fix: Move content into to frontend directory

Doing this BEFORE the merge prevents a lot of merge conflicts.

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

frontend/src/redux/note-details/frontmatter-extractor/extractor.test.ts

@@ -0,0 +1,94 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { extractFrontmatter } from './extractor'
+import type { PresentFrontmatterExtractionResult } from './types'
+
+describe('frontmatter extraction', () => {
+  describe('isPresent property', () => {
+    it('is false when note does not contain three dashes at all', () => {
+      const testNote = ['abcdef', 'more text']
+      const extraction = extractFrontmatter(testNote)
+      expect(extraction.isPresent).toBe(false)
+    })
+    it('is false when note does not start with three dashes', () => {
+      const testNote = ['', '---', 'this is not frontmatter']
+      const extraction = extractFrontmatter(testNote)
+      expect(extraction.isPresent).toBe(false)
+    })
+    it('is false when note start with less than three dashes', () => {
+      const testNote = ['--', 'this is not frontmatter']
+      const extraction = extractFrontmatter(testNote)
+      expect(extraction.isPresent).toBe(false)
+    })
+    it('is false when note starts with three dashes but contains other characters in the same line', () => {
+      const testNote = ['--- a', 'this is not frontmatter']
+      const extraction = extractFrontmatter(testNote)
+      expect(extraction.isPresent).toBe(false)
+    })
+    it('is false when note has no ending marker for frontmatter', () => {
+      const testNote = ['---', 'this is not frontmatter', 'because', 'there is no', 'end marker']
+      const extraction = extractFrontmatter(testNote)
+      expect(extraction.isPresent).toBe(false)
+    })
+    it('is false when note end marker is present but with not the same amount of dashes as start marker', () => {
+      const testNote = ['---', 'this is not frontmatter', '----', 'content']
+      const extraction = extractFrontmatter(testNote)
+      expect(extraction.isPresent).toBe(false)
+    })
+    it('is true when note end marker is present with the same amount of dashes as start marker', () => {
+      const testNote = ['---', 'this is frontmatter', '---', 'content']
+      const extraction = extractFrontmatter(testNote)
+      expect(extraction.isPresent).toBe(true)
+    })
+    it('is true when note end marker is present with the same amount of dashes as start marker but without content', () => {
+      const testNote = ['---', 'this is frontmatter', '---']
+      const extraction = extractFrontmatter(testNote)
+      expect(extraction.isPresent).toBe(true)
+    })
+    it('is true when note end marker is present with the same amount of dots as start marker', () => {
+      const testNote = ['---', 'this is frontmatter', '...', 'content']
+      const extraction = extractFrontmatter(testNote)
+      expect(extraction.isPresent).toBe(true)
+    })
+  })
+
+  describe('lineOffset property', () => {
+    it('is correct for single line frontmatter without content', () => {
+      const testNote = ['---', 'single line frontmatter', '...']
+      const extraction = extractFrontmatter(testNote) as PresentFrontmatterExtractionResult
+      expect(extraction.lineOffset).toEqual(3)
+    })
+    it('is correct for single line frontmatter with content', () => {
+      const testNote = ['---', 'single line frontmatter', '...', 'content']
+      const extraction = extractFrontmatter(testNote) as PresentFrontmatterExtractionResult
+      expect(extraction.lineOffset).toEqual(3)
+    })
+    it('is correct for multi-line frontmatter without content', () => {
+      const testNote = ['---', 'abc', '123', 'def', '...']
+      const extraction = extractFrontmatter(testNote) as PresentFrontmatterExtractionResult
+      expect(extraction.lineOffset).toEqual(5)
+    })
+    it('is correct for multi-line frontmatter with content', () => {
+      const testNote = ['---', 'abc', '123', 'def', '...', 'content']
+      const extraction = extractFrontmatter(testNote) as PresentFrontmatterExtractionResult
+      expect(extraction.lineOffset).toEqual(5)
+    })
+  })
+
+  describe('rawText property', () => {
+    it('contains single-line frontmatter text', () => {
+      const testNote = ['---', 'single-line', '...', 'content']
+      const extraction = extractFrontmatter(testNote) as PresentFrontmatterExtractionResult
+      expect(extraction.rawText).toEqual('single-line')
+    })
+    it('contains multi-line frontmatter text', () => {
+      const testNote = ['---', 'multi', 'line', '...', 'content']
+      const extraction = extractFrontmatter(testNote) as PresentFrontmatterExtractionResult
+      expect(extraction.rawText).toEqual('multi\nline')
+    })
+  })
+})