Fix go generator undefined Package name, also throwing exception (#7632)

* Fix go generator undefined Package, also throw exception in specific examples.

* Add test for go generator import problem

* Add new version of generated go file. Fix conflict.

* Add executable permission to generate_code.py script.

* Improve test quality, remove unwanted generated files, better naming

* Fix comments

* clang format

Co-authored-by: Derek Bailey <derekbailey@google.com>

6 files changed, 218 insertions, 12 deletions

diff --git a/tests/GoTest.sh b/tests/GoTest.sh
index 85253c17..8e73af24 100755
--- a/tests/GoTest.sh
+++ b/tests/GoTest.sh
@@ -20,26 +20,18 @@ go_path=${test_dir}/go_gen
 go_src=${go_path}/src
 
 # Emit Go code for the example schemas in the test dir:
-../flatc -g --gen-object-api -I include_test monster_test.fbs optional_scalars.fbs
+../flatc -g --gen-object-api -I include_test -o ${go_src} monster_test.fbs optional_scalars.fbs
+../flatc -g --gen-object-api -I include_test/sub -o ${go_src} include_test/order.fbs
+../flatc -g --gen-object-api -o ${go_src}/Pizza include_test/sub/no_namespace.fbs
 
 # Go requires a particular layout of files in order to link multiple packages.
 # Copy flatbuffer Go files to their own package directories to compile the
 # test binary:
-mkdir -p ${go_src}/MyGame/Example
-mkdir -p ${go_src}/MyGame/Example2
 mkdir -p ${go_src}/github.com/google/flatbuffers/go
 mkdir -p ${go_src}/flatbuffers_test
-mkdir -p ${go_src}/optional_scalars
 
-cp -a MyGame/*.go ./go_gen/src/MyGame/
-cp -a MyGame/Example/*.go ./go_gen/src/MyGame/Example/
-cp -a MyGame/Example2/*.go ./go_gen/src/MyGame/Example2/
-# do not compile the gRPC generated files, which are not tested by go_test.go
-# below, but have their own test.
-rm ./go_gen/src/MyGame/Example/*_grpc.go
 cp -a ../go/* ./go_gen/src/github.com/google/flatbuffers/go
 cp -a ./go_test.go ./go_gen/src/flatbuffers_test/
-cp -a optional_scalars/*.go ./go_gen/src/optional_scalars
 
 # https://stackoverflow.com/a/63545857/7024978
 # We need to turn off go modules for this script
@@ -72,7 +64,7 @@ else
     exit 1
 fi
 
-NOT_FMT_FILES=$(gofmt -l MyGame)
+NOT_FMT_FILES=$(gofmt -l .)
 if [[ ${NOT_FMT_FILES} != "" ]]; then
     echo "These files are not well gofmt'ed:"
     echo
diff --git a/tests/Pizza.go b/tests/Pizza.go
new file mode 100644
index 00000000..08df9e16
--- /dev/null
+++ b/tests/Pizza.go
@@ -0,0 +1,78 @@
+// Code generated by the FlatBuffers compiler. DO NOT EDIT.
+
+package Pizza
+
+import (
+	flatbuffers "github.com/google/flatbuffers/go"
+)
+
+type PizzaT struct {
+	Size int32 `json:"size"`
+}
+
+func (t *PizzaT) Pack(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
+	if t == nil { return 0 }
+	PizzaStart(builder)
+	PizzaAddSize(builder, t.Size)
+	return PizzaEnd(builder)
+}
+
+func (rcv *Pizza) UnPackTo(t *PizzaT) {
+	t.Size = rcv.Size()
+}
+
+func (rcv *Pizza) UnPack() *PizzaT {
+	if rcv == nil { return nil }
+	t := &PizzaT{}
+	rcv.UnPackTo(t)
+	return t
+}
+
+type Pizza struct {
+	_tab flatbuffers.Table
+}
+
+func GetRootAsPizza(buf []byte, offset flatbuffers.UOffsetT) *Pizza {
+	n := flatbuffers.GetUOffsetT(buf[offset:])
+	x := &Pizza{}
+	x.Init(buf, n+offset)
+	return x
+}
+
+func GetSizePrefixedRootAsPizza(buf []byte, offset flatbuffers.UOffsetT) *Pizza {
+	n := flatbuffers.GetUOffsetT(buf[offset+flatbuffers.SizeUint32:])
+	x := &Pizza{}
+	x.Init(buf, n+offset+flatbuffers.SizeUint32)
+	return x
+}
+
+func (rcv *Pizza) Init(buf []byte, i flatbuffers.UOffsetT) {
+	rcv._tab.Bytes = buf
+	rcv._tab.Pos = i
+}
+
+func (rcv *Pizza) Table() flatbuffers.Table {
+	return rcv._tab
+}
+
+func (rcv *Pizza) Size() int32 {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(4))
+	if o != 0 {
+		return rcv._tab.GetInt32(o + rcv._tab.Pos)
+	}
+	return 0
+}
+
+func (rcv *Pizza) MutateSize(n int32) bool {
+	return rcv._tab.MutateInt32Slot(4, n)
+}
+
+func PizzaStart(builder *flatbuffers.Builder) {
+	builder.StartObject(1)
+}
+func PizzaAddSize(builder *flatbuffers.Builder, size int32) {
+	builder.PrependInt32Slot(0, size, 0)
+}
+func PizzaEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
+	return builder.EndObject()
+}
diff --git a/tests/go_test.go b/tests/go_test.go
index a04ef2c9..d454b564 100644
--- a/tests/go_test.go
+++ b/tests/go_test.go
@@ -17,6 +17,8 @@
 package main
 
 import (
+	order "order"
+	pizza "Pizza"
 	mygame "MyGame"          // refers to generated code
 	example "MyGame/Example" // refers to generated code
 	"encoding/json"
@@ -98,6 +100,24 @@ func TestTextParsing(t *testing.T) {
 	}
 }
 
+func CheckNoNamespaceImport(fail func(string, ...interface{})) {
+	const size = 13
+	// Order a pizza with specific size
+	builder := flatbuffers.NewBuilder(0)
+	ordered_pizza := pizza.PizzaT{Size: size}
+	food := order.FoodT{Pizza: &ordered_pizza}
+	builder.Finish(food.Pack(builder))
+
+	// Receive order
+	received_food := order.GetRootAsFood(builder.FinishedBytes(), 0)
+	received_pizza := received_food.Pizza(nil).UnPack()
+
+	// Check if received pizza is equal to ordered pizza
+	if !reflect.DeepEqual(ordered_pizza, *received_pizza) {
+		fail(FailString("no namespace import", ordered_pizza, received_pizza))
+	}
+}
+
 // TestAll runs all checks, failing if any errors occur.
 func TestAll(t *testing.T) {
 	// Verify that the Go FlatBuffers runtime library generates the
@@ -160,6 +180,9 @@ func TestAll(t *testing.T) {
 	// Check a parent namespace import
 	CheckParentNamespace(t.Fatalf)
 
+	// Check a no namespace import
+	CheckNoNamespaceImport(t.Fatalf)
+
 	// Check size-prefixed flatbuffers
 	CheckSizePrefixedBuffer(t.Fatalf)
 
diff --git a/tests/include_test/order.fbs b/tests/include_test/order.fbs
new file mode 100644
index 00000000..4588d5fd
--- /dev/null
+++ b/tests/include_test/order.fbs
@@ -0,0 +1,8 @@
+include "no_namespace.fbs";
+
+namespace order;
+
+table Food {
+  pizza: Pizza (id: 0);
+  pizza_test:Pizza(id:1);
+}
diff --git a/tests/include_test/sub/no_namespace.fbs b/tests/include_test/sub/no_namespace.fbs
new file mode 100644
index 00000000..5f1052d1
--- /dev/null
+++ b/tests/include_test/sub/no_namespace.fbs
@@ -0,0 +1,3 @@
+table Pizza {
+  size: int;
+}
diff --git a/tests/order/Food.go b/tests/order/Food.go
new file mode 100644
index 00000000..298d6312
--- /dev/null
+++ b/tests/order/Food.go
@@ -0,0 +1,102 @@
+// Code generated by the FlatBuffers compiler. DO NOT EDIT.
+
+package order
+
+import (
+	flatbuffers "github.com/google/flatbuffers/go"
+
+	Pizza "Pizza"
+)
+
+type FoodT struct {
+	Pizza *Pizza.PizzaT `json:"pizza"`
+	PizzaTest *Pizza.PizzaT `json:"pizza_test"`
+}
+
+func (t *FoodT) Pack(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
+	if t == nil { return 0 }
+	pizzaOffset := t.Pizza.Pack(builder)
+	pizzaTestOffset := t.PizzaTest.Pack(builder)
+	FoodStart(builder)
+	FoodAddPizza(builder, pizzaOffset)
+	FoodAddPizzaTest(builder, pizzaTestOffset)
+	return FoodEnd(builder)
+}
+
+func (rcv *Food) UnPackTo(t *FoodT) {
+	t.Pizza = rcv.Pizza(nil).UnPack()
+	t.PizzaTest = rcv.PizzaTest(nil).UnPack()
+}
+
+func (rcv *Food) UnPack() *FoodT {
+	if rcv == nil { return nil }
+	t := &FoodT{}
+	rcv.UnPackTo(t)
+	return t
+}
+
+type Food struct {
+	_tab flatbuffers.Table
+}
+
+func GetRootAsFood(buf []byte, offset flatbuffers.UOffsetT) *Food {
+	n := flatbuffers.GetUOffsetT(buf[offset:])
+	x := &Food{}
+	x.Init(buf, n+offset)
+	return x
+}
+
+func GetSizePrefixedRootAsFood(buf []byte, offset flatbuffers.UOffsetT) *Food {
+	n := flatbuffers.GetUOffsetT(buf[offset+flatbuffers.SizeUint32:])
+	x := &Food{}
+	x.Init(buf, n+offset+flatbuffers.SizeUint32)
+	return x
+}
+
+func (rcv *Food) Init(buf []byte, i flatbuffers.UOffsetT) {
+	rcv._tab.Bytes = buf
+	rcv._tab.Pos = i
+}
+
+func (rcv *Food) Table() flatbuffers.Table {
+	return rcv._tab
+}
+
+func (rcv *Food) Pizza(obj *Pizza.Pizza) *Pizza.Pizza {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(4))
+	if o != 0 {
+		x := rcv._tab.Indirect(o + rcv._tab.Pos)
+		if obj == nil {
+			obj = new(Pizza.Pizza)
+		}
+		obj.Init(rcv._tab.Bytes, x)
+		return obj
+	}
+	return nil
+}
+
+func (rcv *Food) PizzaTest(obj *Pizza.Pizza) *Pizza.Pizza {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(6))
+	if o != 0 {
+		x := rcv._tab.Indirect(o + rcv._tab.Pos)
+		if obj == nil {
+			obj = new(Pizza.Pizza)
+		}
+		obj.Init(rcv._tab.Bytes, x)
+		return obj
+	}
+	return nil
+}
+
+func FoodStart(builder *flatbuffers.Builder) {
+	builder.StartObject(2)
+}
+func FoodAddPizza(builder *flatbuffers.Builder, pizza flatbuffers.UOffsetT) {
+	builder.PrependUOffsetTSlot(0, flatbuffers.UOffsetT(pizza), 0)
+}
+func FoodAddPizzaTest(builder *flatbuffers.Builder, pizzaTest flatbuffers.UOffsetT) {
+	builder.PrependUOffsetTSlot(1, flatbuffers.UOffsetT(pizzaTest), 0)
+}
+func FoodEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
+	return builder.EndObject()
+}