1 files changed, 72 insertions, 0 deletions
diff --git a/toolkit/modules/tests/browser/browser_Finder_offscreen_text.js b/toolkit/modules/tests/browser/browser_Finder_offscreen_text.js
new file mode 100644
index 0000000000..4e1b7874a4
--- /dev/null
+++ b/toolkit/modules/tests/browser/browser_Finder_offscreen_text.js
@@ -0,0 +1,72 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+add_task(async function test_offscreen_text() {
+  // Generate URI of a big DOM that contains the target text at several
+  // line positions (to force some targets to be offscreen).
+  const linesToGenerate = 155;
+  const linesToInsertTargetText = [5, 50, 150];
+  let targetCount = linesToInsertTargetText.length;
+  let t = 0;
+  const TARGET_TEXT = "findthis";
+
+  let URI = "<body>";
+  for (let i = 0; i < linesToGenerate; i++) {
+    URI += i + "<br>";
+    if (t < targetCount && linesToInsertTargetText[t] == i) {
+      URI += TARGET_TEXT;
+      t++;
+    }
+  }
+  URI += "</body>";
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "data:text/html;charset=utf-8," + encodeURIComponent(URI),
+    },
+    async function(browser) {
+      let finder = browser.finder;
+      let listener = {
+        onFindResult() {
+          ok(false, "callback wasn't replaced");
+        },
+      };
+      finder.addResultListener(listener);
+
+      function waitForFind() {
+        return new Promise(resolve => {
+          listener.onFindResult = resolve;
+        });
+      }
+
+      // Find each of the targets.
+      for (let t = 0; t < targetCount; ++t) {
+        let promiseFind = waitForFind();
+        if (t == 0) {
+          finder.fastFind(TARGET_TEXT, false, false);
+        } else {
+          finder.findAgain(TARGET_TEXT, false, false, false);
+        }
+        let findResult = await promiseFind;
+        is(
+          findResult.result,
+          Ci.nsITypeAheadFind.FIND_FOUND,
+          "Found target " + t
+        );
+      }
+
+      // Find one more time and make sure we wrap.
+      let promiseFind = waitForFind();
+      finder.findAgain(TARGET_TEXT, false, false, false);
+      let findResult = await promiseFind;
+      is(
+        findResult.result,
+        Ci.nsITypeAheadFind.FIND_WRAPPED,
+        "Wrapped to first target"
+      );
+
+      finder.removeResultListener(listener);
+    }
+  );
+});