
     }
 
-  if (new_width == 0 && new_height == 0)
+  if (new_width < 1 || new_height < 1)
     return new_tiles;
 
   pixel_region_init (&srcPR, orig_tiles,
diff --git a/app/tests/test-core.c b/app/tests/test-core.c
index bd98df6..ea8c9ba 100644
--- a/app/tests/test-core.c
+++ b/app/tests/test-core.c
@@ -23,6 +23,7 @@
 #include "widgets/gimpuimanager.h"
 
 #include "core/gimp.h"
+#include "core/gimpcontext.h"
 #include "core/gimpimage.h"
 #include "core/gimplayer.h"
 
@@ -97,6 +98,49 @@ gimp_test_image_teardown (GimpTestFixture *fixture,
 }
 
 /**
+ * rotate_non_overlapping:
+ * @fixture:
+ * @data:
+ *
+ * Super basic test that makes sure we can add a layer
+ * and call gimp_item_rotate with center at (0, -10)
+ * without triggering a failed assertion .
+ **/
+static void
+rotate_non_overlapping (GimpTestFixture *fixture,
+                        gconstpointer    data)
+{
+  GimpImage   *image = fixture->image;
+  GimpLayer   *layer;
+  GimpContext *context = gimp_context_new (gimp, "Test", NULL /*template*/);
+  gboolean     result;
+
+  g_assert_cmpint (gimp_image_get_n_layers (image), ==, 0);
+
+  layer = gimp_layer_new (image,
+                          GIMP_TEST_IMAGE_SIZE,
+                          GIMP_TEST_IMAGE_SIZE,
+                          GIMP_RGBA_IMAGE,
+                          "Test Layer",
+                          1.0,
+                          GIMP_NORMAL_MODE);
+
+  g_assert_cmpint (GIMP_IS_LAYER (layer), ==, TRUE);
+
+  result = gimp_image_add_layer (image,
+                                 layer,
+                                 GIMP_IMAGE_ACTIVE_PARENT,
+                                 0,
+                                 FALSE);
+
+  gimp_item_rotate (GIMP_ITEM (layer), context, GIMP_ROTATE_90, 0., -10., TRUE);
+
+  g_assert_cmpint (result, ==, TRUE);
+  g_assert_cmpint (gimp_image_get_n_layers (image), ==, 1);
+  g_object_unref (context);
+}
+
+/**
  * add_layer:
  * @fixture:
  * @data:
@@ -196,10 +240,15 @@ main (int    argc,
   /* Add tests */
   ADD_IMAGE_TEST (add_layer);
   ADD_IMAGE_TEST (remove_layer);
+  ADD_IMAGE_TEST (rotate_non_overlapping);
 
   /* Run the tests */
   result = g_test_run ();
 
+  /* Don't write files to the source dir */
+  gimp_test_utils_set_gimp2_directory ("GIMP_TESTING_ABS_TOP_BUILDDIR",
+                                       "app/tests/gimpdir-output");
+
   /* Exit so we don't break script-fu plug-in wire */
   gimp_exit (gimp, TRUE);