rewrite iterator to make msvc happy

Revert "Revert "add test for degenerate canvas dimension""

This reverts commit 1749af20a11d0f364dbb7cad8dc89101f956c923.

Bug: skia:
Change-Id: I382cbef397dfba600a6779b159764239399b177f
Reviewed-on: https://skia-review.googlesource.com/121344
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/tests/CanvasTest.cpp b/tests/CanvasTest.cpp
index 06e06f0934..95030a3e42 100644
--- a/tests/CanvasTest.cpp
+++ b/tests/CanvasTest.cpp
@@ -876,3 +876,25 @@ DEF_TEST(Canvas_SaveLayerWithNullBoundsAndZeroBoundsImageFilter, r) {
     REPORTER_ASSERT(r, canvas.getDeviceClipBounds().isEmpty());
     canvas.restore();
 }
+
+#include "SkPaintImageFilter.h"
+
+// Test that we don't crash/assert when building a canvas with degenerate coordintes
+// (esp. big ones, that might invoke tiling).
+DEF_TEST(Canvas_degenerate_dimension, reporter) {
+    // Need a paint that will sneak us past the quickReject in SkCanvas, so we can test the
+    // raster code further downstream.
+    SkPaint paint;
+    paint.setImageFilter(SkPaintImageFilter::Make(SkPaint(), nullptr));
+    REPORTER_ASSERT(reporter, !paint.canComputeFastBounds());
+
+    const int big = 100 * 1024; // big enough to definitely trigger tiling
+    const SkISize sizes[] {SkISize{0, big}, {big, 0}, {0, 0}};
+    for (SkISize size : sizes) {
+        SkBitmap bm;
+        bm.setInfo(SkImageInfo::MakeN32Premul(size.width(), size.height()));
+        SkCanvas canvas(bm);
+        canvas.drawRect({0, 0, 100, 90*1024}, paint);
+    }
+}
+