Issue ShinyChang#69 | Don't truncate if text fits into an element

This happens if the truncate-component if wrapped by a flex element, and that flex element only takes minimal required space to fix its content. The issue here is that `measureText` methods uses rounding, while width of the truncate component's ref is calculated without rounding. Removing rounding and applying good-enough floats comparison fixes the issue.
Casilio · Feb 21, 2022 · 8527eb2 · 8527eb2
1 parent 250b498
commit 8527eb2
Show file tree

Hide file tree

Showing 3 changed files with 30 additions and 10 deletions.
diff --git a/server.js b/server.js
@@ -5,6 +5,7 @@ var config = require('./webpack.config.dev');
 
 var app = express();
 var compiler = webpack(config);
+var PORT = 3000
 
 app.use(require('webpack-dev-middleware')(compiler, {
     noInfo: true,
@@ -17,11 +18,11 @@ app.get('*', function(req, res) {
     res.sendFile(path.join(__dirname, 'index.html'));
 });
 
-app.listen(3000, 'localhost', function(err) {
+app.listen(PORT, 'localhost', function(err) {
     if (err) {
         console.log(err);
         return;
     }
 
-    console.log('Listening at http://localhost:3000');
+    console.log(`Listening at http://localhost:${PORT}`);
 });
diff --git a/src/App.js b/src/App.js
@@ -214,6 +214,21 @@ export class App extends Component {
                             />
                         </div>
                     </div>
+                    <div id="sample-13">
+                        <h5>
+                            13. Issue{" "}
+                            <a href="https://github.com/ShinyChang/React-Text-Truncate/issues/69">
+                                #69
+                            </a>
+                        </h5>
+                        <div className="container">
+                            <TextTruncate
+                                line={1}
+                                truncateText="...trancated"
+                                text={"V3"}
+                            />
+                        </div>
+                    </div>
                 </div>
             </div>
         );

diff --git a/src/TextTruncate.js b/src/TextTruncate.js
@@ -1,6 +1,9 @@
 import React, {Component, createElement} from 'react';
 import PropTypes from 'prop-types';
 
+const PRECISION = 0.0001;
+const isEqual = (n1, n2) => Math.abs(n1 - n2) < PRECISION;
+
 export default class TextTruncate extends Component {
   static propTypes = {
     containerClassName: PropTypes.string,
@@ -54,7 +57,7 @@ export default class TextTruncate extends Component {
     if (this.rafId) {
       window.cancelAnimationFrame(this.rafId);
     }
-    this.rafId = window.requestAnimationFrame(this.update.bind(this))
+    this.rafId = window.requestAnimationFrame(this.update.bind(this));
   };
 
   onToggled = (truncated) => {
@@ -83,7 +86,7 @@ export default class TextTruncate extends Component {
   };
 
   measureWidth(text) {
-    return Math.ceil(this.canvas.measureText(text).width);
+    return this.canvas.measureText(text).width;
   }
 
   getRenderText() {
@@ -109,8 +112,9 @@ export default class TextTruncate extends Component {
       return null;
     }
 
+    const fullTextWidth = this.measureWidth(text);
     // return if all of text can be displayed
-    if (scopeWidth >= this.measureWidth(text)) {
+    if (scopeWidth > fullTextWidth || isEqual(scopeWidth, fullTextWidth)) {
       this.onToggled(false);
       return createElement(textElement, props, text);
     }
@@ -136,7 +140,7 @@ export default class TextTruncate extends Component {
     let lastSpaceIndex = -1;
     let ext = '';
     let loopCnt = 0;
-    
+
     while (displayLine-- > 0) {
       ext = displayLine ? '' : truncateText + (childText ? (' ' + childText) : '');
       while (currentPos <= maxTextLength) {
@@ -172,15 +176,15 @@ export default class TextTruncate extends Component {
                 }
                 truncatedText = text.substr(startPos, currentPos);
               } else {
-                currentPos--;  
+                currentPos--;
                 truncatedText = text.substr(startPos, currentPos);
               }
             } else {
               currentPos--;
               truncatedText = text.substr(startPos, currentPos);
             }
             width = this.measureWidth(truncatedText + ext);
-          } while (width >= scopeWidth && truncatedText.length > 0);
+          } while ((width > scopeWidth || isEqual(width, scopeWidth)) && truncatedText.length > 0);
           startPos += currentPos;
           break;
         }
@@ -202,7 +206,7 @@ export default class TextTruncate extends Component {
       this.onToggled(false);
       return createElement(textElement, props, text);
     }
-    
+
     this.onTruncated();
     this.onToggled(true);
     return (
@@ -232,7 +236,7 @@ export default class TextTruncate extends Component {
 
     const { fontWeight, fontStyle, fontSize, fontFamily } = style;
 
-    const renderText = this.scope && line ? this.getRenderText() : createElement(textElement, props, text);;
+    const renderText = this.scope && line ? this.getRenderText() : createElement(textElement, props, text);
     const rootProps = {
       ref: (el) => {this.scope = el},
       className: containerClassName,