feat: implement tree-sitter compatible markdown processor

Adds a special case implementation for markdown files that:
- Parses markdown headers and section line ranges
- Returns captures in a format compatible with tree-sitter
- Integrates with the existing parseFile function
- Includes comprehensive tests for the implementation

Signed-off-by: Eric Wheeler <[email protected]>

Author: Eric Wheeler

src/services/tree-sitter/__tests__/markdownIntegration.test.ts

@@ -0,0 +1,99 @@
+import { describe, expect, it, jest, beforeEach } from "@jest/globals"
+import * as fs from "fs/promises"
+import * as path from "path"
+import { parseSourceCodeDefinitionsForFile } from "../index"
+
+// Mock fs.readFile
+jest.mock("fs/promises", () => ({
+	readFile: jest.fn().mockImplementation(() => Promise.resolve("")),
+	stat: jest.fn().mockImplementation(() => Promise.resolve({ isDirectory: () => false })),
+}))
+
+// Mock fileExistsAtPath
+jest.mock("../../../utils/fs", () => ({
+	fileExistsAtPath: jest.fn().mockImplementation(() => Promise.resolve(true)),
+}))
+
+describe("Markdown Integration Tests", () => {
+	beforeEach(() => {
+		jest.clearAllMocks()
+	})
+
+	it("should parse markdown files and extract headers", async () => {
+		// Mock markdown content
+		const markdownContent =
+			"# Main Header\n\nThis is some content under the main header.\nIt spans multiple lines to meet the minimum section length.\n\n## Section 1\n\nThis is content for section 1.\nIt also spans multiple lines.\n\n### Subsection 1.1\n\nThis is a subsection with enough lines\nto meet the minimum section length requirement.\n\n## Section 2\n\nFinal section content.\nWith multiple lines.\n"
+
+		// Mock fs.readFile to return our markdown content
+		;(fs.readFile as jest.Mock).mockImplementation(() => Promise.resolve(markdownContent))
+
+		// Call the function with a markdown file path
+		const result = await parseSourceCodeDefinitionsForFile("test.md")
+
+		// Verify fs.readFile was called with the correct path
+		expect(fs.readFile).toHaveBeenCalledWith("test.md", "utf8")
+
+		// Check the result
+		expect(result).toBeDefined()
+		expect(result).toContain("# test.md")
+		expect(result).toContain("0--4 | # Main Header")
+		expect(result).toContain("5--9 | ## Section 1")
+		expect(result).toContain("10--14 | ### Subsection 1.1")
+		expect(result).toContain("15--19 | ## Section 2")
+	})
+
+	it("should handle markdown files with no headers", async () => {
+		// Mock markdown content with no headers
+		const markdownContent = "This is just some text.\nNo headers here.\nJust plain text."
+
+		// Mock fs.readFile to return our markdown content
+		;(fs.readFile as jest.Mock).mockImplementation(() => Promise.resolve(markdownContent))
+
+		// Call the function with a markdown file path
+		const result = await parseSourceCodeDefinitionsForFile("no-headers.md")
+
+		// Verify fs.readFile was called with the correct path
+		expect(fs.readFile).toHaveBeenCalledWith("no-headers.md", "utf8")
+
+		// Check the result
+		expect(result).toBeUndefined()
+	})
+
+	it("should handle markdown files with headers that don't meet minimum section length", async () => {
+		// Mock markdown content with headers but short sections
+		const markdownContent = "# Header 1\nShort section\n\n# Header 2\nAnother short section"
+
+		// Mock fs.readFile to return our markdown content
+		;(fs.readFile as jest.Mock).mockImplementation(() => Promise.resolve(markdownContent))
+
+		// Call the function with a markdown file path
+		const result = await parseSourceCodeDefinitionsForFile("short-sections.md")
+
+		// Verify fs.readFile was called with the correct path
+		expect(fs.readFile).toHaveBeenCalledWith("short-sections.md", "utf8")
+
+		// Check the result - should be undefined since no sections meet the minimum length
+		expect(result).toBeUndefined()
+	})
+
+	it("should handle markdown files with mixed header styles", async () => {
+		// Mock markdown content with mixed header styles
+		const markdownContent =
+			"# ATX Header\nThis is content under an ATX header.\nIt spans multiple lines to meet the minimum section length.\n\nSetext Header\n============\nThis is content under a setext header.\nIt also spans multiple lines to meet the minimum section length.\n"
+
+		// Mock fs.readFile to return our markdown content
+		;(fs.readFile as jest.Mock).mockImplementation(() => Promise.resolve(markdownContent))
+
+		// Call the function with a markdown file path
+		const result = await parseSourceCodeDefinitionsForFile("mixed-headers.md")
+
+		// Verify fs.readFile was called with the correct path
+		expect(fs.readFile).toHaveBeenCalledWith("mixed-headers.md", "utf8")
+
+		// Check the result
+		expect(result).toBeDefined()
+		expect(result).toContain("# mixed-headers.md")
+		expect(result).toContain("0--3 | # ATX Header")
+		expect(result).toContain("4--8 | Setext Header")
+	})
+})