package compiler_test import ( "math/big" "testing" "github.com/nspcc-dev/neo-go/pkg/vm/opcode" ) func TestGenDeclWithMultiRet(t *testing.T) { t.Run("global var decl", func(t *testing.T) { src := `package foo func Main() int { var a, b = f() return a + b } func f() (int, int) { return 1, 2 }` eval(t, src, big.NewInt(3)) }) t.Run("local var decl", func(t *testing.T) { src := `package foo var a, b = f() func Main() int { return a + b } func f() (int, int) { return 1, 2 }` eval(t, src, big.NewInt(3)) }) } func TestUnderscoreLocalVarDontEmitCode(t *testing.T) { src := `package foo type Foo struct { Int int } func Main() int { var _ int var _ = 1 var ( A = 2 _ = A + 3 _, B, _ = 4, 5, 6 _, _, _ = f(A, B) // unused, but has function call, so the code is expected _, C, _ = f(A, B) ) var D = 7 // unused but named, so the code is expected _ = D var _ = Foo{ Int: 5 } var fo = Foo{ Int: 3 } var _ = 1 + A + fo.Int var _ = fo.GetInt() // unused, but has method call, so the code is expected return C } func f(a, b int) (int, int, int) { return 8, 9, 10 } func (fo Foo) GetInt() int { return fo.Int }` eval(t, src, big.NewInt(9), []interface{}{opcode.INITSLOT, []byte{5, 0}}, // local slot for A, B, C, D, fo opcode.PUSH2, opcode.STLOC0, // store A opcode.PUSH5, opcode.STLOC1, // store B opcode.LDLOC0, opcode.LDLOC1, opcode.SWAP, []interface{}{opcode.CALL, []byte{27}}, // evaluate f() first time opcode.DROP, opcode.DROP, opcode.DROP, // drop all values from f opcode.LDLOC0, opcode.LDLOC1, opcode.SWAP, []interface{}{opcode.CALL, []byte{19}}, // evaluate f() second time opcode.DROP, opcode.STLOC2, opcode.DROP, // store C opcode.PUSH7, opcode.STLOC3, // store D opcode.LDLOC3, opcode.DROP, // empty assignment opcode.PUSH3, opcode.PUSH1, opcode.PACKSTRUCT, opcode.STLOC4, // fo decl opcode.LDLOC4, []interface{}{opcode.CALL, []byte{12}}, opcode.DROP, // fo.GetInt() opcode.LDLOC2, opcode.RET, // return C []interface{}{opcode.INITSLOT, []byte{0, 2}}, opcode.PUSH10, opcode.PUSH9, opcode.PUSH8, opcode.RET, // f []interface{}{opcode.INITSLOT, []byte{0, 1}}, opcode.LDARG0, opcode.PUSH0, opcode.PICKITEM, opcode.RET) // (fo Foo) GetInt() int }