Prevent stopless functions (#7309)

* [ios, macos] prevent stopless functions

* [ios, macos] removed unused bridging header and fixed naming

5 files changed, 26 insertions, 2 deletions

diff --git a/platform/darwin/src/MGLStyleValue.mm b/platform/darwin/src/MGLStyleValue.mm
index 43b51d6788..6ced819cd1 100644
--- a/platform/darwin/src/MGLStyleValue.mm
+++ b/platform/darwin/src/MGLStyleValue.mm
@@ -63,6 +63,10 @@
 
 - (instancetype)initWithBase:(CGFloat)base stops:(NSDictionary *)stops {
     if (self = [super init]) {
+        if (!stops.count)
+        {
+            [NSException raise:NSInvalidArgumentException format:@"%@ requires at least one stop.", self];
+        }
         _base = base;
         _stops = stops;
     }
diff --git a/platform/darwin/test/MGLStyleValueTests.h b/platform/darwin/test/MGLStyleValueTests.h
new file mode 100644
index 0000000000..a563de39f0
--- /dev/null
+++ b/platform/darwin/test/MGLStyleValueTests.h
@@ -0,0 +1,4 @@
+#import <XCTest/XCTest.h>
+
+@interface MGLStyleValueTests : XCTestCase
+@end
diff --git a/platform/darwin/test/MGLStyleValueTests.m b/platform/darwin/test/MGLStyleValueTests.m
new file mode 100644
index 0000000000..fe6096584d
--- /dev/null
+++ b/platform/darwin/test/MGLStyleValueTests.m
@@ -0,0 +1,13 @@
+#import <XCTest/XCTest.h>
+#import <Mapbox/Mapbox.h>
+
+@interface MGLStyleValueTests : XCTestCase
+@end
+
+@implementation MGLStyleValueTests
+
+- (void)testStoplessFunction {
+    XCTAssertThrowsSpecificNamed([MGLStyleValue<NSNumber *> valueWithStops:@{}], NSException, NSInvalidArgumentException, @"Stopless function should raise an exception");
+}
+
+@end
diff --git a/platform/darwin/test/MGLStyleValueTests.swift b/platform/darwin/test/MGLStyleValueTests.swift
index aa9b003236..7a266a495f 100644
--- a/platform/darwin/test/MGLStyleValueTests.swift
+++ b/platform/darwin/test/MGLStyleValueTests.swift
@@ -1,7 +1,9 @@
 import XCTest
 import Mapbox
 
-class MGLStyleValueTests: XCTestCase {
+
+extension MGLStyleValueTests {
+    
     func testConstantValues() {
         let geoJSONSource = MGLGeoJSONSource(identifier: "test", shape: nil, options: nil)
         let symbolStyleLayer = MGLSymbolStyleLayer(identifier: "test", source: geoJSONSource)
@@ -29,7 +31,7 @@ class MGLStyleValueTests: XCTestCase {
             2: MGLStyleValue(rawValue: false),
             3: MGLStyleValue(rawValue: true),
             4: MGLStyleValue(rawValue: false),
-        ]
+            ]
         symbolStyleLayer.iconAllowOverlap = MGLStyleFunction<NSNumber>(base: 1, stops: stops)
         XCTAssertEqual((symbolStyleLayer.iconAllowOverlap as! MGLStyleFunction<NSNumber>), MGLStyleFunction(base: 1, stops: stops))
     }
diff --git a/platform/darwin/test/test-Bridging-Header.h b/platform/darwin/test/test-Bridging-Header.h
index e11d920b12..5d23e9d6c5 100644
--- a/platform/darwin/test/test-Bridging-Header.h
+++ b/platform/darwin/test/test-Bridging-Header.h
@@ -1,3 +1,4 @@
 //
 //  Use this file to import your target's public headers that you would like to expose to Swift.
 //
+#import "MGLStyleValueTests.h"