feat(tests): Add non-camelcase test for svelte-preprocess-css-modules

This commit introduces a new test case for the svelte-preprocess-css-modules
library. The test verifies that the library correctly handles CSS class names
that are not in camelcase. This is done by comparing the output of the
preprocessor with a snapshot file.

Author: ryoppippi

tests/non-camelcase/Input.svelte

@@ -0,0 +1,8 @@
+<script>
+	import s from '../assets/style.module.css';
+</script>
+
+<div class={s['success-message']}>
+	hello
+</div>
+

tests/non-camelcase/Output.svelte

@@ -0,0 +1,28 @@
+<script>
+	const s = {
+  error: "error_style-module-css-module-test",
+  "success-message": "success-message_style-module-css-module-test"
+};
+</script>
+
+<div class={s['success-message']}>
+	hello
+</div>
+
+
+<style>
+
+
+section {
+  padding: 10px;
+}
+
+.error_style-module-css-module-test {
+  color: red;
+}
+
+.success-message_style-module-css-module-test {
+  color: green;
+}
+
+</style>

tests/non-camelcase/non-camelcase.spec.ts

@@ -0,0 +1,22 @@
+import fs from 'node:fs/promises';
+import path from 'node:path';
+import { expect, it } from 'vitest';
+import { compiler } from '../compiler';
+
+export function resolve(file: string) {
+	return path.resolve(__dirname, file);
+}
+
+it('non-camelcase', { retry: 5 }, async () => {
+	const filename = resolve('Input.svelte');
+
+	const source = await fs.readFile(filename, 'utf-8');
+
+	const code = await compiler({
+		source,
+		preprocessOptions: { filename },
+		cssmodulesOptions: { convertToCamelCase: false },
+	});
+
+	await expect(code).toMatchFileSnapshot('./Output.svelte');
+});