add tests for custom date separator

test/src/helpers/index_timestamp.js

@@ -5,15 +5,15 @@ import indexTimestamp from '../../../lib/helpers/index_timestamp';
 
 const anchor = '2016-04-02T01:02:03.456'; // saturday
 
-describe('Index interval', function () {
-  describe('indexTimestamp construction', function () {
+describe('Index timestamp interval', function () {
+  describe('construction', function () {
     it('should throw given an invalid interval', function () {
       const init = () => indexTimestamp('bananas');
       expect(init).to.throwException(/invalid.+interval/i);
     });
   });
 
-  describe('indexTimestamp timestamps', function () {
+  describe('timestamps', function () {
     let clock;
 
     beforeEach(function () {
@@ -24,6 +24,7 @@ describe('Index interval', function () {
       clock.restore();
     });
 
+    describe('formats', function () {
       it('should return the year', function () {
         const timestamp = indexTimestamp('year');
         expect(timestamp).to.equal('2016');
@@ -54,4 +55,22 @@ describe('Index interval', function () {
         expect(timestamp).to.equal('2016-04-02-01-02');
       });
     });
+
+    describe('date separator', function () {
+      it('should be customizable', function () {
+        const separators = ['-', '.', '_'];
+        separators.forEach(separator => {
+          const str = `2016${separator}04${separator}02${separator}01${separator}02`;
+          const timestamp = indexTimestamp('minute', separator);
+          expect(timestamp).to.equal(str);
+        });
+      });
+
+      it('should throw if a letter is used', function () {
+        const separator = 'a';
+        const fn = () => indexTimestamp('minute', separator);
+        expect(fn).to.throwException();
+      });
+    });
+  });
 });