[ios, macos] Simplify MGLSource and subclasses (#7377)

* [ios, macos] Audited source headers for nullability

* [macos] Made MGLTileSet public

* [ios, macos] Replaced MGLTileSet with MGLTileSource

MGLRasterSource and MGLVectorSource now share a common abstract superclass, MGLTileSource. MGLTileSet has been removed. MGLTileSource is modeled after mbgl::style::RasterSource and mbgl::style::VectorSource. It has initializers that incorporate the parameters of MGLTileSet’s initializers, but it lacks getters for everything but the attribution string. MGLTileSet’s properties have been converted into options that can be passed into MGLTileSource’s initializers in a dictionary.

Properly implement rawSource as a covariant property so that it doesn’t end up getting autosynthesized as a shadow ivar. This prevents concrete subclasses of MGLSource from setting _rawSource directly but getting a different value out of self.rawSource.

Marked -[MGLSource init] as unavailable and ensured that concrete subclasses of MGLSource have the right set of initializers marked as designated initializers.

Documentation comments for each concrete source class identify the corresponding source type in the style specification. Clarified the purpose of MGLTileSetScheme, now known as MGLTileCoordinateSystem.

* [ios, macos] Clarified tile size interpretation

Sticking to a default value of 256 for mapbox: URLs, but other URLs get the standard 512 value.

* [ios, macos] rawSource is always set

* [ios, macos] Cleaned up MGLShapeSource initialization

rawSource is never nil, so there’s no need for a -commonInit method. Extracted -geoJSONOptions from MGLShapeSource into a standalone function for easier testing.

* [ios, macos] Synchronized headers in project

Realphabetized headers in groups. Added headers missing from one project or the other.

* [ios, macos] Added MGLShape methods to (de)serialize GeoJSON data

Added a class initializer and instance method to MGLShape that deserialize and serialize the shape as GeoJSON data, respectively. The new initializer handles parsing errors gracefully.

Removed methods specific to GeoJSON data from MGLShapeSource, in an effort to reduce parallel state. Developers are now expected to go through the new MGLShape initializer to get an MGLShape representation. Alternatively, a local file URL can be passed into the other MGLShapeSource initializer.

* [ios, macos] Typo in assertion message

* [ios, macos] Simplified GeoJSON serialization

Every MGLShape now knows its most specific mbgl::GeoJSON representation.

* [ios, macos] Reremoved MGLFeaturePrivate

mbgl::GeoJSON, which is a variant, allows a single GeoJSON representation method to traffic in whatever type is needed for a particular shape class. This change removes some hidden private protocols, which are a bug waiting to happen.

* [ios, macos] Fixed covariant rawLayer property

Properly implement rawLayer as a covariant property so that it doesn’t end up getting autosynthesized as a shadow ivar. This prevents concrete subclasses of MGLStyleLayer from setting _rawLayer directly but getting a different value out of self.rawLayer.

* [ios, macos] Use MGLAttributionInfo for source attribution

Made MGLAttributionInfo public. Replaced MGLTileSource’s attribution property with an attributionInfos property set to an array of MGLAttributionInfo objects. Added an MGLTileSourceOption for specifying an array of MGLAttributionInfo objects instead of an HTML string (either is acceptable when creating an MGLTileSource).

* [ios, macos] Corrected method references in documentation

1 files changed, 45 insertions, 0 deletions

diff --git a/platform/darwin/test/MGLGeometryTests.mm b/platform/darwin/test/MGLGeometryTests.mm
index b15916e6fa..0ffc27b29e 100644
--- a/platform/darwin/test/MGLGeometryTests.mm
+++ b/platform/darwin/test/MGLGeometryTests.mm
@@ -99,4 +99,49 @@
     XCTAssertFalse(MGLCoordinateInCoordinateBounds(kCLLocationCoordinate2DInvalid, wyoming));
 }
 
+- (void)testGeoJSONDeserialization {
+    NSData *data = [@"{\"type\": \"Feature\", \"geometry\": {\"type\": \"Point\", \"coordinates\": [0, 0]}, \"properties\": {}}" dataUsingEncoding:NSUTF8StringEncoding];
+    NSError *error;
+    MGLPointFeature *feature = (MGLPointFeature *)[MGLShape shapeWithData:data encoding:NSUTF8StringEncoding error:&error];
+    XCTAssertNil(error, @"Valid GeoJSON data should produce no error on deserialization.");
+    XCTAssertNotNil(feature, @"Valid GeoJSON data should produce an object on deserialization.");
+    XCTAssertTrue([feature isKindOfClass:[MGLPointFeature class]], @"Valid GeoJSON point feature data should produce an MGLPointFeature.");
+    XCTAssertEqual(feature.attributes.count, 0);
+    XCTAssertEqual(feature.coordinate.latitude, 0);
+    XCTAssertEqual(feature.coordinate.longitude, 0);
+    
+    data = [@"{\"type\": \"Feature\", \"feature\": {\"type\": \"Point\", \"coordinates\": [0, 0]}}" dataUsingEncoding:NSUTF8StringEncoding];
+    error = nil;
+    MGLShape *shape = [MGLShape shapeWithData:data encoding:NSUTF8StringEncoding error:&error];
+    XCTAssertNotNil(error, @"Invalid GeoJSON data should produce an error on deserialization.");
+    XCTAssertNil(shape, @"Invalid GeoJSON data should produce no object on deserialization.");
+}
+
+- (void)testGeoJSONSerialization {
+    MGLPointFeature *feature = [[MGLPointFeature alloc] init];
+    feature.identifier = @504;
+    feature.coordinate = CLLocationCoordinate2DMake(29.95, -90.066667);
+    
+    NSData *data = [feature geoJSONDataUsingEncoding:NSUTF8StringEncoding];
+    XCTAssertNotNil(data, @"MGLPointFeature should serialize as an UTF-8 string data object.");
+    NSError *error;
+    NSDictionary *serializedGeoJSON = [NSJSONSerialization JSONObjectWithData:data options:0 error:&error];
+    XCTAssertNil(error, @"Serialized GeoJSON data should be deserializable JSON.");
+    XCTAssertNotNil(serializedGeoJSON, @"Serialized GeoJSON data should be valid JSON.");
+    XCTAssertTrue([serializedGeoJSON isKindOfClass:[NSDictionary class]], @"Serialized GeoJSON data should be a JSON object.");
+    NSDictionary *geoJSON = @{
+        @"type": @"Feature",
+        @"id": @504,
+        @"geometry": @{
+            @"type": @"Point",
+            @"coordinates": @[
+                @(-90.066667),
+                @29.95,
+            ],
+        },
+        @"properties": @{},
+    };
+    XCTAssertEqualObjects(serializedGeoJSON, geoJSON, @"MGLPointFeature should serialize as a GeoJSON point feature.");
+}
+
 @end