Add the Transformer interface

Author: Cédric Belin

lib/fast_transformer.d.ts

@@ -1,7 +1,9 @@
+import {Transformer} from "./transformer.js";
+
 /**
  * Removes comments and whitespace from a PHP script, by calling a Web service.
  */
-export class FastTransformer {
+export class FastTransformer implements Transformer {
 
 	/**
 	 * Creates a new fast transformer.

lib/index.d.ts

@@ -3,6 +3,7 @@ import {GulpPlugin, GulpPluginOptions} from "./gulp_plugin.js";
 export * from "./fast_transformer.js";
 export * from "./gulp_plugin.js";
 export * from "./safe_transformer.js";
+export * from "./transformer.js";
 
 /**
  * Creates a new Gulp plugin.

lib/safe_transformer.d.ts

@@ -1,7 +1,9 @@
+import {Transformer} from "./transformer.js";
+
 /**
  * Removes comments and whitespace from a PHP script, by calling a PHP process.
  */
-export class SafeTransformer {
+export class SafeTransformer implements Transformer {
 
 	/**
 	 * Creates a new safe transformer.

lib/transformer.d.ts

@@ -0,0 +1,18 @@
+/**
+ * Removes comments and whitespace from a PHP script.
+ */
+export interface Transformer {
+
+	/**
+	 * Closes this transformer and releases any resources associated with it.
+	 * @returns Resolves when the transformer is finally disposed.
+	 */
+	close(): Promise<void>;
+
+	/**
+	 * Processes a PHP script.
+	 * @param file The path to the PHP script.
+	 * @returns The transformed script.
+	 */
+	transform(file: string): Promise<string>;
+}