UX: only apply link formats on paste to selections that do not contain bbcode-like tags (#15204)

app/assets/javascripts/discourse/app/mixins/textarea-text-manipulation.js

@@ -286,7 +286,10 @@ export default Mixin.create({
       plainText &&
       !handled &&
       selected.end > selected.start &&
-      !this._cachedLinkify.test(selectedValue)
+      // text selection does not contain url
+      !this._cachedLinkify.test(selectedValue) &&
+      // text selection does not contain a bbcode-like tag
+      !selectedValue.match(/\[\/?[a-z =]+?\]/g)
     ) {
       if (this._cachedLinkify.test(plainText)) {
         const match = this._cachedLinkify.match(plainText)[0];

app/assets/javascripts/discourse/tests/integration/components/d-editor-test.js

@@ -846,6 +846,19 @@ third line`
     }
   );
 
+  testCase(
+    `pasting a url onto a selection that contains bbcode-like tags will use default paste behavior`,
+    async function (assert, textarea) {
+      this.set("value", "hello [url=foobar]foobar[/url]");
+      setTextareaSelection(textarea, 0, 30);
+      const element = query(".d-editor");
+      const event = await paste(element, "https://www.discourse.com/");
+      // Synthetic paste events do not manipulate document content.
+      assert.strictEqual(this.value, "hello [url=foobar]foobar[/url]");
+      assert.strictEqual(event.defaultPrevented, false);
+    }
+  );
+
   (() => {
     // Tests to check cursor/selection after replace-text event.
     const BEFORE = "red green blue";