Test case for #531

src/type.js

@@ -341,7 +341,7 @@ TypePrototype.encode = function encode(message, writer) {
  * @returns {Writer} writer
  */
 TypePrototype.encodeDelimited = function encodeDelimited(message, writer) {
-    return this.encode(message, writer && writer.fork() || writer).ldelim();
+    return this.encode(message, writer && writer.len ? writer.fork() : writer).ldelim();
 };
 
 /**

tests/data/simple.proto

@@ -0,0 +1,9 @@
+syntax = "proto2";
+
+message A {
+    required uint32 a = 1;
+}
+
+message B {
+    required string b = 1;
+}

tests/reuse.js

@@ -0,0 +1,53 @@
+var tape = require("tape");
+
+var protobuf = require("..");
+
+tape.test("reusing", function(test) {
+
+    var root = protobuf.loadSync("tests/data/simple.proto");
+
+    var A = root.lookup("A"),
+        B = root.lookup("B");
+
+    test.test("a writer should write", function(test) {
+
+        var writer = protobuf.Writer.create();
+
+        A.encodeDelimited({
+            a: 1
+        }, writer);
+
+        B.encodeDelimited({
+            b: 'a'
+        }, writer);
+
+        var buffer = writer.finish();
+
+        test.equal(buffer[0], 2, "length 2");
+        test.equal(buffer[1], 8, "id 1, wireType 0");
+        test.equal(buffer[2], 1, "number 1");
+        test.equal(buffer[3], 3, "length 3");
+        test.equal(buffer[4], 10, "id 1, wireType 2");
+        test.equal(buffer[5], 1, "length 1");
+        test.equal(buffer[6], 97, "string 'a'");
+
+        var reader = protobuf.Reader.create(buffer);
+
+        test.test("and a reader should", function(test) {
+
+            var a = A.decodeDelimited(reader);
+            test.deepEqual(a, { a: 1 }, "read back the first message");
+
+            var b = B.decodeDelimited(reader);
+            test.deepEqual(b, { b: 'a' }, "read back the second message");
+
+            test.equal(reader.pos, reader.len, "consume the reader");
+
+            test.end();
+        });
+
+        test.end();
+    });
+
+    test.end();
+});