Updated change logs. Changed error code to be clear that it was developer initiated.

5 files changed, 9 insertions, 4 deletions

diff --git a/platform/darwin/src/MGLMapSnapshotter.h b/platform/darwin/src/MGLMapSnapshotter.h
index a5ddcac0ac..82d1d65efd 100644
--- a/platform/darwin/src/MGLMapSnapshotter.h
+++ b/platform/darwin/src/MGLMapSnapshotter.h
@@ -197,6 +197,9 @@ MGL_EXPORT
  
  Once you call this method, you cannot resume the snapshot. In order to obtain
  the snapshot, create a new `MGLMapSnapshotter` object.
+
+ The completion handler will be called with an `NSError` with domain
+ `MGLErrorDomain` and error code `MGLErrorCodeSnapshotUserCancelled`.
  */
 - (void)cancel;
 
diff --git a/platform/darwin/src/MGLMapSnapshotter.mm b/platform/darwin/src/MGLMapSnapshotter.mm
index 3454275618..4a7d95c607 100644
--- a/platform/darwin/src/MGLMapSnapshotter.mm
+++ b/platform/darwin/src/MGLMapSnapshotter.mm
@@ -505,8 +505,8 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64;
 - (void)cancel
 {
     if (_snapshotCallback) {
-        [MGLMapSnapshotter completeWithErrorCode:MGLErrorCodeSnapshotCancelled
-                                     description:@"MGLMapSnapshotter cancelled."
+        [MGLMapSnapshotter completeWithErrorCode:MGLErrorCodeSnapshotUserCancelled
+                                     description:[NSString stringWithFormat:@"MGLMapSnapshotter cancelled from %s", __PRETTY_FUNCTION__]
                                          onQueue:self.resultQueue
                                       completion:self.completion];
         self.completion = nil;
diff --git a/platform/darwin/src/MGLTypes.h b/platform/darwin/src/MGLTypes.h
index c0590e4d7f..f2ea6e3a6c 100644
--- a/platform/darwin/src/MGLTypes.h
+++ b/platform/darwin/src/MGLTypes.h
@@ -51,7 +51,7 @@ typedef NS_ENUM(NSInteger, MGLErrorCode) {
     /** An error occurred while snapshotting the map. */
     MGLErrorCodeSnapshotFailed = 6,
     /** The user cancelled a map snapshot. */
-    MGLErrorCodeSnapshotCancelled = 7,
+    MGLErrorCodeSnapshotUserCancelled = 7,
 };
 
 /** Options for enabling debugging features in an `MGLMapView` instance. */
diff --git a/platform/ios/Integration Tests/Snapshotter Tests/MGLMapSnapshotterTest.m b/platform/ios/Integration Tests/Snapshotter Tests/MGLMapSnapshotterTest.m
index 67815ed96d..de8bc5c23a 100644
--- a/platform/ios/Integration Tests/Snapshotter Tests/MGLMapSnapshotterTest.m
+++ b/platform/ios/Integration Tests/Snapshotter Tests/MGLMapSnapshotterTest.m
@@ -170,7 +170,7 @@ MGLMapSnapshotter* snapshotterWithCoordinates(CLLocationCoordinate2D coordinates
 
         MGLTestAssertNil(strongself, snapshot);
         MGLTestAssert(strongself,
-                      ([error.domain isEqualToString:MGLErrorDomain] && error.code == MGLErrorCodeSnapshotCancelled),
+                      ([error.domain isEqualToString:MGLErrorDomain] && error.code == MGLErrorCodeSnapshotUserCancelled),
                       @"Should have been cancelled");
         [expectation fulfill];
     }];
diff --git a/platform/macos/CHANGELOG.md b/platform/macos/CHANGELOG.md
index d8a0067ad6..503685ac72 100644
--- a/platform/macos/CHANGELOG.md
+++ b/platform/macos/CHANGELOG.md
@@ -42,6 +42,8 @@
 * Fixed an issue where `-[MGLMapShapshot pointForCoordinate:]` returned incorrect points. ([#12221](https://github.com/mapbox/mapbox-gl-native/pull/12221))
 * Improved caching performance. ([#12072](https://github.com/mapbox/mapbox-gl-native/pull/12072))
 * Remove unnecessary memory use when collision debug mode is disabled. ([#12294](https://github.com/mapbox/mapbox-gl-native/issues/12294))
+* Changed `-[MGLMapSnapshotter cancel]` to call the completion block (originally passed to `-[MGLMapSnapshotter startWithQueue:completionHandler:]`) with an `NSError` (error code `MGLErrorCodeSnapshotUserCancelled`) if the snapshot has not finished. ([#12355](https://github.com/mapbox/mapbox-gl-native/pull/12355))
+
 
 ## 0.8.0 - June 20, 2018