Merge pull request #235 from jaredwray/feat-set-the-front-matter-on-a-source

feat: set the front matter on a source

Author: jaredwray

README.md

@@ -557,6 +557,7 @@ Ecto has added in some helper functions for frontmatter in markdown files. Front
 
 * `.hasFrontMatter(source: string): boolean` - This function checks if the markdown file has frontmatter. It takes in a string and returns a boolean value.
 * `.getFrontMatter(source: string): object` - This function gets the frontmatter from the markdown file. It takes in a string and returns an object.
+* `setFrontMatter(source:string, data: Record<string, unknown>)` - This function sets the front matter even if it already exists and returns the full source with the new front matter. 
 * `.removeFrontMatter(source: string): string` - This function removes the frontmatter from the markdown file. It takes in a string and returns a string.
 
 # How to Contribute

src/ecto.ts

@@ -432,6 +432,18 @@ export class Ecto {
 		return writr.frontMatter;
 	}
 
+	/**
+	 * Will set the front matter in the source and return the source
+	 * @param {string} source - The source to set the front matter
+	 * @param {Record<string, unknown>} data - The front matter data
+	 * @returns {string} - The source with the front matter
+	 */
+	public setFrontMatter(source: string, data: Record<string, unknown>): string {
+		const writr = new Writr(source);
+		writr.frontMatter = data;
+		return writr.content;
+	}
+
 	/**
 	 * Remove the Front Matter from the source
 	 * @param {string} source

test/frontmatter.test.ts

@@ -29,4 +29,38 @@ describe('Ecto FrontMatter', async () => {
 		const content = ecto.removeFrontMatter(frontMatterDocument);
 		expect(ecto.hasFrontMatter(content)).toBe(false);
 	});
+
+	test('should add front matter', async () => {
+		const ecto = new Ecto();
+		const frontMatter = {
+			title: 'Project Title',
+			date: '2023-10-01',
+			tags: ['project', 'documentation', 'example'],
+		};
+		const content = ecto.setFrontMatter(noFrontMatterDocument, frontMatter);
+		expect(ecto.hasFrontMatter(content)).toBe(true);
+	});
+
+	test('should add / update front matter with already existing', async () => {
+		const ecto = new Ecto();
+		const frontMatter = {
+			title: 'Project Title',
+			date: '2023-10-01',
+			tags: ['project', 'documentation', 'example'],
+		};
+		const content = ecto.setFrontMatter('', frontMatter);
+		expect(ecto.hasFrontMatter(content)).toBe(true);
+
+		const updatedFrontMatter = {
+			title: 'Updated Project Title',
+			date: '2023-10-02',
+			tags: ['project', 'documentation'],
+		};
+
+		const updatedContent = ecto.setFrontMatter(content, updatedFrontMatter);
+		const updatedFrontMatterContent = ecto.getFrontMatter(updatedContent);
+		expect(updatedFrontMatterContent?.title).toEqual('Updated Project Title');
+		expect(updatedFrontMatterContent?.date).toEqual('2023-10-02');
+		expect(updatedFrontMatterContent?.tags).toEqual(['project', 'documentation']);
+	});
 });