Fix customTextRenderer called more times than there are textContent items

Related to #1151

Author: wojtekmaj

README.md

@@ -405,7 +405,7 @@ Displays a page. Should be placed inside `<Document />`. Alternatively, it can h
 | canvasBackground         | Canvas background color. Any valid `canvas.fillStyle` can be used. If you set `renderMode` to `"svg"` this prop will be ignored.                                                                                                                                                                 | n/a                                           | `"transparent"`                                                                                                                                                                                                                                                                                  |
 | canvasRef                | A prop that behaves like [ref](https://reactjs.org/docs/refs-and-the-dom.html), but it's passed to `<canvas>` rendered by `<PageCanvas>` component. If you set `renderMode` to `"svg"` this prop will be ignored.                                                                                | n/a                                           | <ul><li>Function:<br />`(ref) => { this.myPage = ref; }`</li><li>Ref created using `React.createRef`:<br />`this.ref = React.createRef();`<br />…<br />`inputRef={this.ref}`</li><li>Ref created using `React.useRef`:<br />`const ref = React.useRef();`<br />…<br />`inputRef={ref}`</li></ul> |
 | className                | Class name(s) that will be added to rendered element along with the default `react-pdf__Page`.                                                                                                                                                                                                   | n/a                                           | <ul><li>String:<br />`"custom-class-name-1 custom-class-name-2"`</li><li>Array of strings:<br />`["custom-class-name-1", "custom-class-name-2"]`</li></ul>                                                                                                                                       |
-| customTextRenderer       | Function that customizes how a text layer is rendered.                                                                                                                                                                                                                                           | n/a                                           | `` ({ str, itemIndex }) => str && str.replace(/ipsum/g, `<mark>ipsum</mark>`) ``                                                                                                                                                                                                                 |
+| customTextRenderer       | Function that customizes how a text layer is rendered.                                                                                                                                                                                                                                           | n/a                                           | `` ({ str, itemIndex }) => str.replace(/ipsum/g, `<mark>ipsum</mark>`) ``                                                                                                                                                                                                                        |
 | error                    | What the component should display in case of an error.                                                                                                                                                                                                                                           | `"Failed to load the page."`                  | <ul><li>String:<br />`"An error occurred!"`</li><li>React element:<br />`<div>An error occurred!</div>`</li><li>Function:<br />`this.renderError`</li></ul>                                                                                                                                      |
 | height                   | Page height. If neither `height` nor `width` are defined, page will be rendered at the size defined in PDF. If you define `width` and `height` at the same time, `height` will be ignored. If you define `height` and `scale` at the same time, the height will be multiplied by a given factor. | Page's default height                         | `300`                                                                                                                                                                                                                                                                                            |
 | imageResourcesPath       | The path used to prefix the src attributes of annotation SVGs.                                                                                                                                                                                                                                   | n/a (pdf.js will fallback to an empty string) | `"/public/images/"`                                                                                                                                                                                                                                                                              |

src/Page/TextLayer.jsx

@@ -141,14 +141,18 @@ export class TextLayerInternal extends PureComponent {
     cancellable.promise
       .then(() => {
         if (customTextRenderer) {
-          Array.from(this.layerElement.current.children).forEach((element, elementIndex) => {
+          textContent.items.forEach((item, itemIndex) => {
+            const child = this.layerElement.current.children[itemIndex];
+
             const content = customTextRenderer({
-              itemIndex: elementIndex,
-              ...textContent.items[elementIndex],
+              itemIndex,
+              ...item,
             });
-            element.innerHTML = content;
+
+            child.innerHTML = content;
           });
         }
+
         this.onRenderSuccess();
       })
       .catch((error) => {

test/Test.jsx

@@ -183,7 +183,7 @@ export default function Test() {
       renderTextLayer,
       scale: pageScale,
       width: pageWidth,
-      customTextRenderer: ({ str }) => str && str.replace(/ipsum/g, `<mark>ipsum</mark>`),
+      customTextRenderer: ({ str }) => str.replace(/ipsum/g, `<mark>ipsum</mark>`),
     };
   }