[ios, macos] Insert example code in original headers (#7569)

* [ios, macos] Removed extraneous code fences

* [ios] Streamlined example delimiters

Use test method names as names of example blocks and test method documentation comments as front matter for examples. Set off example blocks using a syntax similar to playground markup syntax. Avoid hard-coding indentation levels. Trigger Xcode build error when an error occurs in the script.

* [ios] Removed platform-specific code from examples

* [ios] Fixed logic error

The comment said 200 while the code said 1,500.

* [ios] Formalize build phase input

* [ios] Insert examples into original source documentation

Rewrote the example code insertion script to work on the original source files and overwrite any existing code examples on the same symbols. The script uses SourceKitten to find the documentation comment for the symbol named by the test method.

Replaced the Run Script build phase that runs the example code insertion script with a make rule that runs the same script. Inlined skeleton examples minus the contents of the code blocks.

* [ios] Fixed syntax error

* [ios] Ran ios-add-examples-to-docs

* [ios] Avoid touching unchanged headers

* [ios] Refactored example insertion script

* [ios] Point jazzy at original sources

* [ios] Invoke SourceKitten only once

* [ios] Look for methods as well as properties

* [ios] Thoroughly search for code blocks in doc comments

Refactored the example code insertion script to index test methods by their names, then recursively search the SourceKitten output for documentation comments that contain Swift code blocks, replacing each code block with the associated test method body.

* [ios, macos] Enabled example insertion for macOS

The example code insertion script is now platform-agnostic.

* [ios, macos] Fixed documentation example tests

Set the map view’s style to a minimal local JSON file. Wait for the style to finish loading before running each test. Corrected CGVector type.

* [ios, macos] Dry run mode

The output of this mode isn’t a good indicator of whether any files would’ve needed to be changed, because the presence of a conditional compilation block in one of the test methods means this script would always change and revert the corresponding comment.

* [ios] Fixed test failure

The iOS implementation of MGLMapView tries to show the Streets style by default even if no access token has been set. Avoid a race condition and frequent test failure by specifying the minimal style on initialization.

* [ios, macos] Ensure SourceKitten is installed before inserting example code

* [ios, macos] Tear down map view after each test

Keep map views from previous tests from hanging around, potentially obscuring the result of a subsequent test. Set the access token to a bogus token upfront for all style layer tests. Unified MGLStyle usage within MGLStyleTests.

* [ios, macos] Reinsert examples after generating runtime styling headers

15 files changed, 521 insertions, 42 deletions

diff --git a/platform/darwin/scripts/update-examples.js b/platform/darwin/scripts/update-examples.js
new file mode 100644
index 0000000000..2aeb80e139
--- /dev/null
+++ b/platform/darwin/scripts/update-examples.js
@@ -0,0 +1,152 @@
+'use strict';
+
+const fs = require('fs');
+const execFileSync = require('child_process').execFileSync;
+const _ = require('lodash');
+
+const examplesSrc = fs.readFileSync('platform/darwin/test/MGLDocumentationExampleTests.swift', 'utf8');
+
+// Regex extracts the following block
+// /** Front matter to describe the example. **/
+// func testMGLClass$member() {
+//     ...
+//     //#-example-code
+//     let sampleCode: String?
+//     //#-end-example-code
+//     ...
+// }
+//
+// into the following regex groups:
+// 1 (test method name): "MGLClass" or "MGLClass$member" or "MGLClass$initWithArg_anotherArg_"
+// 2 (indentation): "    "
+// 3 (sample code): "let sampleCode: String?"
+const exampleRegex = /func test([\w$]+)\s*\(\)\s*\{[^]*?\n([ \t]+)\/\/#-example-code\n([^]+?)\n\2\/\/#-end-example-code\n/gm;
+
+/**
+ * Returns the given source with example code inserted into the documentation
+ * comment for the symbol at the given one-based line.
+ *
+ * @param {String} src Source code to insert the example code into.
+ * @param {Number} line One-based line number of the symbol being documented.
+ * @param {String} exampleCode Example code to insert.
+ * @returns {String} `src` with `exampleCode` inserted just above `line`.
+ */
+function completeSymbolInSource(src, line, exampleCode) {
+  // Split the file contents right before the symbol declaration (but after its documentation comment).
+  let srcUpToSymbol = src.split('\n', line - 1).join('\n');
+  let srcFromSymbol = src.substr(srcUpToSymbol.length);
+  
+  // Match the documentation comment block that is not followed by the beginning or end of a declaration.
+  let commentMatch = srcUpToSymbol.match(/\/\*\*\s*(?:[^*]|\*(?!\/))+?\s*\*\/[^;{}]*?$/);
+  
+  // Replace the Swift code block with the test method’s contents.
+  let completedComment = commentMatch[0].replace(/^([ \t]*)```swift\n[^]*?```/m, function (m, indentation) {
+    // Apply the original indentation to each line.
+    return ('```swift\n' + exampleCode + '\n```').replace(/^/gm, indentation);
+  });
+  
+  // Splice the modified comment into the overall file contents.
+  srcUpToSymbol = (srcUpToSymbol.substr(0, commentMatch.index) + completedComment +
+                   srcUpToSymbol.substr(commentMatch.index + commentMatch[0].length));
+  return srcUpToSymbol + srcFromSymbol;
+}
+
+let examples = {};
+let match;
+while ((match = exampleRegex.exec(examplesSrc)) !== null) {
+  let testMethodName = match[1],
+      indentation = match[2],
+      exampleCode = match[3];
+
+  // Trim leading whitespace from the example code.
+  exampleCode = exampleCode.replace(new RegExp('^' + indentation, 'gm'), '');
+  
+  examples[testMethodName] = exampleCode;
+}
+
+function completeExamples(os) {
+  console.log(`Installing ${os} SDK examples…`);
+  
+  let sdk = os === 'iOS' ? 'iphonesimulator' : 'macosx';
+  let sysroot = execFileSync('xcrun', ['--show-sdk-path', '--sdk', sdk]).toString().trim();
+  let umbrellaPath = `platform/${os.toLowerCase()}/src/Mapbox.h`;
+  let docArgs = ['doc', '--objc', umbrellaPath, '--',
+                 '-x', 'objective-c', '-I', 'platform/darwin/src/', '-isysroot', sysroot];
+  let docStr = execFileSync('sourcekitten', docArgs).toString().trim();
+  let docJson = JSON.parse(docStr);
+  _.forEach(docJson, function (result) {
+    _.forEach(result, function (structure, path) {
+      let src;
+      let newSrc;
+      // Recursively search for code blocks in documentation comments and populate
+      // them with example code from the test methods. Find and replace the code
+      // blocks in reverse to keep the SourceKitten line numbers accurate.
+      _.forEachRight(structure['key.substructure'], function completeSubstructure(substructure, idx, substructures, symbolPath) {
+        if (!symbolPath) {
+          symbolPath = [substructure['key.name']];
+        }
+        _.forEachRight(substructure['key.substructure'], function (substructure, idx, substructures) {
+          completeSubstructure(substructure, idx, substructures, _.concat(symbolPath, substructure['key.name']));
+        });
+        
+        let comment = substructure['key.doc.comment'];
+        if (!comment || !comment.match(/^(?:\s*)```swift\n/m)) {
+          return;
+        }
+        
+        // Lazily read in the existing file.
+        if (!src) {
+          newSrc = src = fs.readFileSync(path, 'utf8');
+        }
+        
+        // Get the contents of the test method whose name matches the symbol path.
+        let testMethodName = symbolPath.join('$').replace(/$[+-]/, '').replace(/:/g, '_');
+        let example = examples[testMethodName];
+        if (!example) {
+          console.error(`MGLDocumentationExampleTests.${testMethodName}() not found.`);
+          process.exit(1);
+        }
+        
+        // Resolve conditional compilation blocks.
+        example = example.replace(/^(\s*)#if\s+os\((iOS|macOS)\)\n([^]*?)(?:^\1#else\n([^]*?))?^\1#endif\n/gm,
+                                  function (m, indentation, ifOs, ifCase, elseCase) {
+          return (os === ifOs ? ifCase : elseCase).replace(new RegExp('^    ', 'gm'), '');
+        });
+        
+        // Insert the test method contents into the documentation comment just
+        // above the substructure.
+        let startLine = substructure['key.parsed_scope.start'];
+        newSrc = completeSymbolInSource(newSrc, startLine, example);
+      });
+      
+      if (!src) {
+        return;
+      }
+      
+      // Write out the modified file contents.
+      if (src === newSrc) {
+        console.log('Skipping', path);
+      } else {
+        console.log('Updating', path);
+        if (['0', 'false'].indexOf(process.env.DRY_RUN || '0') !== -1) {
+          fs.writeFileSync(path, newSrc);
+        }
+      }
+    });
+  });
+}
+
+function ensureSourceKittenIsInstalled() {
+  try {
+    execFileSync('which', ['sourcekitten']);
+  } catch (e) {
+    console.log(`Installing SourceKitten via Homebrew…`);
+    execFileSync('brew', ['install', 'sourcekitten']);
+  }
+}
+
+ensureSourceKittenIsInstalled();
+
+// Where a particular comment is part of both SDKs, prefer the iOS example.
+completeExamples('macOS');
+completeExamples('iOS');
diff --git a/platform/darwin/src/MGLCircleStyleLayer.h b/platform/darwin/src/MGLCircleStyleLayer.h
index b57e245da2..d2e043e22a 100644
--- a/platform/darwin/src/MGLCircleStyleLayer.h
+++ b/platform/darwin/src/MGLCircleStyleLayer.h
@@ -59,8 +59,21 @@ typedef NS_ENUM(NSUInteger, MGLCircleTranslateAnchor) {
  otherwise, find it using the `MGLStyle.layers` property. You can also create a
  new circle style layer and add it to the style using a method such as
  `-[MGLStyle addLayer:]`.
-
- <!--EXAMPLE: MGLCircleStyleLayer-->
+ 
+ ### Example
+ 
+ ```swift
+ let layer = MGLCircleStyleLayer(identifier: "circles", source: population)
+ layer.sourceLayerIdentifier = "population"
+ layer.circleColor = MGLStyleValue(rawValue: .green)
+ layer.circleRadius = MGLStyleValue(interpolationBase: 1.75, stops: [
+     12: MGLStyleValue(rawValue: 2),
+     22: MGLStyleValue(rawValue: 180)
+ ])
+ layer.circleOpacity = MGLStyleValue(rawValue: 0.7)
+ layer.predicate = NSPredicate(format: "%K == %@", "marital-status", "married")
+ mapView.style.addLayer(layer)
+ ```
  */
 @interface MGLCircleStyleLayer : MGLVectorStyleLayer
 
diff --git a/platform/darwin/src/MGLFillStyleLayer.h b/platform/darwin/src/MGLFillStyleLayer.h
index 2638e85aa5..184f44ef65 100644
--- a/platform/darwin/src/MGLFillStyleLayer.h
+++ b/platform/darwin/src/MGLFillStyleLayer.h
@@ -37,8 +37,16 @@ typedef NS_ENUM(NSUInteger, MGLFillTranslateAnchor) {
  otherwise, find it using the `MGLStyle.layers` property. You can also create a
  new fill style layer and add it to the style using a method such as
  `-[MGLStyle addLayer:]`.
-
- <!--EXAMPLE: MGLFillStyleLayer-->
+ 
+ ### Example
+ 
+ ```swift
+ let layer = MGLFillStyleLayer(identifier: "parks", source: parks)
+ layer.sourceLayerIdentifier = "parks"
+ layer.fillColor = MGLStyleValue(rawValue: .green)
+ layer.predicate = NSPredicate(format: "type == %@", "national-park")
+ mapView.style.addLayer(layer)
+ ```
  */
 @interface MGLFillStyleLayer : MGLVectorStyleLayer
 
diff --git a/platform/darwin/src/MGLLineStyleLayer.h b/platform/darwin/src/MGLLineStyleLayer.h
index c3371aa2a7..f049ae1db1 100644
--- a/platform/darwin/src/MGLLineStyleLayer.h
+++ b/platform/darwin/src/MGLLineStyleLayer.h
@@ -87,8 +87,21 @@ typedef NS_ENUM(NSUInteger, MGLLineTranslateAnchor) {
  otherwise, find it using the `MGLStyle.layers` property. You can also create a
  new line style layer and add it to the style using a method such as
  `-[MGLStyle addLayer:]`.
-
- <!--EXAMPLE: MGLLineStyleLayer-->
+ 
+ ### Example
+ 
+ ```swift
+ let layer = MGLLineStyleLayer(identifier: "trails-path", source: trails)
+ layer.sourceLayerIdentifier = "trails"
+ layer.lineWidth = MGLStyleValue(interpolationBase: 1.5, stops: [
+     14: MGLStyleValue(rawValue: 2),
+     18: MGLStyleValue(rawValue: 20),
+ ])
+ layer.lineColor = MGLStyleValue(rawValue: .brown)
+ layer.lineCap = MGLStyleValue(rawValue: NSValue(mglLineCap: .round))
+ layer.predicate = NSPredicate(format: "%K == %@", "trail-type", "mountain-biking")
+ mapView.style.addLayer(layer)
+ ```
  */
 @interface MGLLineStyleLayer : MGLVectorStyleLayer
 
diff --git a/platform/darwin/src/MGLRasterSource.h b/platform/darwin/src/MGLRasterSource.h
index 3efd84f383..cd95e85c5b 100644
--- a/platform/darwin/src/MGLRasterSource.h
+++ b/platform/darwin/src/MGLRasterSource.h
@@ -35,8 +35,19 @@ extern const MGLTileSourceOption MGLTileSourceOptionTileSize;
  `MGLRasterSource` object that you can use to initialize new style layers. You
  can also add and remove sources dynamically using methods such as
  `-[MGLStyle addSource:]` and `-[MGLStyle sourceWithIdentifier:]`.
-
- <!--EXAMPLE: MGLRasterSource-->
+ 
+ ### Example
+ 
+ ```swift
+ let source = MGLRasterSource(identifier: "clouds", tileURLTemplates: ["https://example.com/raster-tiles/{z}/{x}/{y}.png"], options: [
+     .minimumZoomLevel: 9,
+     .maximumZoomLevel: 16,
+     .tileSize: 512,
+     .attributionInfos: [
+         MGLAttributionInfo(title: NSAttributedString(string: "© Mapbox"), url: URL(string: "http://mapbox.com"))
+     ]
+ ])
+ mapView.style.addSource(source)
  ```
  */
 @interface MGLRasterSource : MGLTileSource
diff --git a/platform/darwin/src/MGLRasterStyleLayer.h b/platform/darwin/src/MGLRasterStyleLayer.h
index 7b53eebf96..45ab25a8f1 100644
--- a/platform/darwin/src/MGLRasterStyleLayer.h
+++ b/platform/darwin/src/MGLRasterStyleLayer.h
@@ -23,8 +23,14 @@ NS_ASSUME_NONNULL_BEGIN
  otherwise, find it using the `MGLStyle.layers` property. You can also create a
  new raster style layer and add it to the style using a method such as
  `-[MGLStyle addLayer:]`.
-
- <!--EXAMPLE: MGLRasterStyleLayer-->
+ 
+ ### Example
+ 
+ ```swift
+ let layer = MGLRasterStyleLayer(identifier: "clouds", source: source)
+ layer.rasterOpacity = MGLStyleValue(rawValue: 0.5)
+ mapView.style.addLayer(layer)
+ ```
  */
 @interface MGLRasterStyleLayer : MGLForegroundStyleLayer
 
diff --git a/platform/darwin/src/MGLShapeSource.h b/platform/darwin/src/MGLShapeSource.h
index 0eb454437b..30e299d2b1 100644
--- a/platform/darwin/src/MGLShapeSource.h
+++ b/platform/darwin/src/MGLShapeSource.h
@@ -74,8 +74,18 @@ extern const MGLShapeSourceOption MGLShapeSourceOptionSimplificationTolerance;
  
  Any vector style layer initialized with a shape source should have a `nil`
  value in its `sourceLayerIdentifier` property.
-
- <!--EXAMPLE: MGLShapeSource-->
+ 
+ ### Example
+ 
+ ```swift
+ var coordinates: [CLLocationCoordinate2D] = [
+     CLLocationCoordinate2D(latitude: 37.77, longitude: -122.42),
+     CLLocationCoordinate2D(latitude: 38.91, longitude: -77.04),
+ ]
+ let polyline = MGLPolylineFeature(coordinates: &coordinates, count: UInt(coordinates.count))
+ let shape = MGLShapeCollectionFeature(shapes: [polyline])
+ let source = MGLShapeSource(identifier: "lines", shape: shape, options: nil)
+ mapView.style.addSource(source)
  ```
  */
 @interface MGLShapeSource : MGLSource
diff --git a/platform/darwin/src/MGLStyleLayer.h.ejs b/platform/darwin/src/MGLStyleLayer.h.ejs
index ac95022ea7..17529b8f9d 100644
--- a/platform/darwin/src/MGLStyleLayer.h.ejs
+++ b/platform/darwin/src/MGLStyleLayer.h.ejs
@@ -67,8 +67,11 @@ typedef NS_ENUM(NSUInteger, MGL<%- camelize(property.name) %>) {
  otherwise, find it using the `MGLStyle.layers` property. You can also create a
  new <%- type %> style layer and add it to the style using a method such as
  `-[MGLStyle addLayer:]`.
-
- <!--EXAMPLE: MGL<%- camelize(type) %>StyleLayer-->
+ 
+ ### Example
+ 
+ ```swift
+ ```
  */
 <% } -%>
 @interface MGL<%- camelize(type) %>StyleLayer : MGL<%-
diff --git a/platform/darwin/src/MGLSymbolStyleLayer.h b/platform/darwin/src/MGLSymbolStyleLayer.h
index 052d67617a..ca34698159 100644
--- a/platform/darwin/src/MGLSymbolStyleLayer.h
+++ b/platform/darwin/src/MGLSymbolStyleLayer.h
@@ -260,8 +260,21 @@ typedef NS_ENUM(NSUInteger, MGLTextTranslateAnchor) {
  otherwise, find it using the `MGLStyle.layers` property. You can also create a
  new symbol style layer and add it to the style using a method such as
  `-[MGLStyle addLayer:]`.
-
- <!--EXAMPLE: MGLSymbolStyleLayer-->
+ 
+ ### Example
+ 
+ ```swift
+ let layer = MGLSymbolStyleLayer(identifier: "coffeeshops", source: pois)
+ layer.sourceLayerIdentifier = "pois"
+ layer.iconImageName = MGLStyleValue(rawValue: "coffee")
+ layer.iconScale = MGLStyleValue(rawValue: 0.5)
+ layer.textField = MGLStyleValue(rawValue: "{name}")
+ layer.textTranslate = MGLStyleValue(rawValue: NSValue(cgVector: CGVector(dx: 10, dy: 0)))
+ layer.textJustification = MGLStyleValue(rawValue: NSValue(mglTextJustification: .left))
+ layer.textAnchor = MGLStyleValue(rawValue: NSValue(mglTextAnchor: .left))
+ layer.predicate = NSPredicate(format: "%K == %@", "venue-type", "coffee")
+ mapView.style.addLayer(layer)
+ ```
  */
 @interface MGLSymbolStyleLayer : MGLVectorStyleLayer
 
diff --git a/platform/darwin/src/MGLVectorSource.h b/platform/darwin/src/MGLVectorSource.h
index ba8f075b5a..aa867adb6c 100644
--- a/platform/darwin/src/MGLVectorSource.h
+++ b/platform/darwin/src/MGLVectorSource.h
@@ -24,8 +24,19 @@ NS_ASSUME_NONNULL_BEGIN
  (<var>extent</var>&nbsp;×&nbsp;2)&nbsp;−&nbsp;1, inclusive. Any vector style
  layer initialized with a vector source must have a non-`nil` value in its
  `sourceLayerIdentifier` property.
-
- <!--EXAMPLE: MGLVectorSource-->
+ 
+ ### Example
+ 
+ ```swift
+ let source = MGLVectorSource(identifier: "pois", tileURLTemplates: ["https://example.com/vector-tiles/{z}/{x}/{y}.mvt"], options: [
+     .minimumZoomLevel: 9,
+     .maximumZoomLevel: 16,
+     .attributionInfos: [
+         MGLAttributionInfo(title: NSAttributedString(string: "© Mapbox"), url: URL(string: "http://mapbox.com"))
+     ]
+ ])
+ mapView.style.addSource(source)
+ ```
  */
 @interface MGLVectorSource : MGLTileSource
 
diff --git a/platform/darwin/src/MGLVectorStyleLayer.h b/platform/darwin/src/MGLVectorStyleLayer.h
index 50e56d8643..d33494c3e4 100644
--- a/platform/darwin/src/MGLVectorStyleLayer.h
+++ b/platform/darwin/src/MGLVectorStyleLayer.h
@@ -59,7 +59,10 @@ NS_ASSUME_NONNULL_BEGIN
  <li><code>NSContainsPredicateOperatorType</code> (<code>CONTAINS</code>)</li>
  </ul>
  
- To test whether a feature has or lacks a specific attribute, compare the attribute to `NULL` or `NIL`. Predicates created using the `+[NSPredicate predicateWithValue:]` method are also supported. String operators and custom operators are not supported.
+ To test whether a feature has or lacks a specific attribute, compare the
+ attribute to `NULL` or `NIL`. Predicates created using the
+ `+[NSPredicate predicateWithValue:]` method are also supported. String
+ operators and custom operators are not supported.
  
  For details about the predicate format string syntax, consult the “Predicate
  Format String Syntax” chapter of the
@@ -130,8 +133,19 @@ NS_ASSUME_NONNULL_BEGIN
  style attributes and also `hyphen-minus` and `tag:subtag`. However, you must use
  `%K` in the format string to represent these variables:
  `@"%K == 'LineString'", @"$type"`.
-
- <!--EXAMPLE: MGLVectorStyleLayer.predicate-->
+ 
+ ### Example
+ 
+ To filter the layer to include only the features whose `index` attribute is 5
+ or 10 and whose `ele` attribute is at least 1,500, you could create an
+ `NSCompoundPredicate` along these lines:
+ 
+ ```swift
+ let layer = MGLLineStyleLayer(identifier: "contour", source: terrain)
+ layer.sourceLayerIdentifier = "contours"
+ layer.predicate = NSPredicate(format: "(index == 5 || index == 10) && ele >= 1500.0")
+ mapView.style.addLayer(layer)
+ ```
  */
 @property (nonatomic, nullable) NSPredicate *predicate;
 
diff --git a/platform/darwin/test/MGLDocumentationExampleTests.swift b/platform/darwin/test/MGLDocumentationExampleTests.swift
new file mode 100644
index 0000000000..9243924328
--- /dev/null
+++ b/platform/darwin/test/MGLDocumentationExampleTests.swift
@@ -0,0 +1,209 @@
+import XCTest
+import Mapbox
+#if os(iOS)
+    import UIKit
+#else
+    import Cocoa
+#endif
+
+/**
+ Test cases that ensure the inline examples in the project documentation
+ compile.
+
+ To add an example:
+ 1. Add a test case named in the form testMGLClass or testMGLClass$method.
+ 2. Wrap the code you'd like to appear in the documentation within the
+    following comment blocks:
+    ```
+    //#-example-code
+    ...
+    //#-end-example-code
+    ```
+ 3. Insert an empty Swift code block inside the header file where you'd like the
+    example code to be inserted.
+ 4. Run `make darwin-update-examples` to extract example code from the test
+    method below and insert it into the header.
+ */
+class MGLDocumentationExampleTests: XCTestCase, MGLMapViewDelegate {
+    var mapView: MGLMapView!
+    var styleLoadingExpectation: XCTestExpectation!
+
+    override func setUp() {
+        super.setUp()
+        let styleURL = Bundle(for: MGLDocumentationExampleTests.self).url(forResource: "one-liner", withExtension: "json")
+        mapView = MGLMapView(frame: CGRect(x: 0, y: 0, width: 256, height: 256), styleURL: styleURL)
+        mapView.delegate = self
+        styleLoadingExpectation = expectation(description: "Map view should finish loading style")
+        waitForExpectations(timeout: 1, handler: nil)
+    }
+
+    override func tearDown() {
+        mapView = nil
+        styleLoadingExpectation = nil
+        super.tearDown()
+    }
+    
+    func mapView(_ mapView: MGLMapView, didFinishLoading style: MGLStyle) {
+        styleLoadingExpectation.fulfill()
+    }
+
+    func testMGLShapeSource() {
+        //#-example-code
+        var coordinates: [CLLocationCoordinate2D] = [
+            CLLocationCoordinate2D(latitude: 37.77, longitude: -122.42),
+            CLLocationCoordinate2D(latitude: 38.91, longitude: -77.04),
+        ]
+        let polyline = MGLPolylineFeature(coordinates: &coordinates, count: UInt(coordinates.count))
+        let shape = MGLShapeCollectionFeature(shapes: [polyline])
+        let source = MGLShapeSource(identifier: "lines", shape: shape, options: nil)
+        mapView.style.addSource(source)
+        //#-end-example-code
+
+        XCTAssertNotNil(mapView.style.source(withIdentifier: "lines"))
+    }
+
+    func testMGLRasterSource() {
+        //#-example-code
+        let source = MGLRasterSource(identifier: "clouds", tileURLTemplates: ["https://example.com/raster-tiles/{z}/{x}/{y}.png"], options: [
+            .minimumZoomLevel: 9,
+            .maximumZoomLevel: 16,
+            .tileSize: 512,
+            .attributionInfos: [
+                MGLAttributionInfo(title: NSAttributedString(string: "© Mapbox"), url: URL(string: "http://mapbox.com"))
+            ]
+        ])
+        mapView.style.addSource(source)
+        //#-end-example-code
+
+        XCTAssertNotNil(mapView.style.source(withIdentifier: "clouds"))
+    }
+
+    func testMGLVectorSource() {
+        //#-example-code
+        let source = MGLVectorSource(identifier: "pois", tileURLTemplates: ["https://example.com/vector-tiles/{z}/{x}/{y}.mvt"], options: [
+            .minimumZoomLevel: 9,
+            .maximumZoomLevel: 16,
+            .attributionInfos: [
+                MGLAttributionInfo(title: NSAttributedString(string: "© Mapbox"), url: URL(string: "http://mapbox.com"))
+            ]
+        ])
+        mapView.style.addSource(source)
+        //#-end-example-code
+
+        XCTAssertNotNil(mapView.style.source(withIdentifier: "pois"))
+    }
+
+    func testMGLCircleStyleLayer() {
+        let population = MGLVectorSource(identifier: "population", configurationURL: URL(string: "https://example.com/style.json")!)
+        mapView.style.addSource(population)
+        
+        //#-example-code
+        let layer = MGLCircleStyleLayer(identifier: "circles", source: population)
+        layer.sourceLayerIdentifier = "population"
+        layer.circleColor = MGLStyleValue(rawValue: .green)
+        layer.circleRadius = MGLStyleValue(interpolationBase: 1.75, stops: [
+            12: MGLStyleValue(rawValue: 2),
+            22: MGLStyleValue(rawValue: 180)
+        ])
+        layer.circleOpacity = MGLStyleValue(rawValue: 0.7)
+        layer.predicate = NSPredicate(format: "%K == %@", "marital-status", "married")
+        mapView.style.addLayer(layer)
+        //#-end-example-code
+
+        XCTAssertNotNil(mapView.style.layer(withIdentifier: "circles"))
+    }
+
+    func testMGLLineStyleLayer() {
+        let trails = MGLVectorSource(identifier: "trails", configurationURL: URL(string: "https://example.com/style.json")!)
+        mapView.style.addSource(trails)
+
+        //#-example-code
+        let layer = MGLLineStyleLayer(identifier: "trails-path", source: trails)
+        layer.sourceLayerIdentifier = "trails"
+        layer.lineWidth = MGLStyleValue(interpolationBase: 1.5, stops: [
+            14: MGLStyleValue(rawValue: 2),
+            18: MGLStyleValue(rawValue: 20),
+        ])
+        layer.lineColor = MGLStyleValue(rawValue: .brown)
+        layer.lineCap = MGLStyleValue(rawValue: NSValue(mglLineCap: .round))
+        layer.predicate = NSPredicate(format: "%K == %@", "trail-type", "mountain-biking")
+        mapView.style.addLayer(layer)
+        //#-end-example-code
+
+        XCTAssertNotNil(mapView.style.layer(withIdentifier: "trails-path"))
+    }
+
+    func testMGLFillStyleLayer() {
+        let parks = MGLVectorSource(identifier: "parks", configurationURL: URL(string: "https://example.com/style.json")!)
+        mapView.style.addSource(parks)
+
+        //#-example-code
+        let layer = MGLFillStyleLayer(identifier: "parks", source: parks)
+        layer.sourceLayerIdentifier = "parks"
+        layer.fillColor = MGLStyleValue(rawValue: .green)
+        layer.predicate = NSPredicate(format: "type == %@", "national-park")
+        mapView.style.addLayer(layer)
+        //#-end-example-code
+
+        XCTAssertNotNil(mapView.style.layer(withIdentifier: "parks"))
+    }
+
+    func testMGLSymbolStyleLayer() {
+        let pois = MGLVectorSource(identifier: "pois", configurationURL: URL(string: "https://example.com/style.json")!)
+        mapView.style.addSource(pois)
+
+        //#-example-code
+        let layer = MGLSymbolStyleLayer(identifier: "coffeeshops", source: pois)
+        layer.sourceLayerIdentifier = "pois"
+        layer.iconImageName = MGLStyleValue(rawValue: "coffee")
+        layer.iconScale = MGLStyleValue(rawValue: 0.5)
+        layer.textField = MGLStyleValue(rawValue: "{name}")
+        #if os(macOS)
+            var vector = CGVector(dx: 10, dy: 0)
+            layer.textTranslate = MGLStyleValue(rawValue: NSValue(bytes: &vector, objCType: "{CGVector=dd}"))
+        #else
+            layer.textTranslate = MGLStyleValue(rawValue: NSValue(cgVector: CGVector(dx: 10, dy: 0)))
+        #endif
+        layer.textJustification = MGLStyleValue(rawValue: NSValue(mglTextJustification: .left))
+        layer.textAnchor = MGLStyleValue(rawValue: NSValue(mglTextAnchor: .left))
+        layer.predicate = NSPredicate(format: "%K == %@", "venue-type", "coffee")
+        mapView.style.addLayer(layer)
+        //#-end-example-code
+
+        XCTAssertNotNil(mapView.style.layer(withIdentifier: "coffeeshops"))
+    }
+
+    func testMGLRasterStyleLayer() {
+        let source = MGLRasterSource(identifier: "clouds", tileURLTemplates: ["https://example.com/raster-tiles/{z}/{x}/{y}.png"], options: [
+            .minimumZoomLevel: 9,
+            .maximumZoomLevel: 16,
+            .tileSize: 512,
+            .attributionInfos: [
+                MGLAttributionInfo(title: NSAttributedString(string: "© Mapbox"), url: URL(string: "http://mapbox.com"))
+            ]
+        ])
+        mapView.style.addSource(source)
+
+        //#-example-code
+        let layer = MGLRasterStyleLayer(identifier: "clouds", source: source)
+        layer.rasterOpacity = MGLStyleValue(rawValue: 0.5)
+        mapView.style.addLayer(layer)
+        //#-end-example-code
+
+        XCTAssertNotNil(mapView.style.layer(withIdentifier: "clouds"))
+    }
+
+    func testMGLVectorStyleLayer$predicate() {
+        let terrain = MGLVectorSource(identifier: "terrain", configurationURL: URL(string: "https://example.com/style.json")!)
+        mapView.style.addSource(terrain)
+
+        //#-example-code
+        let layer = MGLLineStyleLayer(identifier: "contour", source: terrain)
+        layer.sourceLayerIdentifier = "contours"
+        layer.predicate = NSPredicate(format: "(index == 5 || index == 10) && ele >= 1500.0")
+        mapView.style.addLayer(layer)
+        //#-end-example-code
+
+        XCTAssertNotNil(mapView.style.layer(withIdentifier: "contour"))
+    }
+}
diff --git a/platform/darwin/test/MGLStyleLayerTests.m b/platform/darwin/test/MGLStyleLayerTests.m
index 590d6eda7f..66bdc0df0b 100644
--- a/platform/darwin/test/MGLStyleLayerTests.m
+++ b/platform/darwin/test/MGLStyleLayerTests.m
@@ -10,6 +10,7 @@
 
 - (void)setUp {
     [super setUp];
+    [MGLAccountManager setAccessToken:@"pk.feedcafedeadbeefbadebede"];
 #if TARGET_OS_IPHONE
     UIApplication *app = [UIApplication sharedApplication];
     UIViewController *vc = [[UIViewController alloc] init];
@@ -19,12 +20,17 @@
     [vc.view addSubview:_mapView];
     _mapView.delegate = self;
 #else
-    [MGLAccountManager setAccessToken:@"pk.feedcafedeadbeefbadebede"];
     NSWindowController *windowController = [[NSWindowController alloc] initWithWindowNibName:@"MGLStyleLayerTests" owner:self];
     [windowController showWindow:nil];
 #endif
 }
 
+- (void)tearDown {
+    _mapView = nil;
+    
+    [super tearDown];
+}
+
 - (void)testPropertyName:(NSString *)name isBoolean:(BOOL)isBoolean {
     NS_MUTABLE_ARRAY_OF(NSString *) *components = [name componentsSeparatedByString:@"-"].mutableCopy;
     if (isBoolean) {
diff --git a/platform/darwin/test/MGLStyleTests.mm b/platform/darwin/test/MGLStyleTests.mm
index 55a5df08ca..bcad7ab508 100644
--- a/platform/darwin/test/MGLStyleTests.mm
+++ b/platform/darwin/test/MGLStyleTests.mm
@@ -1,3 +1,4 @@
+#import "MGLAccountManager.h"
 #import "MGLMapView.h"
 #import "MGLStyle_Private.h"
 #import "MGLOpenGLStyleLayer.h"
@@ -36,9 +37,19 @@
 
 - (void)setUp {
     [super setUp];
-
+    
+    [MGLAccountManager setAccessToken:@"pk.feedcafedeadbeefbadebede"];
     self.mapView = [[MGLMapView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
-    self.style = [[MGLStyle alloc] initWithMapView:self.mapView];
+}
+
+- (void)tearDown {
+    self.mapView = nil;
+    
+    [super tearDown];
+}
+
+- (MGLStyle *)style {
+    return self.mapView.style;
 }
 
 - (void)testUnversionedStyleURLs {
@@ -174,18 +185,18 @@
 - (void)testAddingLayersWithDuplicateIdentifiers {
     //Just some source
     MGLVectorSource *source = [[MGLVectorSource alloc] initWithIdentifier:@"my-source" configurationURL:[NSURL URLWithString:@"mapbox://mapbox.mapbox-terrain-v2"]];
-    [self.mapView.style addSource: source];
+    [self.style addSource: source];
     
     //Add initial layer
     MGLFillStyleLayer *initial = [[MGLFillStyleLayer alloc] initWithIdentifier:@"my-layer" source:source];
-    [self.mapView.style addLayer:initial];
+    [self.style addLayer:initial];
     
     //Try to add the duplicate
-    XCTAssertThrowsSpecificNamed([self.mapView.style addLayer:[[MGLFillStyleLayer alloc] initWithIdentifier:@"my-layer" source:source]], NSException, @"MGLRedundantLayerIdentifierException");
-    XCTAssertThrowsSpecificNamed([self.mapView.style insertLayer:[[MGLFillStyleLayer alloc] initWithIdentifier:@"my-layer" source:source] belowLayer:initial],NSException, @"MGLRedundantLayerIdentifierException");
-    XCTAssertThrowsSpecificNamed([self.mapView.style insertLayer:[[MGLFillStyleLayer alloc] initWithIdentifier:@"my-layer" source:source] aboveLayer:initial], NSException, @"MGLRedundantLayerIdentifierException");
-    XCTAssertThrowsSpecificNamed([self.mapView.style insertLayer:[[MGLFillStyleLayer alloc] initWithIdentifier:@"my-layer" source:source] atIndex:0], NSException, @"MGLRedundantLayerIdentifierException");
-    XCTAssertThrowsSpecificNamed([self.mapView.style insertLayer:[[MGLOpenGLStyleLayer alloc] initWithIdentifier:@"my-layer"] atIndex:0], NSException, @"MGLRedundantLayerIdentifierException");
+    XCTAssertThrowsSpecificNamed([self.style addLayer:[[MGLFillStyleLayer alloc] initWithIdentifier:@"my-layer" source:source]], NSException, @"MGLRedundantLayerIdentifierException");
+    XCTAssertThrowsSpecificNamed([self.style insertLayer:[[MGLFillStyleLayer alloc] initWithIdentifier:@"my-layer" source:source] belowLayer:initial],NSException, @"MGLRedundantLayerIdentifierException");
+    XCTAssertThrowsSpecificNamed([self.style insertLayer:[[MGLFillStyleLayer alloc] initWithIdentifier:@"my-layer" source:source] aboveLayer:initial], NSException, @"MGLRedundantLayerIdentifierException");
+    XCTAssertThrowsSpecificNamed([self.style insertLayer:[[MGLFillStyleLayer alloc] initWithIdentifier:@"my-layer" source:source] atIndex:0], NSException, @"MGLRedundantLayerIdentifierException");
+    XCTAssertThrowsSpecificNamed([self.style insertLayer:[[MGLOpenGLStyleLayer alloc] initWithIdentifier:@"my-layer"] atIndex:0], NSException, @"MGLRedundantLayerIdentifierException");
 }
 
 - (NSString *)stringWithContentsOfStyleHeader {
@@ -209,8 +220,8 @@
 #endif
     XCTAssertNotNil(image);
     
-    [self.mapView.style setImage:image forName:imageName];
-    MGLImage *styleImage = [self.mapView.style imageForName:imageName];
+    [self.style setImage:image forName:imageName];
+    MGLImage *styleImage = [self.style imageForName:imageName];
     
     XCTAssertNotNil(styleImage);
     XCTAssertEqual(image.size.width, styleImage.size.width);
@@ -218,29 +229,27 @@
 }
 
 - (void)testLayersOrder {
-    [self.mapView setStyleURL:[MGLStyle streetsStyleURLWithVersion:8]];
-    
     NSString *filePath = [[NSBundle bundleForClass:self.class] pathForResource:@"amsterdam" ofType:@"geojson"];
     NSURL *url = [NSURL fileURLWithPath:filePath];
     MGLShapeSource *source = [[MGLShapeSource alloc] initWithIdentifier:@"sourceID" URL:url options:nil];
-    [self.mapView.style addSource:source];
+    [self.style addSource:source];
     
     MGLCircleStyleLayer *layer1 = [[MGLCircleStyleLayer alloc] initWithIdentifier:@"layer1" source:source];
-    [self.mapView.style addLayer:layer1];
+    [self.style addLayer:layer1];
     
     MGLCircleStyleLayer *layer3 = [[MGLCircleStyleLayer alloc] initWithIdentifier:@"layer3" source:source];
-    [self.mapView.style addLayer:layer3];
+    [self.style addLayer:layer3];
     
     MGLCircleStyleLayer *layer2 = [[MGLCircleStyleLayer alloc] initWithIdentifier:@"layer2" source:source];
-    [self.mapView.style insertLayer:layer2 aboveLayer:layer1];
+    [self.style insertLayer:layer2 aboveLayer:layer1];
     
     MGLCircleStyleLayer *layer4 = [[MGLCircleStyleLayer alloc] initWithIdentifier:@"layer4" source:source];
-    [self.mapView.style insertLayer:layer4 aboveLayer:layer3];
+    [self.style insertLayer:layer4 aboveLayer:layer3];
     
     MGLCircleStyleLayer *layer0 = [[MGLCircleStyleLayer alloc] initWithIdentifier:@"layer0" source:source];
-    [self.mapView.style insertLayer:layer0 belowLayer:layer1];
+    [self.style insertLayer:layer0 belowLayer:layer1];
     
-    NSArray<MGLStyleLayer *> *layers = [self.mapView.style layers];
+    NSArray<MGLStyleLayer *> *layers = [self.style layers];
     
     XCTAssert([[layers[0] identifier] isEqualToString:layer0.identifier]);
     XCTAssert([[layers[1] identifier] isEqualToString:layer1.identifier]);
diff --git a/platform/darwin/test/one-liner.json b/platform/darwin/test/one-liner.json
new file mode 100644
index 0000000000..23c546181f
--- /dev/null
+++ b/platform/darwin/test/one-liner.json
@@ -0,0 +1 @@
+{"version":8,"sources":{},"layers":[]}
\ No newline at end of file