Fix issue with double escaped autolink special characters

CHANGES.md

@@ -20,6 +20,7 @@ New Features:
 * [#4807](https://github.com/ckeditor/ckeditor4/issues/4807): [Chrome] Improve the performance of pasting large images. Thanks to [FlowIT-JIT](https://github.com/FlowIT-JIT)!
 * [#4850](https://github.com/ckeditor/ckeditor4/issues/4850): Added support for loading [content templates](https://ckeditor.com/cke4/addon/templates) from HTML files. Thanks to [Fynn96](https://github.com/Fynn96)!
 * [#4874](https://github.com/ckeditor/ckeditor4/issues/4874): Added the [`config.clipboard_handleImages`](https://ckeditor.com/docs/ckeditor4/latest/api/CKEDITOR_config.html#cfg-clipboard_handleImages) configuration option for enabling and disabling built-in support for pasting and dropping images in the [Clipboard](https://ckeditor.com/cke4/addon/clipboard) plugin. Thanks to [FlowIT-JIT](https://github.com/FlowIT-JIT)!
+* [#4858](https://github.com/ckeditor/ckeditor4/issues/4858): Fixed: [Autolink](https://ckeditor.com/cke4/addon/autolink) plugin incorrectly escapes `&` characters when pasting links into the editor.
 
 Fixed Issues:
 

plugins/autolink/plugin.js

@@ -74,6 +74,10 @@
 			}
 
 			function getHtmlToInsert( text ) {
+				// URL will be encoded later on with link.setAttribute method. Avoid
+				// double encoding of special characters (#4858).
+				text = CKEDITOR.tools.htmlDecodeAttr( text );
+
 				var link = new CKEDITOR.dom.element( 'a' ),
 					value = text.replace( /"/g, '%22' );
 

tests/plugins/autolink/autolink.js

@@ -99,6 +99,20 @@
 			assertPasteEvent( this.editors.classic, { dataValue: pastedText }, { dataValue: pastedText, type: 'html' } );
 		},
 
+		// (#4858)
+		'test URL link with encoded characters': function() {
+			var pastedText = 'https://www.google.com/test/?one=one&two=two&three',
+				expected = '<a href="https://www.google.com/test/?one=one&amp;two=two&amp;three">https://www.google.com/test/?one=one&amp;two=two&amp;three</a>',
+				spy = sinon.spy( CKEDITOR.tools, 'htmlDecodeAttr' );
+
+			assertPasteEvent( this.editors.classic, { dataValue: pastedText }, { dataValue: expected, type: 'html' } );
+
+			spy.restore();
+
+			// Ensure that the test is correct.
+			assert.isTrue( spy.calledWithExactly( pastedText ), 'htmlDecodeAttr was called with incorrect input' );
+		},
+
 		'test mail link with text after': function() {
 			var pastedText = 'mail@example.com nope';
 

tests/plugins/autolink/manual/encoding.html

@@ -0,0 +1,17 @@
+<h3>URLs that should be turned into links</h3>
+
+<style>
+input[type=text] { width: 450px }
+</style>
+
+<input type="text" readonly="readonly" value="https://www.google.com/test/?one=one&two=two&three">
+
+<textarea id="editor" cols="10" rows="10">
+	<p>Foo bar.</p>
+</textarea>
+
+<script>
+	bender.tools.ignoreUnsupportedEnvironment( 'autolink' );
+
+	CKEDITOR.replace( 'editor' );
+</script>

tests/plugins/autolink/manual/encoding.md

@@ -0,0 +1,17 @@
+@bender-ui: collapsed
+@bender-tags: 4.17.0, bug, 4858
+@bender-ckeditor-plugins: clipboard, toolbar, wysiwygarea, elementspath, autolink, sourcearea, htmlwriter
+
+Paste the given URL to the editor and check whether it's turned into a link. Make sure to also confirm links in source area.
+
+## Expected
+
+**Editor:** Link is pasted as it is, without additional encoding.
+
+**Source area:** `&` characters are single encoded with `&`.
+
+## Unexpected
+
+**Editor:** Special `&` characters are additionaly encoded to `&`.
+
+**Source area:** `&` characters are double encoded to `&`.