fix nextContour bug

Calling nextContour() needs to ensure that we've already measured the "current" one.

Bug: skia:
Change-Id: I501c26d0b068028d67103888f06ec89125a5407a
Reviewed-on: https://skia-review.googlesource.com/114692
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Mike Reed <reed@google.com>

2 files changed, 13 insertions, 2 deletions

diff --git a/src/core/SkPathMeasure.cpp b/src/core/SkPathMeasure.cpp
index cdcd164018..4fb18934d9 100644
--- a/src/core/SkPathMeasure.cpp
+++ b/src/core/SkPathMeasure.cpp
@@ -667,7 +667,7 @@ bool SkPathMeasure::getSegment(SkScalar startD, SkScalar stopD, SkPath* dst,
 }
 
 bool SkPathMeasure::isClosed() {
-    (void)this->getLength();
+    (void)this->getLength();    // make sure we measure the current contour
     return fIsClosed;
 }
 
@@ -675,7 +675,8 @@ bool SkPathMeasure::isClosed() {
     we're done with the path.
 */
 bool SkPathMeasure::nextContour() {
-    fLength = -1;
+    (void)this->getLength();    // make sure we measure the current contour
+    fLength = -1;               // now signal that we should build the next set of segments
     return this->getLength() > 0;
 }
 
diff --git a/tests/PathMeasureTest.cpp b/tests/PathMeasureTest.cpp
index df66578f1b..bc75c5f122 100644
--- a/tests/PathMeasureTest.cpp
+++ b/tests/PathMeasureTest.cpp
@@ -217,3 +217,13 @@ DEF_TEST(PathMeasureConic, reporter) {
     REPORTER_ASSERT(reporter, 19.5f < stdP.fX && stdP.fX < 20.5f);
     REPORTER_ASSERT(reporter, 19.5f < hiP.fX && hiP.fX < 20.5f);
 }
+
+// Regression test for b/26425223
+DEF_TEST(PathMeasure_nextctr, reporter) {
+    SkPath path;
+    path.moveTo(0, 0); path.lineTo(100, 0);
+
+    SkPathMeasure meas(path, false);
+    // only expect 1 contour, even if we didn't explicitly call getLength() ourselves
+    REPORTER_ASSERT(reporter, !meas.nextContour());
+}