feat: esbuild csv-loader support

src/csv-loader/esbuild.ts

@@ -0,0 +1,118 @@
+import type { CsvLoaderOptions } from './loader.js';
+import { csvToModule } from './loader.js';
+import * as path from 'path';
+import * as fs from 'fs';
+import type { Plugin, OnLoadArgs, OnLoadResult } from 'esbuild';
+
+export interface CsvEsbuildOptions extends CsvLoaderOptions {
+  /** Include pattern for CSV files (default: /\.csv$/) */
+  include?: RegExp | string | Array<RegExp | string>;
+  /** Exclude pattern for CSV files */
+  exclude?: RegExp | string | Array<RegExp | string>;
+}
+
+function matchesFilter(
+  path: string,
+  filter: RegExp | undefined
+): boolean {
+  if (!filter) return true;
+  return filter.test(path);
+}
+
+/**
+ * Esbuild plugin for loading CSV files with inline-schema validation.
+ */
+export function csvLoader(options: CsvEsbuildOptions = {}): Plugin {
+  const {
+    include = /\.csv$/,
+    exclude,
+    emitTypes = true,
+    typesOutputDir = '',
+    writeToDisk = false,
+    ...parseOptions
+  } = options;
+
+  // Convert include/exclude to RegExp for esbuild filter
+  const includeFilter = includeToRegExp(include);
+  const excludeFilter = exclude ? includeToRegExp(exclude) : undefined;
+
+  return {
+    name: 'inline-schema-csv',
+
+    setup(build) {
+      build.onLoad({ filter: includeFilter }, async (args: OnLoadArgs) => {
+        // Check exclude pattern
+        if (excludeFilter && !matchesFilter(args.path, excludeFilter)) {
+          return null;
+        }
+
+        // Only process .csv files
+        if (!args.path.endsWith('.csv')) {
+          return null;
+        }
+
+        // Read the file content
+        let content: string;
+        try {
+          content = await fs.promises.readFile(args.path, 'utf-8');
+        } catch (error) {
+          return {
+            errors: [{ text: `Failed to read file: ${args.path}` }],
+          };
+        }
+
+        // Infer resource name from filename
+        const fileName = path.basename(args.path, '.csv').split('.')[0];
+        const resourceName = fileName
+          .replace(/[-_\s]+(.)?/g, (_, char) => char ? char.toUpperCase() : '')
+          .replace(/^(.)/, (_, char) => char.toUpperCase());
+
+        const result = csvToModule(content, {
+          ...parseOptions,
+          emitTypes,
+          resourceName,
+        });
+
+        // Emit type definition file if enabled
+        if (emitTypes && result.dts) {
+          const dtsPath = typesOutputDir
+            ? path.join(typesOutputDir, path.basename(args.path) + '.d.ts')
+            : args.path + '.d.ts';
+
+          if (writeToDisk) {
+            // Write directly to disk
+            const absolutePath = path.isAbsolute(dtsPath)
+              ? dtsPath
+              : path.join(process.cwd(), dtsPath);
+            fs.mkdirSync(path.dirname(absolutePath), { recursive: true });
+            fs.writeFileSync(absolutePath, result.dts);
+          }
+          // Note: esbuild doesn't have a direct emitFile API like Rollup
+          // For type generation with writeToDisk: false, you'd need to 
+          // use a separate type generation step or plugin
+        }
+
+        const onLoadResult: OnLoadResult = {
+          contents: result.js,
+          loader: 'js',
+        };
+
+        return onLoadResult;
+      });
+    },
+  };
+}
+
+function includeToRegExp(include: RegExp | string | Array<RegExp | string>): RegExp {
+  if (include instanceof RegExp) {
+    return include;
+  }
+  if (Array.isArray(include)) {
+    // Use the first pattern or create a combined pattern
+    const first = include[0];
+    return first instanceof RegExp ? first : new RegExp(first);
+  }
+  return new RegExp(include);
+}
+
+export default csvLoader;