feat: export extra functions from the loader

src/csv-loader/loader.ts

@@ -20,6 +20,15 @@ export interface CsvLoaderOptions {
   writeToDisk?: boolean;
 }
 
+export interface CsvParseResult {
+  /** Parsed CSV data as array of objects */
+  data: Record<string, unknown>[];
+  /** Generated TypeScript type definition string (if emitTypes is true) */
+  typeDefinition?: string;
+  /** Property configurations for the CSV columns */
+  propertyConfigs: PropertyConfig[];
+}
+
 interface PropertyConfig {
   name: string;
   schema: any;
@@ -78,20 +87,25 @@ export default data;
 `;
 }
 
-export default function csvLoader(
-  this: LoaderContext<CsvLoaderOptions>,
-  content: string
-): string | Buffer {
-  const options = this.getOptions() as CsvLoaderOptions | undefined;
-  const delimiter = options?.delimiter ?? ',';
-  const quote = options?.quote ?? '"';
-  const escape = options?.escape ?? '\\';
-  const bom = options?.bom ?? true;
-  const comment = options?.comment === false ? undefined : (options?.comment ?? '#');
-  const trim = options?.trim ?? true;
-  const emitTypes = options?.emitTypes ?? true;
-  const typesOutputDir = options?.typesOutputDir ?? '';
-  const writeToDisk = options?.writeToDisk ?? false;
+/**
+ * Parse CSV content string into structured data with schema validation.
+ * This is a standalone function that doesn't depend on webpack/rspack LoaderContext.
+ * 
+ * @param content - CSV content string (must have at least headers + schema row + 1 data row)
+ * @param options - Parsing options
+ * @returns CsvParseResult containing parsed data and optional type definitions
+ */
+export function parseCsv(
+  content: string,
+  options: CsvLoaderOptions = {}
+): CsvParseResult {
+  const delimiter = options.delimiter ?? ',';
+  const quote = options.quote ?? '"';
+  const escape = options.escape ?? '\\';
+  const bom = options.bom ?? true;
+  const comment = options.comment === false ? undefined : (options.comment ?? '#');
+  const trim = options.trim ?? true;
+  const emitTypes = options.emitTypes ?? true;
 
   const records = parse(content, {
     delimiter,
@@ -152,10 +166,54 @@ export default function csvLoader(
     return obj;
   });
 
-  const json = JSON.stringify(objects, null, 2);
+  const result: CsvParseResult = {
+    data: objects,
+    propertyConfigs,
+  };
+
+  if (emitTypes) {
+    result.typeDefinition = generateTypeDefinition('', propertyConfigs);
+  }
+
+  return result;
+}
+
+/**
+ * Generate JavaScript module code from CSV content.
+ * Returns a string that can be used as a module export.
+ * 
+ * @param content - CSV content string
+ * @param options - Parsing options
+ * @returns JavaScript module code string
+ */
+export function csvToModule(
+  content: string,
+  options: CsvLoaderOptions = {}
+): { js: string; dts?: string } {
+  const result = parseCsv(content, options);
+  
+  const json = JSON.stringify(result.data, null, 2);
+  const js = `export default ${json};`;
+  
+  return {
+    js,
+    dts: result.typeDefinition,
+  };
+}
+
+export default function csvLoader(
+  this: LoaderContext<CsvLoaderOptions>,
+  content: string
+): string | Buffer {
+  const options = this.getOptions() as CsvLoaderOptions | undefined;
+  const emitTypes = options?.emitTypes ?? true;
+  const typesOutputDir = options?.typesOutputDir ?? '';
+  const writeToDisk = options?.writeToDisk ?? false;
+
+  const result = parseCsv(content, options);
 
   // Emit type definition file if enabled
-  if (emitTypes) {
+  if (emitTypes && result.typeDefinition) {
     const context = this.context || '';
     // Get relative path from context, normalize to forward slashes
     let relativePath = this.resourcePath.replace(context, '');
@@ -169,18 +227,17 @@ export default function csvLoader(
     const outputPath = typesOutputDir
       ? path.join(typesOutputDir, dtsFileName)
       : dtsFileName;
-    const dtsContent = generateTypeDefinition(this.resourcePath, propertyConfigs);
 
     if (writeToDisk) {
       // Write directly to disk (useful for dev server)
       const absolutePath = path.join(this.context || process.cwd(), typesOutputDir || '', dtsFileName);
       fs.mkdirSync(path.dirname(absolutePath), { recursive: true });
-      fs.writeFileSync(absolutePath, dtsContent);
+      fs.writeFileSync(absolutePath, result.typeDefinition);
     } else {
       // Emit to in-memory filesystem (for production build)
-      this.emitFile?.(outputPath, dtsContent);
+      this.emitFile?.(outputPath, result.typeDefinition);
     }
   }
 
-  return `export default ${json};`;
+  return `export default ${JSON.stringify(result.data, null, 2)};`;
 }