trap_test.go

package wasmtime

import "testing"

func TestTrap(t *testing.T) {
	trap := NewTrap("message")
	if trap.Message() != "message" {
		panic("wrong message")
	}
}

func TestTrapFrames(t *testing.T) {
	store := NewStore(NewEngine())
	wasm, err := Wat2Wasm(`
	  (func call $foo)
	  (func $foo call $bar)
	  (func $bar unreachable)
	  (start 0)
	`)
	assertNoError(err)
	module, err := NewModule(store.Engine, wasm)
	assertNoError(err)

	i, err := NewInstance(store, module, []AsExtern{})
	if i != nil {
		panic("expected failure")
	}
	if err == nil {
		panic("expected failure")
	}
	trap := err.(*Trap)
	frames := trap.Frames()
	if len(frames) != 3 {
		panic("expected 3 frames")
	}
	if *frames[0].FuncName() != "bar" {
		panic("bad function name")
	}
	if *frames[1].FuncName() != "foo" {
		panic("bad function name")
	}
	if frames[2].FuncName() != nil {
		panic("bad function name")
	}
	if frames[0].FuncIndex() != 2 {
		panic("bad function index")
	}
	if frames[1].FuncIndex() != 1 {
		panic("bad function index")
	}
	if frames[2].FuncIndex() != 0 {
		panic("bad function index")
	}

	expected := `wasm trap: wasm ` + "`unreachable`" + ` instruction executed
wasm backtrace:
    0:   0x26 - <unknown>!bar
    1:   0x21 - <unknown>!foo
    2:   0x1c - <unknown>!<wasm function 0>
`
	if trap.Error() != expected {
		t.Fatalf("expected\n%s\ngot\n%s", expected, trap.Error())
	}
	expCode := UnreachableCodeReached
	if code := trap.Code(); code != nil && *code != expCode {
		t.Fatalf("expected %v got %v", expCode, code)
	}
}

func TestTrapModuleName(t *testing.T) {
	store := NewStore(NewEngine())
	wasm, err := Wat2Wasm(`(module $f
	  (func unreachable)
	  (start 0)
	)`)
	assertNoError(err)
	module, err := NewModule(store.Engine, wasm)
	assertNoError(err)

	i, err := NewInstance(store, module, []AsExtern{})
	if i != nil {
		panic("expected failure")
	}
	if err == nil {
		panic("expected failure")
	}
	trap := err.(*Trap)
	frames := trap.Frames()
	if len(frames) != 1 {
		panic("expected 3 frames")
	}
	if *frames[0].ModuleName() != "f" {
		panic("bad module name")
	}
}