Initial error handling code

include/core/SkRect.h

Index: include/core/SkRect.h
diff --git a/include/core/SkRect.h b/include/core/SkRect.h
index d8919ae5d6b888d3195cc57ce7346bc905cf2a8c..85baa6d5b5b7a3eb73ce40ab8b8e374d3f927d94 100644
--- a/include/core/SkRect.h
+++ b/include/core/SkRect.h
@@ -100,6 +100,8 @@ struct SK_API SkIRect {
      */
     bool isEmpty() const { return fLeft >= fRight || fTop >= fBottom; }
 
+    bool isValid() const { return (fLeft <= fRight) && (fTop <= fBottom); }

[reed1, 2013/09/03 20:25:21]

I think we already have the notion of "inverted" for rects. Seems like this
could use that name somehow.

isInverted() perhaps. That at least is more specific than "valid".

BTW - is it valid/safe if left < right, but right - left overflows a signed int?

[sugoi1, 2013/09/04 18:01:10]

Good point, I added a check to make sure width() and height() aren't oveflowing
the signed int.

+
     bool isLargest() const { return SK_MinS32 == fLeft &&
                                     SK_MinS32 == fTop &&
                                     SK_MaxS32 == fRight &&
@@ -419,6 +421,12 @@ struct SK_API SkRect {
      */
     bool isEmpty() const { return fLeft >= fRight || fTop >= fBottom; }
 
+    bool isValid() const { return SkScalarIsFinite(fLeft) &&
+                                  SkScalarIsFinite(fTop) &&
+                                  SkScalarIsFinite(fRight) &&
+                                  SkScalarIsFinite(fBottom) &&
+                                  (fLeft <= fRight) &&
+                                  (fTop <= fBottom); }
     /**
      *  Returns true iff all values in the rect are finite. If any are
      *  infinite or NaN (or SK_FixedNaN when SkScalar is fixed) then this