Allow specifying transforms via the compiler API

cli/asc.d.ts

@@ -5,6 +5,7 @@
 
 import { OptionDescription } from "./util/options";
 export { OptionDescription };
+import { Transform } from "./transform";
 
 /** Ready promise resolved once/if the compiler is ready. */
 export const ready: Promise<void>;
@@ -192,6 +193,8 @@ export interface APIOptions {
   listFiles?: (dirname: string, baseDir: string) => string[] | null;
   /** Handler for diagnostic messages. */
   reportDiagnostic?: DiagnosticReporter;
+  /** Additional transforms to apply. */
+  transforms?: Transform[];
 }
 
 /** Convenience function that parses and compiles source strings directly. */

cli/asc.js

@@ -501,6 +501,9 @@ exports.main = function main(argv, options, callback) {
 
   // Set up transforms
   const transforms = [];
+  if (Array.isArray(options.transforms)) {
+    transforms.push(...options.transforms);
+  }
   if (opts.transform) {
     let tsNodeRegistered = false;
     let transformArgs = unique(opts.transform);