Stop using rootDir option

lib/Host.js

@@ -1,9 +1,10 @@
-var events = require('events');
-var fs     = require('fs');
-var log    = require('util').debuglog(require('../package').name);
-var os     = require('os');
-var path   = require('path');
-var util   = require('util');
+var commondir = require('commondir');
+var events    = require('events');
+var fs        = require('fs');
+var log       = require('util').debuglog(require('../package').name);
+var os        = require('os');
+var path      = require('path');
+var util      = require('util');
 
 module.exports = function (ts) {
 	function Host(currentDirectory, languageVersion) {
@@ -118,5 +119,17 @@ module.exports = function (ts) {
 		return ts.sys.readFile(normalized);
 	};
 
+	Host.prototype._rootDir = function () {
+		var dirs = [];
+		for (var filename in this.files) {
+			if (!Object.hasOwnProperty.call(this.files, filename)) continue;
+			if (filename === this._normalizedRelative(this.getDefaultLibFileName())) continue;
+
+			dirs.push(path.dirname(filename));
+		}
+		var result = commondir(this.currentDirectory, dirs);
+		return result;
+	};
+
 	return Host;
 };

lib/Tsifier.js

@@ -59,6 +59,7 @@ module.exports = function (ts) {
 				fileExists);
 		}
 
+		var files;
 		if (configFile) {
 			log('Using tsconfig file at ' + configFile);
 			var configFileContents = require(path.resolve(currentDirectory, configFile));
@@ -91,7 +92,7 @@ module.exports = function (ts) {
 		// The output directory needs to be distinct from the input directory to prevent the TS
 		// compiler from thinking that it might accidentally overwrite source files, which would
 		// prevent it from outputting e.g. the results of transpiling ES6 JS files with --allowJs.
-		parsed.options.rootDir = currentDirectory;
+		delete parsed.options.rootDir;
 		parsed.options.outDir = '__tsify__';
 
 		if (configFile) {
@@ -269,9 +270,13 @@ module.exports = function (ts) {
 	Tsifier.prototype.getCompiledFile = function (inputFile, alreadyMissedCache) {
 		var self = this;
 		var normalized = ts.normalizePath(inputFile);
+		var rootDir = self.host._rootDir();
 
 		var outputExtension = (self.opts.jsx === ts.JsxEmit.Preserve && isTsx(inputFile)) ? '.jsx' : '.js';
-		var outputFile = '__tsify__/' + replaceFileExtension(normalized, outputExtension);
+		var outputFile = '__tsify__/' + path.relative(
+			rootDir,
+			path.resolve(replaceFileExtension(normalized, outputExtension))
+		).replace(/\\/g, '/');
 		var output = self.host.output[outputFile];
 
 		if (!output) {

package.json

@@ -27,6 +27,7 @@
     "node": ">=0.12"
   },
   "dependencies": {
+    "commondir": "^1.0.1",
     "convert-source-map": "^1.1.0",
     "through2": "^2.0.0",
     "typescript": "~1.8.7"

test/test.js

@@ -568,7 +568,7 @@ function expectNoErrors(t, errors) {
 
 function expectErrors(t, actual, expected) {
 	t.equal(actual.length, expected.length, 'Should have the correct error count');
-	for (var i = 0; i < actual.length; ++i) {
+	for (var i = 0; i < actual.length && i < expected.length; ++i) {
 		t.equal(actual[i].fileName, expected[i].file, 'Error #' + i + ' should have filename ' + expected[i].name);
 		t.equal(actual[i].line, expected[i].line, 'Error #' + i + ' should be on line ' + expected[i].line);
 		t.equal(actual[i].column, expected[i].column, 'Error #' + i + ' should be on column ' + expected[i].column);