feat: add unit tests for prompt templates

src/lib/utils/index.test.ts

@@ -0,0 +1,66 @@
+import { promptTemplate } from '$lib/utils/index';
+import { expect, test } from 'vitest';
+
+test('promptTemplate correctly replaces {{prompt}} placeholder', () => {
+	const template = 'Hello {{prompt}}!';
+	const prompt = 'world';
+	const expected = 'Hello world!';
+	const actual = promptTemplate(template, prompt);
+	expect(actual).toBe(expected);
+});
+
+test('promptTemplate correctly replaces {{prompt:start:<length>}} placeholder', () => {
+	const template = 'Hello {{prompt:start:3}}!';
+	const prompt = 'world';
+	const expected = 'Hello wor!';
+	const actual = promptTemplate(template, prompt);
+	expect(actual).toBe(expected);
+});
+
+test('promptTemplate correctly replaces {{prompt:end:<length>}} placeholder', () => {
+	const template = 'Hello {{prompt:end:3}}!';
+	const prompt = 'world';
+	const expected = 'Hello rld!';
+	const actual = promptTemplate(template, prompt);
+	expect(actual).toBe(expected);
+});
+
+test('promptTemplate correctly replaces {{prompt:middletruncate:<length>}} placeholder when prompt length is greater than length', () => {
+	const template = 'Hello {{prompt:middletruncate:4}}!';
+	const prompt = 'world';
+	const expected = 'Hello wo...ld!';
+	const actual = promptTemplate(template, prompt);
+	expect(actual).toBe(expected);
+});
+
+test('promptTemplate correctly replaces {{prompt:middletruncate:<length>}} placeholder when prompt length is less than or equal to length', () => {
+	const template = 'Hello {{prompt:middletruncate:5}}!';
+	const prompt = 'world';
+	const expected = 'Hello world!';
+	const actual = promptTemplate(template, prompt);
+	expect(actual).toBe(expected);
+});
+
+test('promptTemplate returns original template when no placeholders are present', () => {
+	const template = 'Hello world!';
+	const prompt = 'world';
+	const expected = 'Hello world!';
+	const actual = promptTemplate(template, prompt);
+	expect(actual).toBe(expected);
+});
+
+test('promptTemplate does not replace placeholders inside of replaced placeholders', () => {
+	const template = 'Hello {{prompt}}!';
+	const prompt = 'World, {{prompt}} injection';
+	const expected = 'Hello World, {{prompt}} injection!';
+	const actual = promptTemplate(template, prompt);
+	expect(actual).toBe(expected);
+});
+
+test('promptTemplate correctly replaces multiple placeholders', () => {
+	const template = 'Hello {{prompt}}! This is {{prompt:start:3}}!';
+	const prompt = 'world';
+	const expected = 'Hello world! This is wor!';
+	const actual = promptTemplate(template, prompt);
+	expect(actual).toBe(expected);
+});