test: jsToTreeNode basic and export injection

packages/integrations/mdx/test/mdx-util-js-to-tree-node.test.js

@@ -0,0 +1,53 @@
+import { jsToTreeNode } from '@astrojs/mdx/utils';
+import { compile } from '@mdx-js/mdx';
+import { expect } from 'chai';
+import { parse as parseESM } from 'es-module-lexer';
+import { rehypeReadingTime } from './test-utils.js'
+
+const sampleMdx = `# I'm MDX!`
+
+describe('jsToTreeNode', () => {
+	it('handles basic JS injection', async () => {
+		const js = `console.log('working')`
+		function injectConsoleLog() {
+			return function (tree) {
+				tree.children.unshift(
+					jsToTreeNode(js)
+				)
+			};
+		}
+
+		const compiled = await compile(sampleMdx, {
+			rehypePlugins: [injectConsoleLog],
+		})
+
+		expect(String(compiled.value)).to.contain(js)
+	})
+
+	it('handles export injection', async () => {
+		function injectExport() {
+			return function (tree) {
+				tree.children.unshift(
+					jsToTreeNode(`export const working = true`)
+				)
+			};
+		}
+
+		const compiled = await compile(sampleMdx, {
+			rehypePlugins: [injectExport],
+		})
+
+		const [, moduleExports] = parseESM(compiled.value)
+		expect(moduleExports).to.contain('working')
+	})
+
+	it('handles readingTime example', async () => {
+		const compiled = await compile(sampleMdx, {
+			rehypePlugins: [rehypeReadingTime],
+		})
+
+		const [, moduleExports] = parseESM(compiled.value)
+		expect(moduleExports).to.contain('readingTime')
+		expect(String(compiled.value)).to.match(/\d+ min read/)
+	})
+})