Merge pull request #8868 from ahocevar/abstract-methods

Throw when calling abstract methods; fix abstract return types

src/ol/source/Image.js

@@ -1,8 +1,8 @@
 /**
  * @module ol/source/Image
  */
+import {abstract} from '../util.js';
 import {ENABLE_RASTER_REPROJECTION} from '../reproj/common.js';
-
 import ImageState from '../ImageState.js';
 import {linearFindNearest} from '../array.js';
 import Event from '../events/Event.js';
@@ -81,6 +81,7 @@ class ImageSourceEvent extends Event {
  * Abstract base class; normally only used for creating subclasses and not
  * instantiated in apps.
  * Base class for sources providing a single image.
+ * @abstract
  * @api
  */
 class ImageSource extends Source {
@@ -188,7 +189,9 @@ class ImageSource extends Source {
    * @return {import("../ImageBase.js").default} Single image.
    * @protected
    */
-  getImageInternal(extent, resolution, pixelRatio, projection) {}
+  getImageInternal(extent, resolution, pixelRatio, projection) {
+    return abstract();
+  }
 
   /**
    * Handle image change events.

src/ol/source/Source.js

@@ -1,7 +1,7 @@
 /**
  * @module ol/source/Source
  */
-
+import {abstract} from '../util.js';
 import BaseObject from '../Object.js';
 import {get as getProjection} from '../proj.js';
 import SourceState from './State.js';
@@ -44,6 +44,7 @@ import SourceState from './State.js';
  * Base class for {@link module:ol/layer/Layer~Layer} sources.
  *
  * A generic `change` event is triggered when the state of the source changes.
+ * @abstract
  * @api
  */
 class Source extends BaseObject {
@@ -123,7 +124,9 @@ class Source extends BaseObject {
    * @abstract
    * @return {Array<number>|undefined} Resolutions.
    */
-  getResolutions() {}
+  getResolutions() {
+    return abstract();
+  }
 
   /**
    * Get the state of the source, see {@link module:ol/source/State~State} for possible states.

src/ol/source/Tile.js

@@ -1,7 +1,7 @@
 /**
  * @module ol/source/Tile
  */
-
+import {abstract} from '../util.js';
 import TileCache from '../TileCache.js';
 import TileState from '../TileState.js';
 import Event from '../events/Event.js';
@@ -31,6 +31,7 @@ import {wrapX, getForProjection as getTileGridForProjection} from '../tilegrid.j
  * Abstract base class; normally only used for creating subclasses and not
  * instantiated in apps.
  * Base class for sources providing images divided into a tile grid.
+ * @abstract
  * @api
  */
 class TileSource extends Source {
@@ -199,7 +200,9 @@ class TileSource extends Source {
    * @param {import("../proj/Projection.js").default} projection Projection.
    * @return {!import("../Tile.js").default} Tile.
    */
-  getTile(z, x, y, pixelRatio, projection) {}
+  getTile(z, x, y, pixelRatio, projection) {
+    return abstract();
+  }
 
   /**
    * Return the tile grid of the tile source.
@@ -292,8 +295,8 @@ class TileSource extends Source {
   }
 
   /**
-   * @abstract
    * Marks a tile coord as being used, without triggering a load.
+   * @abstract
    * @param {number} z Tile coordinate z.
    * @param {number} x Tile coordinate x.
    * @param {number} y Tile coordinate y.