Move toolbar functions into redux reducer (#1763)

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

src/redux/note-details/generate-note-title.test.ts

@@ -0,0 +1,31 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { generateNoteTitle } from './generate-note-title'
+import { initialState } from './initial-state'
+
+describe('generate note title', () => {
+  it('will choose the frontmatter title first', () => {
+    const actual = generateNoteTitle(
+      { ...initialState.frontmatter, title: 'frontmatter', opengraph: { title: 'opengraph' } },
+      'first-heading'
+    )
+    expect(actual).toEqual('frontmatter')
+  })
+
+  it('will choose the opengraph title second', () => {
+    const actual = generateNoteTitle(
+      { ...initialState.frontmatter, opengraph: { title: 'opengraph' } },
+      'first-heading'
+    )
+    expect(actual).toEqual('opengraph')
+  })
+
+  it('will choose the first heading third', () => {
+    const actual = generateNoteTitle({ ...initialState.frontmatter }, 'first-heading')
+    expect(actual).toEqual('first-heading')
+  })
+})