[change] Image 'source' dimensions and RN layout

Adds support for 'width' and 'height' set via the 'source' property.
Emulates RN image layout (i.e., no dimensions by default).

Fix #10

examples/components/Image/ImageExample.js

@@ -218,7 +218,7 @@ const examples = [
     render: function() {
       return (
         <Image
-          source={{uri: 'http://facebook.github.io/react/img/logo_og.png'}}
+          source={{ uri: 'http://facebook.github.io/react/img/logo_og.png', width: 1200, height: 630 }}
           style={styles.base}
         />
       );

src/components/Image/__tests__/index-test.js

@@ -34,8 +34,8 @@ suite('components/Image', () => {
     test('sets background image when value is an object', () => {
       const defaultSource = { uri: 'https://google.com/favicon.ico' };
       const image = shallow(<Image defaultSource={defaultSource} />);
-      const backgroundImage = StyleSheet.flatten(image.prop('style')).backgroundImage;
-      assert(backgroundImage.indexOf(defaultSource.uri) > -1);
+      const style = StyleSheet.flatten(image.prop('style'));
+      assert(style.backgroundImage.indexOf(defaultSource.uri) > -1);
     });
 
     test('sets background image when value is a string', () => {
@@ -45,13 +45,30 @@ suite('components/Image', () => {
       const backgroundImage = StyleSheet.flatten(image.prop('style')).backgroundImage;
       assert(backgroundImage.indexOf(defaultSource) > -1);
     });
+
+    test('sets "height" and "width" styles if missing', () => {
+      const defaultSource = { uri: 'https://google.com/favicon.ico', height: 10, width: 20 };
+      const image = mount(<Image defaultSource={defaultSource} />);
+      const html = image.html();
+      assert(html.indexOf('height: 10px') > -1);
+      assert(html.indexOf('width: 20px') > -1);
+    });
+
+    test('does not override "height" and "width" styles', () => {
+      const defaultSource = { uri: 'https://google.com/favicon.ico', height: 10, width: 20 };
+      const image = mount(<Image defaultSource={defaultSource} style={{ height: 20, width: 40 }} />);
+      const html = image.html();
+      assert(html.indexOf('height: 20px') > -1);
+      assert(html.indexOf('width: 40px') > -1);
+    });
   });
 
   test('prop "onError"', function (done) {
     this.timeout(5000);
-    mount(<Image onError={onError} source={{ uri: 'https://google.com/favicon.icox' }} />);
+    const image = mount(<Image onError={onError} source={{ uri: 'https://google.com/favicon.icox' }} />);
     function onError(e) {
-      assert.equal(e.nativeEvent.type, 'error');
+      assert.ok(e.nativeEvent.error);
+      image.unmount();
       done();
     }
   });
@@ -63,6 +80,7 @@ suite('components/Image', () => {
       assert.equal(e.nativeEvent.type, 'load');
       const hasBackgroundImage = (image.html()).indexOf('url(&quot;https://google.com/favicon.ico&quot;)') > -1;
       assert.equal(hasBackgroundImage, true);
+      image.unmount();
       done();
     }
   });
@@ -74,6 +92,7 @@ suite('components/Image', () => {
       assert.ok(true);
       const hasBackgroundImage = (image.html()).indexOf('url(&quot;https://google.com/favicon.ico&quot;)') > -1;
       assert.equal(hasBackgroundImage, true);
+      image.unmount();
       done();
     }
   });
@@ -121,10 +140,11 @@ suite('components/Image', () => {
 
     test('sets background image when value is an object', (done) => {
       const source = { uri: 'https://google.com/favicon.ico' };
-      mount(<Image onLoad={onLoad} source={source} />);
+      const image = mount(<Image onLoad={onLoad} source={source} />);
       function onLoad(e) {
         const src = e.nativeEvent.target.src;
         assert.equal(src, source.uri);
+        image.unmount();
         done();
       }
     });
@@ -132,10 +152,11 @@ suite('components/Image', () => {
     test('sets background image when value is a string', (done) => {
       // emulate require-ed asset
       const source = 'https://google.com/favicon.ico';
-      mount(<Image onLoad={onLoad} source={source} />);
+      const image = mount(<Image onLoad={onLoad} source={source} />);
       function onLoad(e) {
         const src = e.nativeEvent.target.src;
         assert.equal(src, source);
+        image.unmount();
         done();
       }
     });

src/components/Image/index.js

@@ -17,11 +17,20 @@ const STATUS_IDLE = 'IDLE';
 
 const ImageSourcePropType = PropTypes.oneOfType([
   PropTypes.shape({
-    uri: PropTypes.string.isRequired
+    height: PropTypes.number,
+    uri: PropTypes.string.isRequired,
+    width: PropTypes.number
   }),
   PropTypes.string
 ]);
 
+const resolveAssetDimensions = (source) => {
+  if (typeof source === 'object') {
+    const { height, width } = source;
+    return { height, width };
+  }
+};
+
 const resolveAssetSource = (source) => {
   return ((typeof source === 'object') ? source.uri : source) || null;
 };
@@ -93,12 +102,15 @@ class Image extends Component {
     } = this.props;
 
     const displayImage = resolveAssetSource(!isLoaded ? defaultSource : source);
+    const imageSizeStyle = resolveAssetDimensions(!isLoaded ? defaultSource : source);
     const backgroundImage = displayImage ? `url("${displayImage}")` : null;
-    const flatStyle = StyleSheet.flatten(this.props.style);
-    const resizeMode = this.props.resizeMode || flatStyle.resizeMode || ImageResizeMode.cover;
+    const originalStyle = StyleSheet.flatten(this.props.style);
+    const resizeMode = this.props.resizeMode || originalStyle.resizeMode || ImageResizeMode.cover;
+
     const style = StyleSheet.flatten([
       styles.initial,
-      flatStyle,
+      imageSizeStyle,
+      originalStyle,
       backgroundImage && { backgroundImage },
       resizeModeStyles[resizeMode]
     ]);
@@ -147,14 +159,18 @@ class Image extends Component {
     }
   }
 
-  _onError = (e) => {
-    const { onError } = this.props;
-    const event = { nativeEvent: e };
-
+  _onError = () => {
+    const { onError, source } = this.props;
     this._destroyImageLoader();
-    this._updateImageState(STATUS_ERRORED);
     this._onLoadEnd();
-    if (onError) { onError(event); }
+    this._updateImageState(STATUS_ERRORED);
+    if (onError) {
+      onError({
+        nativeEvent: {
+          error: `Failed to load resource ${resolveAssetSource(source)} (404)`
+        }
+      });
+    }
   }
 
   _onLoad = (e) => {
@@ -189,7 +205,6 @@ class Image extends Component {
 
 const styles = StyleSheet.create({
   initial: {
-    alignSelf: 'flex-start',
     backgroundColor: 'transparent',
     backgroundPosition: 'center',
     backgroundRepeat: 'no-repeat',