Esempio n. 1
0
func equalType(x, y types.Type) error {
	if reflect.TypeOf(x) != reflect.TypeOf(y) {
		return fmt.Errorf("unequal kinds: %T vs %T", x, y)
	}
	switch x := x.(type) {
	case *types.Interface:
		y := y.(*types.Interface)
		// TODO(gri): enable separate emission of Embedded interfaces
		// and ExplicitMethods then use this logic.
		// if x.NumEmbeddeds() != y.NumEmbeddeds() {
		// 	return fmt.Errorf("unequal number of embedded interfaces: %d vs %d",
		// 		x.NumEmbeddeds(), y.NumEmbeddeds())
		// }
		// for i := 0; i < x.NumEmbeddeds(); i++ {
		// 	xi := x.Embedded(i)
		// 	yi := y.Embedded(i)
		// 	if xi.String() != yi.String() {
		// 		return fmt.Errorf("mismatched %th embedded interface: %s vs %s",
		// 			i, xi, yi)
		// 	}
		// }
		// if x.NumExplicitMethods() != y.NumExplicitMethods() {
		// 	return fmt.Errorf("unequal methods: %d vs %d",
		// 		x.NumExplicitMethods(), y.NumExplicitMethods())
		// }
		// for i := 0; i < x.NumExplicitMethods(); i++ {
		// 	xm := x.ExplicitMethod(i)
		// 	ym := y.ExplicitMethod(i)
		// 	if xm.Name() != ym.Name() {
		// 		return fmt.Errorf("mismatched %th method: %s vs %s", i, xm, ym)
		// 	}
		// 	if err := equalType(xm.Type(), ym.Type()); err != nil {
		// 		return fmt.Errorf("mismatched %s method: %s", xm.Name(), err)
		// 	}
		// }
		if x.NumMethods() != y.NumMethods() {
			return fmt.Errorf("unequal methods: %d vs %d",
				x.NumMethods(), y.NumMethods())
		}
		for i := 0; i < x.NumMethods(); i++ {
			xm := x.Method(i)
			ym := y.Method(i)
			if xm.Name() != ym.Name() {
				return fmt.Errorf("mismatched %dth method: %s vs %s", i, xm, ym)
			}
			if err := equalType(xm.Type(), ym.Type()); err != nil {
				return fmt.Errorf("mismatched %s method: %s", xm.Name(), err)
			}
		}
	case *types.Array:
		y := y.(*types.Array)
		if x.Len() != y.Len() {
			return fmt.Errorf("unequal array lengths: %d vs %d", x.Len(), y.Len())
		}
		if err := equalType(x.Elem(), y.Elem()); err != nil {
			return fmt.Errorf("array elements: %s", err)
		}
	case *types.Basic:
		y := y.(*types.Basic)
		if x.Kind() != y.Kind() {
			return fmt.Errorf("unequal basic types: %s vs %s", x, y)
		}
	case *types.Chan:
		y := y.(*types.Chan)
		if x.Dir() != y.Dir() {
			return fmt.Errorf("unequal channel directions: %d vs %d", x.Dir(), y.Dir())
		}
		if err := equalType(x.Elem(), y.Elem()); err != nil {
			return fmt.Errorf("channel elements: %s", err)
		}
	case *types.Map:
		y := y.(*types.Map)
		if err := equalType(x.Key(), y.Key()); err != nil {
			return fmt.Errorf("map keys: %s", err)
		}
		if err := equalType(x.Elem(), y.Elem()); err != nil {
			return fmt.Errorf("map values: %s", err)
		}
	case *types.Named:
		y := y.(*types.Named)
		if x.String() != y.String() {
			return fmt.Errorf("unequal named types: %s vs %s", x, y)
		}
	case *types.Pointer:
		y := y.(*types.Pointer)
		if err := equalType(x.Elem(), y.Elem()); err != nil {
			return fmt.Errorf("pointer elements: %s", err)
		}
	case *types.Signature:
		y := y.(*types.Signature)
		if err := equalType(x.Params(), y.Params()); err != nil {
			return fmt.Errorf("parameters: %s", err)
		}
		if err := equalType(x.Results(), y.Results()); err != nil {
			return fmt.Errorf("results: %s", err)
		}
		if x.Variadic() != y.Variadic() {
			return fmt.Errorf("unequal varidicity: %t vs %t",
				x.Variadic(), y.Variadic())
		}
		if (x.Recv() != nil) != (y.Recv() != nil) {
			return fmt.Errorf("unequal receivers: %s vs %s", x.Recv(), y.Recv())
		}
		if x.Recv() != nil {
			// TODO(adonovan): fix: this assertion fires for interface methods.
			// The type of the receiver of an interface method is a named type
			// if the Package was loaded from export data, or an unnamed (interface)
			// type if the Package was produced by type-checking ASTs.
			// if err := equalType(x.Recv().Type(), y.Recv().Type()); err != nil {
			// 	return fmt.Errorf("receiver: %s", err)
			// }
		}
	case *types.Slice:
		y := y.(*types.Slice)
		if err := equalType(x.Elem(), y.Elem()); err != nil {
			return fmt.Errorf("slice elements: %s", err)
		}
	case *types.Struct:
		y := y.(*types.Struct)
		if x.NumFields() != y.NumFields() {
			return fmt.Errorf("unequal struct fields: %d vs %d",
				x.NumFields(), y.NumFields())
		}
		for i := 0; i < x.NumFields(); i++ {
			xf := x.Field(i)
			yf := y.Field(i)
			if xf.Name() != yf.Name() {
				return fmt.Errorf("mismatched fields: %s vs %s", xf, yf)
			}
			if err := equalType(xf.Type(), yf.Type()); err != nil {
				return fmt.Errorf("struct field %s: %s", xf.Name(), err)
			}
			if x.Tag(i) != y.Tag(i) {
				return fmt.Errorf("struct field %s has unequal tags: %q vs %q",
					xf.Name(), x.Tag(i), y.Tag(i))
			}
		}
	case *types.Tuple:
		y := y.(*types.Tuple)
		if x.Len() != y.Len() {
			return fmt.Errorf("unequal tuple lengths: %d vs %d", x.Len(), y.Len())
		}
		for i := 0; i < x.Len(); i++ {
			if err := equalType(x.At(i).Type(), y.At(i).Type()); err != nil {
				return fmt.Errorf("tuple element %d: %s", i, err)
			}
		}
	}
	return nil
}
Esempio n. 2
0
// matchArgTypeInternal is the internal version of matchArgType. It carries a map
// remembering what types are in progress so we don't recur when faced with recursive
// types or mutually recursive types.
func (f *File) matchArgTypeInternal(t printfArgType, typ types.Type, arg ast.Expr, inProgress map[types.Type]bool) bool {
	// %v, %T accept any argument type.
	if t == anyType {
		return true
	}
	if typ == nil {
		// external call
		typ = f.pkg.types[arg].Type
		if typ == nil {
			return true // probably a type check problem
		}
	}
	// If the type implements fmt.Formatter, we have nothing to check.
	// formatterTyp may be nil - be conservative and check for Format method in that case.
	if formatterType != nil && types.Implements(typ, formatterType) || f.hasMethod(typ, "Format") {
		return true
	}
	// If we can use a string, might arg (dynamically) implement the Stringer or Error interface?
	if t&argString != 0 {
		if types.AssertableTo(errorType, typ) || stringerType != nil && types.AssertableTo(stringerType, typ) {
			return true
		}
	}

	typ = typ.Underlying()
	if inProgress[typ] {
		// We're already looking at this type. The call that started it will take care of it.
		return true
	}
	inProgress[typ] = true

	switch typ := typ.(type) {
	case *types.Signature:
		return t&argPointer != 0

	case *types.Map:
		// Recur: map[int]int matches %d.
		return t&argPointer != 0 ||
			(f.matchArgTypeInternal(t, typ.Key(), arg, inProgress) && f.matchArgTypeInternal(t, typ.Elem(), arg, inProgress))

	case *types.Chan:
		return t&argPointer != 0

	case *types.Array:
		// Same as slice.
		if types.Identical(typ.Elem().Underlying(), types.Typ[types.Byte]) && t&argString != 0 {
			return true // %s matches []byte
		}
		// Recur: []int matches %d.
		return t&argPointer != 0 || f.matchArgTypeInternal(t, typ.Elem().Underlying(), arg, inProgress)

	case *types.Slice:
		// Same as array.
		if types.Identical(typ.Elem().Underlying(), types.Typ[types.Byte]) && t&argString != 0 {
			return true // %s matches []byte
		}
		// Recur: []int matches %d. But watch out for
		//	type T []T
		// If the element is a pointer type (type T[]*T), it's handled fine by the Pointer case below.
		return t&argPointer != 0 || f.matchArgTypeInternal(t, typ.Elem(), arg, inProgress)

	case *types.Pointer:
		// Ugly, but dealing with an edge case: a known pointer to an invalid type,
		// probably something from a failed import.
		if typ.Elem().String() == "invalid type" {
			if *verbose {
				f.Warnf(arg.Pos(), "printf argument %v is pointer to invalid or unknown type", f.gofmt(arg))
			}
			return true // special case
		}
		// If it's actually a pointer with %p, it prints as one.
		if t == argPointer {
			return true
		}
		// If it's pointer to struct, that's equivalent in our analysis to whether we can print the struct.
		if str, ok := typ.Elem().Underlying().(*types.Struct); ok {
			return f.matchStructArgType(t, str, arg, inProgress)
		}
		// The rest can print with %p as pointers, or as integers with %x etc.
		return t&(argInt|argPointer) != 0

	case *types.Struct:
		return f.matchStructArgType(t, typ, arg, inProgress)

	case *types.Interface:
		// If the static type of the argument is empty interface, there's little we can do.
		// Example:
		//	func f(x interface{}) { fmt.Printf("%s", x) }
		// Whether x is valid for %s depends on the type of the argument to f. One day
		// we will be able to do better. For now, we assume that empty interface is OK
		// but non-empty interfaces, with Stringer and Error handled above, are errors.
		return typ.NumMethods() == 0

	case *types.Basic:
		switch typ.Kind() {
		case types.UntypedBool,
			types.Bool:
			return t&argBool != 0

		case types.UntypedInt,
			types.Int,
			types.Int8,
			types.Int16,
			types.Int32,
			types.Int64,
			types.Uint,
			types.Uint8,
			types.Uint16,
			types.Uint32,
			types.Uint64,
			types.Uintptr:
			return t&argInt != 0

		case types.UntypedFloat,
			types.Float32,
			types.Float64:
			return t&argFloat != 0

		case types.UntypedComplex,
			types.Complex64,
			types.Complex128:
			return t&argComplex != 0

		case types.UntypedString,
			types.String:
			return t&argString != 0

		case types.UnsafePointer:
			return t&(argPointer|argInt) != 0

		case types.UntypedRune:
			return t&(argInt|argRune) != 0

		case types.UntypedNil:
			return t&argPointer != 0 // TODO?

		case types.Invalid:
			if *verbose {
				f.Warnf(arg.Pos(), "printf argument %v has invalid or unknown type", f.gofmt(arg))
			}
			return true // Probably a type check problem.
		}
		panic("unreachable")
	}

	return false
}
Esempio n. 3
0
func (w *Walker) writeType(buf *bytes.Buffer, typ types.Type) {
	switch typ := typ.(type) {
	case *types.Basic:
		s := typ.Name()
		switch typ.Kind() {
		case types.UnsafePointer:
			s = "unsafe.Pointer"
		case types.UntypedBool:
			s = "ideal-bool"
		case types.UntypedInt:
			s = "ideal-int"
		case types.UntypedRune:
			// "ideal-char" for compatibility with old tool
			// TODO(gri) change to "ideal-rune"
			s = "ideal-char"
		case types.UntypedFloat:
			s = "ideal-float"
		case types.UntypedComplex:
			s = "ideal-complex"
		case types.UntypedString:
			s = "ideal-string"
		case types.UntypedNil:
			panic("should never see untyped nil type")
		default:
			switch s {
			case "byte":
				s = "uint8"
			case "rune":
				s = "int32"
			}
		}
		buf.WriteString(s)

	case *types.Array:
		fmt.Fprintf(buf, "[%d]", typ.Len())
		w.writeType(buf, typ.Elem())

	case *types.Slice:
		buf.WriteString("[]")
		w.writeType(buf, typ.Elem())

	case *types.Struct:
		buf.WriteString("struct")

	case *types.Pointer:
		buf.WriteByte('*')
		w.writeType(buf, typ.Elem())

	case *types.Tuple:
		panic("should never see a tuple type")

	case *types.Signature:
		buf.WriteString("func")
		w.writeSignature(buf, typ)

	case *types.Interface:
		buf.WriteString("interface{")
		if typ.NumMethods() > 0 {
			buf.WriteByte(' ')
			buf.WriteString(strings.Join(sortedMethodNames(typ), ", "))
			buf.WriteByte(' ')
		}
		buf.WriteString("}")

	case *types.Map:
		buf.WriteString("map[")
		w.writeType(buf, typ.Key())
		buf.WriteByte(']')
		w.writeType(buf, typ.Elem())

	case *types.Chan:
		var s string
		switch typ.Dir() {
		case types.SendOnly:
			s = "chan<- "
		case types.RecvOnly:
			s = "<-chan "
		case types.SendRecv:
			s = "chan "
		default:
			panic("unreachable")
		}
		buf.WriteString(s)
		w.writeType(buf, typ.Elem())

	case *types.Named:
		obj := typ.Obj()
		pkg := obj.Pkg()
		if pkg != nil && pkg != w.current {
			buf.WriteString(pkg.Name())
			buf.WriteByte('.')
		}
		buf.WriteString(typ.Obj().Name())

	default:
		panic(fmt.Sprintf("unknown type %T", typ))
	}
}
Esempio n. 4
0
// hashFor computes the hash of t.
func (h Hasher) hashFor(t types.Type) uint32 {
	// See Identical for rationale.
	switch t := t.(type) {
	case *types.Basic:
		return uint32(t.Kind())

	case *types.Array:
		return 9043 + 2*uint32(t.Len()) + 3*h.Hash(t.Elem())

	case *types.Slice:
		return 9049 + 2*h.Hash(t.Elem())

	case *types.Struct:
		var hash uint32 = 9059
		for i, n := 0, t.NumFields(); i < n; i++ {
			f := t.Field(i)
			if f.Anonymous() {
				hash += 8861
			}
			hash += hashString(t.Tag(i))
			hash += hashString(f.Name()) // (ignore f.Pkg)
			hash += h.Hash(f.Type())
		}
		return hash

	case *types.Pointer:
		return 9067 + 2*h.Hash(t.Elem())

	case *types.Signature:
		var hash uint32 = 9091
		if t.Variadic() {
			hash *= 8863
		}
		return hash + 3*h.hashTuple(t.Params()) + 5*h.hashTuple(t.Results())

	case *types.Interface:
		var hash uint32 = 9103
		for i, n := 0, t.NumMethods(); i < n; i++ {
			// See go/types.identicalMethods for rationale.
			// Method order is not significant.
			// Ignore m.Pkg().
			m := t.Method(i)
			hash += 3*hashString(m.Name()) + 5*h.Hash(m.Type())
		}
		return hash

	case *types.Map:
		return 9109 + 2*h.Hash(t.Key()) + 3*h.Hash(t.Elem())

	case *types.Chan:
		return 9127 + 2*uint32(t.Dir()) + 3*h.Hash(t.Elem())

	case *types.Named:
		// Not safe with a copying GC; objects may move.
		return uint32(reflect.ValueOf(t.Obj()).Pointer())

	case *types.Tuple:
		return h.hashTuple(t)
	}
	panic(t)
}