Ticket #37690: 37690.1.patch

src/wp-admin/js/editor-expand.js

@@ -16 +16 @@
                         $textTop = $( '#ed_toolbar' ),
                         $textEditor = $( '#content' ),
                         textEditor = $textEditor[0],
+                        $textEditorClone = $textEditor.clone().attr({ id: 'content-clone', name: null }),
+                        textEditorClone = $textEditorClone[0],
                         oldTextLength = 0,
                         $bottom = $( '#post-status-info' ),
                         $menuBar = $(),
@@ -53 +55 @@
                                 sideSortablesHeight: 0
                         };
 
+                var shrinkTextarea = window._.throttle( function() {
+                        var top = window.scrollTop;
+                        var height = parseInt( textEditor.style.height, 10 );
+
+                        textEditorClone.value = textEditor.value;
+
+                        if ( textEditorClone.scrollHeight > autoresizeMinHeight ) {
+                                textEditor.style.height = textEditorClone.scrollHeight + 'px';
+                        } else if ( textEditorClone.scrollHeight < height ) {
+                                textEditor.style.height = autoresizeMinHeight + 'px';
+                        }
+
+                        // Prevent scroll-jumping in Firefox and IE.
+                        window.scrollTop = top;
+
+                        if ( textEditor.scrollHeight < height ) {
+                                adjust();
+                        }
+                }, 500 );
+
+                function textEditorResize() {
+                        var length = textEditor.value.length;
+
+                        if ( mceEditor && ! mceEditor.isHidden() ) {
+                                return;
+                        }
+
+                        if ( ! mceEditor && initialMode === 'tinymce' ) {
+                                return;
+                        }
+
+                        if ( length < oldTextLength ) {
+                                shrinkTextarea();
+                        } else if ( parseInt( textEditor.style.height, 10 ) < textEditor.scrollHeight ) {
+                                textEditor.style.height = Math.ceil( textEditor.scrollHeight ) + 'px';
+                                adjust();
+                        }
+
+                        oldTextLength = length;
+                }
+
                 function getHeights() {
                         var windowWidth = $window.width();
 
@@ -75 +118 @@
                         }
                 }
 
-                function textEditorResize() {
-                        if ( mceEditor && ! mceEditor.isHidden() ) {
-                                return;
-                        }
+                // Append the cloned textarea after the "real" one and move it off screen.
+                $textEditor.after( $textEditorClone.css({ position: 'absolute', left: '-10000em' }) );
 
-                        if ( ! mceEditor && initialMode === 'tinymce' ) {
-                                return;
-                        }
-
-                        var length = textEditor.value.length;
-                        var height = parseInt( textEditor.style.height, 10 );
-                        var top = window.scrollTop;
-
-                        if ( length < oldTextLength ) {
-                                // textEditor.scrollHeight is not adjusted until the next line.
-                                textEditor.style.height = 'auto';
-
-                                if ( textEditor.scrollHeight > autoresizeMinHeight ) {
-                                        textEditor.style.height = textEditor.scrollHeight + 'px';
-                                } else {
-                                        textEditor.style.height = autoresizeMinHeight + 'px';
-                                }
-
-                                // Prevent scroll-jumping in Firefox and IE.
-                                window.scrollTop = top;
-
-                                if ( textEditor.scrollHeight < height ) {
-                                        adjust();
-                                }
-                        } else if ( height < textEditor.scrollHeight ) {
-                                textEditor.style.height = textEditor.scrollHeight + 'px';
-                                adjust();
-                        }
-
-                        oldTextLength = length;
-                }
-
                 // We need to wait for TinyMCE to initialize.
                 $document.on( 'tinymce-editor-init.editor-expand', function( event, editor ) {
                         var VK = window.tinymce.util.VK,

src/wp-includes/script-loader.php

@@ -563 +563 @@
                         'suggestedImgAlt' => __( 'Suggested image #%d' ),
                 ) );
 
-                $scripts->add( 'editor-expand', "/wp-admin/js/editor-expand$suffix.js", array( 'jquery' ), false, 1 );
+                $scripts->add( 'editor-expand', "/wp-admin/js/editor-expand$suffix.js", array( 'jquery', 'underscore' ), false, 1 );
 
                 $scripts->add( 'link', "/wp-admin/js/link$suffix.js", array( 'wp-lists', 'postbox' ), false, 1 );