diff --git a/src/datalayout.js b/src/datalayout.js
index 329dd0fd0..e32dd91e5 100644
--- a/src/datalayout.js
+++ b/src/datalayout.js
@@ -6,6 +6,7 @@ const assert = require('assert'),
 class DataLayout {
     constructor(localRoot, dirMap) {
         assert.strictEqual(typeof localRoot, 'string');
+        assert(path.isAbsolute(localRoot));
         assert(Array.isArray(dirMap), 'Expecting layout to be an array');
 
         this._localRoot = localRoot;
@@ -13,6 +14,7 @@ class DataLayout {
         this._remoteRegexps = dirMap.map((l) => new RegExp('^\\./' + l.remoteDir + '/?'));
         this._localRegexps = dirMap.map((l) => new RegExp('^' + l.localDir + '/?'));
     }
+    // returns absolute path
     toLocalPath(remoteName) {
         assert.strictEqual(typeof remoteName, 'string');
 
diff --git a/src/test/datalayout-test.js b/src/test/datalayout-test.js
new file mode 100644
index 000000000..96f9f23da
--- /dev/null
+++ b/src/test/datalayout-test.js
@@ -0,0 +1,87 @@
+'use strict';
+
+/* global it:false */
+/* global describe:false */
+/* global before:false */
+
+'use strict';
+
+const DataLayout = require('../datalayout.js'),
+    expect = require('expect.js');
+
+describe('DataLayout', function () {
+    describe('no dirMap', function () {
+        const BOX_DATA_DIR = '/home/yellowtent/boxdata/box';
+        const dataLayout = new DataLayout(BOX_DATA_DIR, []);
+
+        it('localRoot', function () {
+            expect(dataLayout.localRoot()).to.be(BOX_DATA_DIR);
+        });
+
+        it('getBasename', function () {
+            expect(dataLayout.getBasename()).to.be('box');
+        });
+
+        it('localPaths', function () {
+            expect(dataLayout.localPaths()).to.eql([ BOX_DATA_DIR ]);
+        });
+
+        it('toLocalPath', function () {
+            expect(dataLayout.toLocalPath('./s1')).to.be(`${BOX_DATA_DIR}/s1`);
+            expect(dataLayout.toLocalPath('./s1/')).to.be(`${BOX_DATA_DIR}/s1/`);
+            expect(dataLayout.toLocalPath('./s1/s2')).to.be(`${BOX_DATA_DIR}/s1/s2`);
+        });
+
+        it('toRemotePath', function () {
+            expect(dataLayout.toRemotePath(`${BOX_DATA_DIR}`)).to.be('./');
+            expect(dataLayout.toRemotePath(`${BOX_DATA_DIR}/s1`)).to.be('./s1');
+            expect(dataLayout.toRemotePath(`${BOX_DATA_DIR}/s1/`)).to.be('./s1/');
+            expect(dataLayout.toRemotePath(`${BOX_DATA_DIR}/s1/s2`)).to.be('./s1/s2');
+        });
+    });
+
+    describe('with dirMap', function () {
+        const APP_DATA_DIR = '/home/yellowtent/appsdata/appid';
+        const EXT_DIR = '/srv/hsb';
+        const dataLayout = new DataLayout(APP_DATA_DIR, [ { localDir: EXT_DIR, remoteDir: 'data' }]);
+
+        it('localRoot', function () {
+            expect(dataLayout.localRoot()).to.be(APP_DATA_DIR);
+        });
+
+        it('getBasename', function () {
+            expect(dataLayout.getBasename()).to.be('appid');
+        });
+
+        it('localPaths', function () {
+            expect(dataLayout.localPaths()).to.eql([ APP_DATA_DIR, '/srv/hsb' ]);
+        });
+
+        it('toLocalPath - root', function () {
+            expect(dataLayout.toLocalPath('./s1')).to.be(`${APP_DATA_DIR}/s1`);
+            expect(dataLayout.toLocalPath('./s1/')).to.be(`${APP_DATA_DIR}/s1/`);
+            expect(dataLayout.toLocalPath('./s1/s2')).to.be(`${APP_DATA_DIR}/s1/s2`);
+        });
+
+        it('toLocalPath - extdir', function () {
+            expect(dataLayout.toLocalPath('./data/s1')).to.be(`${EXT_DIR}/s1`);
+            expect(dataLayout.toLocalPath('./data/s1/')).to.be(`${EXT_DIR}/s1/`);
+            expect(dataLayout.toLocalPath('./data/s1/s2')).to.be(`${EXT_DIR}/s1/s2`);
+        });
+
+        it('toRemotePath - root', function () {
+            expect(dataLayout.toRemotePath(`${APP_DATA_DIR}`)).to.be('./');
+            expect(dataLayout.toRemotePath(`${APP_DATA_DIR}/s1`)).to.be('./s1');
+            expect(dataLayout.toRemotePath(`${APP_DATA_DIR}/s1/`)).to.be('./s1/');
+            expect(dataLayout.toRemotePath(`${APP_DATA_DIR}/s1/s2`)).to.be('./s1/s2');
+        });
+
+        it('toRemotePath - extdir', function () {
+            expect(dataLayout.toRemotePath(`${EXT_DIR}`)).to.be('./data/');
+            expect(dataLayout.toRemotePath(`${EXT_DIR}/s1`)).to.be('./data/s1');
+            expect(dataLayout.toRemotePath(`${EXT_DIR}/s1/`)).to.be('./data/s1/');
+            expect(dataLayout.toRemotePath(`${EXT_DIR}/s1/s2`)).to.be('./data/s1/s2');
+        });
+    });
+
+});
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