neoneo-go/pkg/compiler/global_test.go
Anna Shaleva 91b36657d6 compiler: do not emit code for unnamed unused variables
If variable is unnamed and does not contain function call then it's
treated as unused and code generation may be omitted for it
initialization/declaration.
2022-09-01 09:18:56 +03:00

378 lines
8.5 KiB
Go

package compiler_test
import (
"bytes"
"fmt"
"math/big"
"strings"
"testing"
"github.com/nspcc-dev/neo-go/pkg/compiler"
"github.com/nspcc-dev/neo-go/pkg/vm"
"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
"github.com/stretchr/testify/require"
)
func TestUnusedGlobal(t *testing.T) {
t.Run("simple unused", func(t *testing.T) {
src := `package foo
const (
_ int = iota
a
)
func Main() int {
return 1
}`
prog := eval(t, src, big.NewInt(1))
require.Equal(t, 2, len(prog)) // PUSH1 + RET
})
t.Run("unused with function call inside", func(t *testing.T) {
t.Run("specification names count matches values count", func(t *testing.T) {
src := `package foo
var control int
var _ = f()
func Main() int {
return control
}
func f() int {
control = 1
return 5
}`
eval(t, src, big.NewInt(1))
})
t.Run("specification names count differs from values count", func(t *testing.T) {
src := `package foo
var control int
var _, _ = f()
func Main() int {
return control
}
func f() (int, int) {
control = 1
return 5, 6
}`
eval(t, src, big.NewInt(1))
})
t.Run("used", func(t *testing.T) {
src := `package foo
var _, A = f()
func Main() int {
return A
}
func f() (int, int) {
return 5, 6
}`
eval(t, src, big.NewInt(6))
})
})
t.Run("unused without function call", func(t *testing.T) {
src := `package foo
var _ = 1
var (
_ = 2 + 3
_, _ = 3 + 4, 5
)
func Main() int {
return 1
}`
prog := eval(t, src, big.NewInt(1))
require.Equal(t, 2, len(prog)) // PUSH1 + RET
})
}
func TestChangeGlobal(t *testing.T) {
src := `package foo
var a int
func Main() int {
setLocal()
set42()
setLocal()
return a
}
func set42() { a = 42 }
func setLocal() { a := 10; _ = a }`
eval(t, src, big.NewInt(42))
}
func TestMultiDeclaration(t *testing.T) {
src := `package foo
var a, b, c int
func Main() int {
a = 1
b = 2
c = 3
return a + b + c
}`
eval(t, src, big.NewInt(6))
}
func TestCountLocal(t *testing.T) {
src := `package foo
func Main() int {
a, b, c, d := f()
return a + b + c + d
}
func f() (int, int, int, int) {
return 1, 2, 3, 4
}`
eval(t, src, big.NewInt(10))
}
func TestMultiDeclarationLocal(t *testing.T) {
src := `package foo
func Main() int {
var a, b, c int
a = 1
b = 2
c = 3
return a + b + c
}`
eval(t, src, big.NewInt(6))
}
func TestMultiDeclarationLocalCompound(t *testing.T) {
src := `package foo
func Main() int {
var a, b, c []int
a = append(a, 1)
b = append(b, 2)
c = append(c, 3)
return a[0] + b[0] + c[0]
}`
eval(t, src, big.NewInt(6))
}
func TestShadow(t *testing.T) {
srcTmpl := `package foo
func Main() int {
x := 1
y := 10
%s
x += 1 // increase old local
x := 30 // introduce new local
y += x // make sure is means something
}
return x+y
}`
runCase := func(b string) func(t *testing.T) {
return func(t *testing.T) {
src := fmt.Sprintf(srcTmpl, b)
eval(t, src, big.NewInt(42))
}
}
t.Run("If", runCase("if true {"))
t.Run("For", runCase("for i := 0; i < 1; i++ {"))
t.Run("Range", runCase("for range []int{1} {"))
t.Run("Switch", runCase("switch true {\ncase false: x += 2\ncase true:"))
t.Run("Block", runCase("{"))
}
func TestArgumentLocal(t *testing.T) {
srcTmpl := `package foo
func some(a int) int {
if a > 42 {
a := 24
_ = a
}
return a
}
func Main() int {
return some(%d)
}`
t.Run("Override", func(t *testing.T) {
src := fmt.Sprintf(srcTmpl, 50)
eval(t, src, big.NewInt(50))
})
t.Run("NoOverride", func(t *testing.T) {
src := fmt.Sprintf(srcTmpl, 40)
eval(t, src, big.NewInt(40))
})
}
func TestContractWithNoMain(t *testing.T) {
src := `package foo
var someGlobal int = 1
func Add3(a int) int {
someLocal := 2
return someGlobal + someLocal + a
}`
b, di, err := compiler.CompileWithOptions("foo.go", strings.NewReader(src), nil)
require.NoError(t, err)
v := vm.New()
invokeMethod(t, "Add3", b.Script, v, di)
v.Estack().PushVal(39)
require.NoError(t, v.Run())
require.Equal(t, 1, v.Estack().Len())
require.Equal(t, big.NewInt(42), v.PopResult())
}
func TestMultipleFiles(t *testing.T) {
src := `package foo
import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/multi"
func Main() int {
return multi.Sum()
}`
eval(t, src, big.NewInt(42))
}
func TestExportedVariable(t *testing.T) {
t.Run("Use", func(t *testing.T) {
src := `package foo
import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/multi"
func Main() int {
return multi.SomeVar12
}`
eval(t, src, big.NewInt(12))
})
t.Run("ChangeAndUse", func(t *testing.T) {
src := `package foo
import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/multi"
func Main() int {
multi.SomeVar12 = 10
return multi.Sum()
}`
eval(t, src, big.NewInt(40))
})
t.Run("PackageAlias", func(t *testing.T) {
src := `package foo
import kek "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/multi"
func Main() int {
kek.SomeVar12 = 10
return kek.Sum()
}`
eval(t, src, big.NewInt(40))
})
t.Run("DifferentName", func(t *testing.T) {
src := `package foo
import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/strange"
func Main() int {
normal.NormalVar = 42
return normal.NormalVar
}`
eval(t, src, big.NewInt(42))
})
t.Run("MultipleEqualNames", func(t *testing.T) {
src := `package foo
import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/multi"
var SomeVar12 = 1
func Main() int {
SomeVar30 := 3
sum := SomeVar12 + multi.SomeVar30
sum += SomeVar30
sum += multi.SomeVar12
return sum
}`
eval(t, src, big.NewInt(46))
})
}
func TestExportedConst(t *testing.T) {
t.Run("with vars", func(t *testing.T) {
src := `package foo
import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/multi"
func Main() int {
return multi.SomeConst
}`
eval(t, src, big.NewInt(42))
})
t.Run("const only", func(t *testing.T) {
src := `package foo
import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/constonly"
func Main() int {
return constonly.Answer
}`
eval(t, src, big.NewInt(42))
})
}
func TestMultipleFuncSameName(t *testing.T) {
t.Run("Simple", func(t *testing.T) {
src := `package foo
import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/multi"
func Main() int {
return multi.Sum() + Sum()
}
func Sum() int {
return 11
}`
eval(t, src, big.NewInt(53))
})
t.Run("WithMethod", func(t *testing.T) {
src := `package foo
import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/foo"
type Foo struct{}
func (f Foo) Bar() int { return 11 }
func Bar() int { return 22 }
func Main() int {
var a Foo
var b foo.Foo
return a.Bar() + // 11
foo.Bar() + // 1
b.Bar() + // 8
Bar() // 22
}`
eval(t, src, big.NewInt(42))
})
}
func TestConstDontUseSlots(t *testing.T) {
const count = 256
buf := bytes.NewBufferString("package foo\n")
for i := 0; i < count; i++ {
buf.WriteString(fmt.Sprintf("const n%d = 1\n", i))
}
buf.WriteString("func Main() int { sum := 0\n")
for i := 0; i < count; i++ {
buf.WriteString(fmt.Sprintf("sum += n%d\n", i))
}
buf.WriteString("return sum }")
src := buf.String()
eval(t, src, big.NewInt(count))
}
func TestUnderscoreVarsDontUseSlots(t *testing.T) {
const count = 128
buf := bytes.NewBufferString("package foo\n")
for i := 0; i < count; i++ {
buf.WriteString(fmt.Sprintf("var _, n%d = 1, 1\n", i))
}
buf.WriteString("func Main() int { sum := 0\n")
for i := 0; i < count; i++ {
buf.WriteString(fmt.Sprintf("sum += n%d\n", i))
}
buf.WriteString("return sum }")
src := buf.String()
eval(t, src, big.NewInt(count))
}
func TestUnderscoreGlobalVarDontEmitCode(t *testing.T) {
src := `package foo
var _ int
var _ = 1
var (
A = 2
_ = A + 3
_, B, _ = 4, 5, 6
_, C, _ = f(A, B)
)
var D = 7 // unused but named, so the code is expected
func Main() int {
return 1
}
func f(a, b int) (int, int, int) {
return 8, 9, 10
}`
eval(t, src, big.NewInt(1), []interface{}{opcode.INITSSLOT, []byte{4}}, // sslot for A, B, C, D
opcode.PUSH2, opcode.STSFLD0, // store A
opcode.PUSH5, opcode.STSFLD1, // store B
opcode.LDSFLD0, opcode.LDSFLD1, opcode.SWAP, []interface{}{opcode.CALL, []byte{10}}, // evaluate f
opcode.DROP, opcode.STSFLD2, opcode.DROP, // store C
opcode.PUSH7, opcode.STSFLD3, opcode.RET, // store D
opcode.PUSH1, opcode.RET, // Main
[]interface{}{opcode.INITSLOT, []byte{0, 2}}, opcode.PUSH10, opcode.PUSH9, opcode.PUSH8, opcode.RET) // f
}