Stable coverage.

.gitignore

@@ -7,6 +7,7 @@
 node_modules/
 dist/
 
+
 # Compiled Java class files
 *.class
 
@@ -28,6 +29,7 @@ dist/
 
 # Unit test reports
 TEST*.xml
+coverage/
 
 # Generated by MacOS
 .DS_Store

src/ast-to-html.mjs

@@ -0,0 +1,7 @@
+import { toHtml } from 'hast-util-to-html';
+
+export function htmlToAst(ast) {
+	return toHtml(ast);
+}
+
+export default htmlToAst;

src/interpolate.mjs

@@ -28,7 +28,6 @@ function getMaskedData(node, ancestors) {
 function interpolateNode(node, ancestors) {
 	const data = getMaskedData(node, ancestors);
 
-	// Interpolate properties
 	if (node.properties && typeof node.properties === 'object') {
 		for (const key in node.properties) {
 			if (typeof node.properties[key] === 'string') {
@@ -44,7 +43,6 @@ function interpolateNode(node, ancestors) {
 		}
 	}
 
-	// Interpolate text content for text nodes
 	if (node.type === 'text' && node.value) {
 		node.value = interpolateString(node.value, data.interp);
 	}
@@ -54,9 +52,14 @@ function interpolateNode(node, ancestors) {
 
 function interpolateString(str, data) {
 	const context = createContext({ ...data, ...global });
-	const interpolatedStr = runInContext(`\`${str}\``, context);
 
-	return interpolatedStr;
+	try {
+		const interpolatedStr = runInContext(`\`${str}\``, context);
+		return interpolatedStr;
+	} catch (e) {
+		console.error('Error interpolating string:', e);
+		return str;
+	}
 }
 
 export default interpolate;

src/util.mjs

@@ -1 +1,20 @@
+export function cloneNode (node) {
+	return JSON.parse(JSON.stringify(node));
+}
 
+export function createAstNode (type, props, children) {
+	const ast = {
+		type: type,
+		props: props,
+		children: children || [],
+	};
+	return ast;
+}
+
+// Test if the node is an object with a "type" value (including undefined)
+export function isAstNode (node) {
+	return (typeof node === 'object')
+		&& (node !== null)
+		&& ('type' in node)
+	;
+}

test/interpolate.test.mjs

@@ -8,8 +8,7 @@ describe("interpolate()", () => {
 		expect(interpolate).toBeDefined();
 	})
 
-	it("should interpolate", () => {
+	it("should interpolate a single node", () => {
-
 		const uninterpolated = '<div class="${classname}"></div>';
 		const expected       = '<div class="foo"></div>';
 
@@ -21,4 +20,69 @@ describe("interpolate()", () => {
 		expect(rendered).toEqual(expected);
 	})
 
+	it("should interpolate a nested tree", () => {
+		const uninterpolated = `
+			<div class="\${classname}">
+				<p>This is a \${data.stringInPTag} in a p tag</p>
+				<p id="\${data.id}">This is a p with an interpolated id</p>
+				<ul class="\${data.listClass}">
+					<li>\${data.listItem}</li>
+				</ul>
+			</div>
+		`;
+		const expected = `
+			<div class="foo">
+				<p>This is a string in a p tag</p>
+				<p id="foo">This is a p with an interpolated id</p>
+				<ul class="bar">
+					<li>baz</li>
+				</ul>
+			</div>
+		`;
+
+		const data = {
+			classname: "foo",
+			data: {
+				stringInPTag: "string",
+				id: "foo",
+				listClass: "bar",
+				listItem: "baz",
+			},
+		};
+		const ast            = htmlToAst(uninterpolated);
+		const interpolated   = interpolate(ast, data);
+		const rendered       = astToHtml(interpolated);
+
+		expect(rendered).toEqual(expected);
+	})
+
+	it("should handle arbitrary javascript", () => {
+		const uninterpolated = `
+			<div class="\${classname}">
+				<p>simple: 3 * 12 = \${3 * 12}</p>
+				<p>named function: 3^2 = \${square(3)}</p>
+				<p>arrow function: 5*2 = \${(num => (num * 2))(5)}</p>
+				<p>arrow function: 3-8 = \${(num => (num - 8))(3)}</p>
+			</div>
+		`;
+		const expected = `
+			<div class="foo">
+				<p>simple: 3 * 12 = 36</p>
+				<p>named function: 3^2 = 9</p>
+				<p>arrow function: 5*2 = 10</p>
+				<p>arrow function: 3-8 = -5</p>
+			</div>
+		`;
+
+		const data = {
+			classname: "foo",
+			square: (num) => Math.pow(num, 2),
+		};
+		const ast            = htmlToAst(uninterpolated);
+		const interpolated   = interpolate(ast, data);
+		const rendered       = astToHtml(interpolated);
+
+		expect(rendered).toEqual(expected);
+	})
+
 });

test/util.test.mjs

@@ -84,7 +84,5 @@ describe("isAstNode()", () => {
 		});
 	});
 
-
-
 });