Merge pull request #4 from haensl/3

#3: Fix empty source transformation.

CHANGELOG.md

@@ -1,2 +1,6 @@
+## 1.0.1
+* [#3: Fix empty source transformation.](https://github.com/haensl/json-transform-stream/issues/3)
+* Update dependencies.
+
 ## 1.0.0
 * [#1: Bootstrap project.](https://github.com/haensl/json-transform-stream/issues/1)

index.js

@@ -12,6 +12,7 @@ module.exports = ({
     transform: (chunk, encoding, callback) => {
       if (first) {
         first = false;
+
         return callback(
           null,
           Buffer.concat([Buffer.from(pre), chunk])
@@ -23,13 +24,13 @@ module.exports = ({
         Buffer.concat([Buffer.from(separator), chunk])
       );
     },
-    final: function(callback) {
+    flush: function(callback) {
       if (first) {
         this.push(Buffer.from(pre));
-      } else {
-        this.push(Buffer.from(post));
       }
 
+      this.push(Buffer.from(post));
+
       process.nextTick(callback);
     }
   });

json-transform-stream.package.test.js

@@ -8,8 +8,8 @@ describe('json-transform-stream', () => {
     { index: 3 }
   ];
 
-  const iterator = function* () {
-    for (const d of data) {
+  const iterator = function* (_data = data) {
+    for (const d of _data) {
       yield JSON.stringify(d);
     }
   };
@@ -56,6 +56,30 @@ describe('json-transform-stream', () => {
           })
         );
     });
+
+    describe('empty source', () => {
+      beforeEach((done) => {
+        streamed = '';
+        const stream = Readable.from(iterator([]))
+          .pipe(JSONTransform({
+            pre: '{"data":[',
+            post: ']}'
+          }));
+        stream.on('data', (data) => {
+          streamed = `${streamed || ''}${data}`;
+        });
+        stream.on('end', done);
+      });
+
+      it('Allows to setup custom wrapping', () => {
+        expect(streamed)
+          .toEqual(
+            JSON.stringify({
+              data: []
+            })
+          );
+      });
+    });
   });
 
   describe('separator', () => {

json-transform-stream.test.js

@@ -8,8 +8,8 @@ describe('json-transform-stream', () => {
     { index: 3 }
   ];
 
-  const iterator = function* () {
-    for (const d of data) {
+  const iterator = function* (_data = data) {
+    for (const d of _data) {
       yield JSON.stringify(d);
     }
   };
@@ -56,6 +56,30 @@ describe('json-transform-stream', () => {
           })
         );
     });
+
+    describe('empty source', () => {
+      beforeEach((done) => {
+        streamed = '';
+        const stream = Readable.from(iterator([]))
+          .pipe(JSONTransform({
+            pre: '{"data":[',
+            post: ']}'
+          }));
+        stream.on('data', (data) => {
+          streamed = `${streamed || ''}${data}`;
+        });
+        stream.on('end', done);
+      });
+
+      it('Allows to setup custom wrapping', () => {
+        expect(streamed)
+          .toEqual(
+            JSON.stringify({
+              data: []
+            })
+          );
+      });
+    });
   });
 
   describe('separator', () => {