Added target test with already defined register

gen/target_test.go

@@ -0,0 +1,43 @@
+package gen_test
+
+import (
+	"testing"
+
+	"alon.kr/x/usm/core"
+	"alon.kr/x/usm/gen"
+	"alon.kr/x/usm/parse"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestTargetRegisterAlreadyDefined(t *testing.T) {
+	src := core.NewSourceView("$32 %a")
+	unmanaged := src.Unmanaged()
+	node := parse.TargetNode{
+		Register: parse.RegisterNode{
+			UnmanagedSourceView: unmanaged.Subview(4, 6),
+		},
+		Type: &parse.TypeNode{
+			Identifier: unmanaged.Subview(0, 3),
+		},
+	}
+
+	intType := &gen.TypeInfo{Name: "$32", Size: 4}
+	types := TypeMap{intType.Name: intType}
+
+	registers := RegisterMap{
+		"%a": &gen.RegisterInfo{Name: "%a", Type: intType},
+	}
+
+	ctx := gen.GenerationContext[Instruction]{
+		ArchInfo:      gen.ArchInfo{PointerSize: 8},
+		SourceContext: src.Ctx(),
+		Types:         &types,
+		Registers:     &registers,
+		Instructions:  &InstructionMap{},
+	}
+
+	generator := gen.TargetGenerator[Instruction]{}
+	info, results := generator.Generate(&ctx, node)
+	assert.True(t, results.IsEmpty())
+	assert.Equal(t, intType, info)
+}