From db26ea218ca5c5aa9b5f839310ff93c12f0f6010 Mon Sep 17 00:00:00 2001
From: webzwo0i <webzwo0i@c3d2.de>
Date: Mon, 28 Dec 2020 21:53:08 +0100
Subject: [PATCH] page up/down: add test coverage

---
 tests/frontend/helper/methods.js   | 61 ++++++++++++++++++++++++++++++
 tests/frontend/specs/pageupdown.js | 52 +++++++++++++++++++++++++
 2 files changed, 113 insertions(+)
 create mode 100644 tests/frontend/specs/pageupdown.js

diff --git a/tests/frontend/helper/methods.js b/tests/frontend/helper/methods.js
index 4c7fe1204..05efcde92 100644
--- a/tests/frontend/helper/methods.js
+++ b/tests/frontend/helper/methods.js
@@ -236,3 +236,64 @@ helper.clearPad = async () => {
   await helper.waitForPromise(helper.padIsEmpty);
   await helper.waitForPromise(() => helper.commits.length > commitsBefore);
 };
+
+/**
+ * Scrolls up in the editor
+ * TODO: is `getSelection` always defined?
+ */
+helper.pageUp = async () => {
+  // the caret is in this node
+  const caretNode = helper.padInner$.document.getSelection().anchorNode;
+  const event = new helper.padInner$.Event(helper.evtType);
+  event.which = 33;
+  helper.padInner$('#innerdocbody').trigger(event);
+
+  // return as soon as the selection has changed
+  await helper.waitForPromise(() => helper.padInner$.document.getSelection().anchorNode !== caretNode);
+};
+
+/**
+ * Scrolls down in the editor
+ * TODO: is `getSelection` always defined?
+ */
+helper.pageDown = async () => {
+  // the caret is in this node
+  const caretNode = helper.padInner$.document.getSelection().anchorNode;
+  const event = new helper.padInner$.Event(helper.evtType);
+  event.which = 34;
+  helper.padInner$('#innerdocbody').trigger(event);
+
+  // return as soon as the selection has changed
+  await helper.waitForPromise(() => helper.padInner$.document.getSelection().anchorNode !== caretNode);
+};
+
+/**
+ * Gets the line number where the caret is currently in
+ *
+ * @returns {number} line number
+ */
+helper.caretLineNumber = () => {
+  if (helper.padInner$.document.getSelection()) {
+    let caretNode = helper.padInner$.document.getSelection().anchorNode;;
+    let bodyElement = helper.padInner$('body')[0];
+
+    // a text node does not have a classList method
+    if (caretNode.nodeType === 3) {
+      caretNode = caretNode.parentNode;
+    }
+
+    // find the ace-line that contains the caret
+    while (!caretNode.classList.contains('ace-line') && caretNode !== bodyElement ) {
+      caretNode = caretNode.parentNode;
+
+      // a text node does not have a classList method
+      if (caretNode.nodeType === 3) {
+        caretNode = caretNode.parentNode;
+      }
+    }
+
+    // find the index of that line in the array of all lines
+    const lines = helper.linesDiv().map((line) => line[0]);
+    return lines.indexOf(caretNode) + 1;
+  }
+};
diff --git a/tests/frontend/specs/pageupdown.js b/tests/frontend/specs/pageupdown.js
new file mode 100644
index 000000000..7a58c2201
--- /dev/null
+++ b/tests/frontend/specs/pageupdown.js
@@ -0,0 +1,52 @@
+'use strict';
+
+describe('Page Up/Down', function () {
+  beforeEach(function (cb) {
+    helper.newPad({
+      cb: async () => {
+        await helper.clearPad();
+        // 200 lines
+        await helper.edit(
+          '\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n' +
+          '\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n' +
+          '\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n' +
+          '\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n' +
+          '\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n');
+        cb()
+      }
+    });
+  });
+
+  // scrolls up 3 times
+  it('scrolls up on key stroke', async function(){
+    let currentLineNumber = helper.caretLineNumber();
+    helper.pageUp();
+    await helper.waitForPromise(() => currentLineNumber > helper.caretLineNumber());
+
+    currentLineNumber = helper.caretLineNumber();
+    helper.pageUp();
+    await helper.waitForPromise(() => currentLineNumber > helper.caretLineNumber());
+
+    currentLineNumber = helper.caretLineNumber();
+    helper.pageUp();
+    await helper.waitForPromise(() => currentLineNumber > helper.caretLineNumber());
+  })
+
+  // scrolls down 3 times
+  it('scrolls down on key stroke', async function(){
+    // this places the caret in the first line
+    await helper.edit('Line 1', 1);
+
+    let currentLineNumber = helper.caretLineNumber();
+    helper.pageDown();
+    await helper.waitForPromise(() => currentLineNumber < helper.caretLineNumber());
+
+    currentLineNumber = helper.caretLineNumber();
+    helper.pageDown();
+    await helper.waitForPromise(() => currentLineNumber < helper.caretLineNumber());
+
+    currentLineNumber = helper.caretLineNumber();
+    helper.pageDown();
+    await helper.waitForPromise(() => currentLineNumber < helper.caretLineNumber());
+  })
+})