Added support for absolute paths in annotations. You can also pass a …

…function in `options.preprocessor` to modify the contents of file before it is searched for dependencies.

README.md

@@ -70,3 +70,7 @@ Type: `Boolean`
 
 Whether to just continue instead of emitting an error if circular dependencies are detected (defaults to ```false```).
 
+#### options.preprocessor
+Type: `Function`
+
+This function allows to modify file contents before it is searched for dependencies.

index.js

@@ -38,8 +38,17 @@ function resolveDependencies(config) {
 
 			content = targetFile.contents.toString('utf8');
 
+			if (config.preprocessor) {
+				content = config.preprocessor(content);
+			}
+
 			while (match = pattern.exec(content)) {
-				filePath = path.join(path.dirname(targetFile.path), match[1]);
+				filePath = match[1];
+
+				// Augment file path if it's not absolute
+				if (filePath && filePath[0] !== '/') {
+					filePath = path.join(path.dirname(targetFile.path), filePath);
+				}
 
 				// Check for circular dependencies
 				try {

test/expected/main2.js

@@ -0,0 +1,6 @@
+console.log('test2.js');
+
+/**
+ * @requires test/test2.js
+ */
+console.log('main2.js');

test/fixtures/main2.js

@@ -0,0 +1,4 @@
+/**
+ * @requires test/test2.js
+ */
+console.log('main2.js');

test/fixtures/test/test2.js

@@ -0,0 +1 @@
+console.log('test2.js');

test/main.js

@@ -1,5 +1,6 @@
 var gulp = require('gulp'),
 	fs = require('fs'),
+	path = require('path'),
 	es = require('event-stream'),
 	assert = require('assert'),
 	concat = require('gulp-concat'),
@@ -24,6 +25,36 @@ describe('gulp-resolve-dependencies', function() {
 			}));
 	});
 
+	it('should use preprocessor and generate concatenated JS file', function(done) {
+		function toAbsolutePath(content) {
+			return content.replace(/\* @requires [\s-]*(.*\.js)/g, function(match, p1, offset, string) {
+				var absolutePath = '* @requires ' + path.join(__dirname, 'fixtures', p1);
+
+				return absolutePath;
+			});
+		}
+
+		gulp.src(__dirname + '/fixtures/main2.js')
+			.pipe(resolveDependencies({
+				preprocessor: toAbsolutePath
+			}))
+			.pipe(concat('main2.js'))
+			.pipe(gulp.dest(__dirname + '/results/'))
+			.pipe(es.wait(function() {
+				var expected = fs.readFileSync(__dirname + '/expected/main2.js', 'utf8');
+
+				assert.equal(
+					fs.readFileSync(__dirname + '/results/main2.js', 'utf8'),
+					expected
+				);
+
+				fs.unlinkSync(__dirname + '/results/main2.js');
+				fs.rmdirSync(__dirname + '/results/');
+
+				done();
+			}));
+	});
+
 	it('should throw error due to circular dependency', function(done) {
 		gulp.src(__dirname + '/circular/a.js')
 			.pipe(resolveDependencies())