THRIFT-4573 Support binary fields in union counts

This commit also fixes another, related issue: Since union support was
added in b3654df, `Count*` methods (and count checks in `Write`
methods) were only generated if there was at least 1 pointer field.

But pointer fields are not the only nullable types in Go, slices and
maps can also be set the nil, which are now taken into account.

Client: go

compiler/cpp/src/thrift/generate/t_go_generator.cc

@@ -1387,6 +1387,14 @@ void t_go_generator::generate_go_struct_definition(ostream& out,
       }
       out << endl;
     }
+
+    // num_setable is used for deciding if Count* methods will be generated for union fields.
+    // This applies to all nullable fields including slices (used for set, list and binary) and maps, not just pointers.
+    t_type* type = fieldType->get_true_type();
+    if (is_pointer_field(*m_iter)|| type->is_map() || type->is_set() || type->is_list() || type->is_binary()) {
+      num_setable += 1;
+    }
+
     if (is_pointer_field(*m_iter)) {
       string goOptType = type_to_go_type_with_opt(fieldType, true);
       string maybepointer = goOptType != goType ? "*" : "";
@@ -1397,7 +1405,6 @@ void t_go_generator::generate_go_struct_definition(ostream& out,
       out << indent() << "  }" << endl;
       out << indent() << "return " << maybepointer << "p." << publicized_name << endl;
       out << indent() << "}" << endl;
-      num_setable += 1;
     } else {
       out << endl;
       out << indent() << "func (p *" << tstruct_name << ") Get" << publicized_name << "() "
@@ -1491,7 +1498,7 @@ void t_go_generator::generate_countsetfields_helper(ostream& out,
 
     t_type* type = (*f_iter)->get_type()->get_true_type();
 
-    if (!(is_pointer_field(*f_iter) || type->is_map() || type->is_set() || type->is_list()))
+    if (!(is_pointer_field(*f_iter) || type->is_map() || type->is_set() || type->is_list() || type->is_binary()))
       continue;
 
     const string field_name(publicize(escape_string((*f_iter)->get_name())));

lib/go/test/Makefile.am

@@ -32,6 +32,7 @@ gopath: $(THRIFT) $(THRIFTTEST) \
 				TypedefFieldTest.thrift \
 				RefAnnotationFieldsTest.thrift \
 				UnionDefaultValueTest.thrift \
+				UnionBinaryTest.thrift \
 				ErrorTest.thrift \
 				NamesTest.thrift \
 				InitialismsTest.thrift \
@@ -50,6 +51,7 @@ gopath: $(THRIFT) $(THRIFTTEST) \
 	$(THRIFT) $(THRIFTARGS) TypedefFieldTest.thrift
 	$(THRIFT) $(THRIFTARGS) RefAnnotationFieldsTest.thrift
 	$(THRIFT) $(THRIFTARGS) UnionDefaultValueTest.thrift
+	$(THRIFT) $(THRIFTARGS) UnionBinaryTest.thrift
 	$(THRIFT) $(THRIFTARGS) ErrorTest.thrift
 	$(THRIFT) $(THRIFTARGS) NamesTest.thrift
 	$(THRIFT) $(THRIFTARGS) InitialismsTest.thrift
@@ -74,7 +76,8 @@ check: gopath
 				namestest \
 				initialismstest \
 				dontexportrwtest \
-				ignoreinitialismstest
+				ignoreinitialismstest \
+				unionbinarytest
 	GOPATH=`pwd`/gopath $(GO) test thrift tests dontexportrwtest
 
 clean-local:
@@ -95,6 +98,7 @@ EXTRA_DIST = \
 	OptionalFieldsTest.thrift \
 	RefAnnotationFieldsTest.thrift \
 	UnionDefaultValueTest.thrift \
+	UnionBinaryTest.thrift \
 	ServicesTest.thrift \
 	TypedefFieldTest.thrift \
 	ErrorTest.thrift \

lib/go/test/UnionBinaryTest.thrift

@@ -0,0 +1,25 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+# See https://issues.apache.org/jira/browse/THRIFT-4573
+union Sample {
+  1: map<string, string> u1,
+  2: binary u2,
+  3: list<string> u3
+}

lib/go/test/tests/union_binary_test.go

@@ -0,0 +1,36 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package tests
+
+import (
+	"testing"
+	"unionbinarytest"
+)
+
+
+// See https://issues.apache.org/jira/browse/THRIFT-4573
+func TestUnionBinary(t *testing.T) {
+	s := unionbinarytest.NewSample()
+	s.U1 = map[string]string{}
+	s.U2 = []byte{}
+	if n := s.CountSetFieldsSample(); n != 2 {
+		t.Errorf("Expected 2 set fields, got %d!", n)
+	}
+}