Test handleTab

lib/__tests__/handle-tab.test.js

@@ -0,0 +1,59 @@
+const { EditorState, ContentState, SelectionState } = require('draft-js');
+const handleTab = require('../handleTab');
+
+const toPlainText = (editorState) => editorState.getCurrentContent().getPlainText();
+const createWithText = (text) => {
+  const contentState = ContentState.createFromText(text);
+  return EditorState.createWithContent(contentState);
+}
+
+const tabs = (times) => "    ".repeat(times || 1);
+
+it('should insert a tab', () => {
+  const evt = { preventDefault: jest.fn() };
+  const initialText = "";
+  const before = createWithText(initialText);
+  const after = handleTab(evt, before);
+
+  expect(toPlainText(before)).toEqual(initialText);
+  expect(toPlainText(after)).toEqual(tabs(1));
+});
+
+it('should prevent the default event behavior', () => {
+  const preventDefault = jest.fn();
+  const evt = { preventDefault };
+  const before = EditorState.createEmpty();
+
+  handleTab(evt, before);
+  expect(preventDefault).toHaveBeenCalled();
+})
+
+it('should add a tab to an existing tab', () => {
+  const evt = { preventDefault: jest.fn() };
+  const initialText = tabs(1);
+  const before = createWithText(initialText);
+  const after = handleTab(evt, before);
+
+  expect(toPlainText(before)).toEqual(initialText);
+  expect(toPlainText(after)).toEqual(initialText + tabs(1));
+})
+
+it('should replace existing content with the tab', () => {
+  const evt = { preventDefault: jest.fn() };
+  const initialText = "hello";
+
+  const currentContent = ContentState.createFromText(initialText);
+  const selectInitialtext = SelectionState.createEmpty(
+    currentContent.getBlockMap().first().getKey()
+  );
+  const before = EditorState.create({
+    allowUndo: true,
+    currentContent,
+    // Focus the entire initial word
+    selection: selectInitialtext.set('focusOffset', initialText.length),
+  });
+
+  const after = handleTab(evt, before);
+  expect(toPlainText(before)).toEqual(initialText);
+  expect(toPlainText(after)).toEqual(tabs(1));
+})