// parent is the package which declared the type; parent == nil means
// the package currently imported. The parent package is needed for
// exported struct fields and interface methods which don't contain
// explicit package information in the export data.
func (p *importer) typ(parent *types.Package) types.Type {
	// if the type was seen before, i is its index (>= 0)
	i := p.tagOrIndex()
	if i >= 0 {
		return p.typList[i]
	}

	// otherwise, i is the type tag (< 0)
	switch i {
	case namedTag:
		// read type object
		name := p.string()
		parent = p.pkg()
		scope := parent.Scope()
		obj := scope.Lookup(name)

		// if the object doesn't exist yet, create and insert it
		if obj == nil {
			obj = types.NewTypeName(token.NoPos, parent, name, nil)
			scope.Insert(obj)
		}

		if _, ok := obj.(*types.TypeName); !ok {
			panic(fmt.Sprintf("pkg = %s, name = %s => %s", parent, name, obj))
		}

		// associate new named type with obj if it doesn't exist yet
		t0 := types.NewNamed(obj.(*types.TypeName), nil, nil)

		// but record the existing type, if any
		t := obj.Type().(*types.Named)
		p.record(t)

		// read underlying type
		t0.SetUnderlying(p.typ(parent))

		// interfaces don't have associated methods
		if _, ok := t0.Underlying().(*types.Interface); ok {
			return t
		}

		// read associated methods
		for i := p.int(); i > 0; i-- {
			name := p.string()
			recv, _ := p.paramList() // TODO(gri) do we need a full param list for the receiver?
			params, isddd := p.paramList()
			result, _ := p.paramList()
			p.int() // read and discard index of inlined function body
			sig := types.NewSignature(recv.At(0), params, result, isddd)
			t0.AddMethod(types.NewFunc(token.NoPos, parent, name, sig))
		}

		return t

	case arrayTag:
		t := new(types.Array)
		p.record(t)

		n := p.int64()
		*t = *types.NewArray(p.typ(parent), n)
		return t

	case sliceTag:
		t := new(types.Slice)
		p.record(t)

		*t = *types.NewSlice(p.typ(parent))
		return t

	case dddTag:
		t := new(dddSlice)
		p.record(t)

		t.elem = p.typ(parent)
		return t

	case structTag:
		t := new(types.Struct)
		p.record(t)

		n := p.int()
		fields := make([]*types.Var, n)
		tags := make([]string, n)
		for i := range fields {
			fields[i] = p.field(parent)
			tags[i] = p.string()
		}
		*t = *types.NewStruct(fields, tags)
		return t

	case pointerTag:
		t := new(types.Pointer)
		p.record(t)

		*t = *types.NewPointer(p.typ(parent))
		return t

	case signatureTag:
		t := new(types.Signature)
		p.record(t)

		params, isddd := p.paramList()
		result, _ := p.paramList()
		*t = *types.NewSignature(nil, params, result, isddd)
		return t

	case interfaceTag:
		// Create a dummy entry in the type list. This is safe because we
		// cannot expect the interface type to appear in a cycle, as any
		// such cycle must contain a named type which would have been
		// first defined earlier.
		n := len(p.typList)
		p.record(nil)

		// no embedded interfaces with gc compiler
		if p.int() != 0 {
			panic("unexpected embedded interface")
		}

		// read methods
		methods := make([]*types.Func, p.int())
		for i := range methods {
			pkg, name := p.fieldName(parent)
			params, isddd := p.paramList()
			result, _ := p.paramList()
			sig := types.NewSignature(nil, params, result, isddd)
			methods[i] = types.NewFunc(token.NoPos, pkg, name, sig)
		}

		t := types.NewInterface(methods, nil)
		p.typList[n] = t
		return t

	case mapTag:
		t := new(types.Map)
		p.record(t)

		key := p.typ(parent)
		val := p.typ(parent)
		*t = *types.NewMap(key, val)
		return t

	case chanTag:
		t := new(types.Chan)
		p.record(t)

		var dir types.ChanDir
		// tag values must match the constants in cmd/compile/internal/gc/go.go
		switch d := p.int(); d {
		case 1 /* Crecv */ :
			dir = types.RecvOnly
		case 2 /* Csend */ :
			dir = types.SendOnly
		case 3 /* Cboth */ :
			dir = types.SendRecv
		default:
			panic(fmt.Sprintf("unexpected channel dir %d", d))
		}
		val := p.typ(parent)
		*t = *types.NewChan(dir, val)
		return t

	default:
		panic(fmt.Sprintf("unexpected type tag %d", i))
	}
}
Beispiel #2
0
// parent is the package which declared the type; parent == nil means
// the package currently imported. The parent package is needed for
// exported struct fields and interface methods which don't contain
// explicit package information in the export data.
func (p *importer) typ(parent *types.Package) types.Type {
	// if the type was seen before, i is its index (>= 0)
	i := p.tagOrIndex()
	if i >= 0 {
		return p.typList[i]
	}

	// otherwise, i is the type tag (< 0)
	switch i {
	case namedTag:
		// read type object
		pos := p.pos()
		parent, name := p.qualifiedName()
		scope := parent.Scope()
		obj := scope.Lookup(name)

		// if the object doesn't exist yet, create and insert it
		if obj == nil {
			obj = types.NewTypeName(pos, parent, name, nil)
			scope.Insert(obj)
		}

		if _, ok := obj.(*types.TypeName); !ok {
			errorf("pkg = %s, name = %s => %s", parent, name, obj)
		}

		// associate new named type with obj if it doesn't exist yet
		t0 := types.NewNamed(obj.(*types.TypeName), nil, nil)

		// but record the existing type, if any
		t := obj.Type().(*types.Named)
		p.record(t)

		// read underlying type
		t0.SetUnderlying(p.typ(parent))

		// interfaces don't have associated methods
		if types.IsInterface(t0) {
			return t
		}

		// read associated methods
		for i := p.int(); i > 0; i-- {
			// TODO(gri) replace this with something closer to fieldName
			pos := p.pos()
			name := p.string()
			if !exported(name) {
				p.pkg()
			}

			recv, _ := p.paramList() // TODO(gri) do we need a full param list for the receiver?
			params, isddd := p.paramList()
			result, _ := p.paramList()
			p.int() // go:nointerface pragma - discarded

			sig := types.NewSignature(recv.At(0), params, result, isddd)
			t0.AddMethod(types.NewFunc(pos, parent, name, sig))
		}

		return t

	case arrayTag:
		t := new(types.Array)
		if p.trackAllTypes {
			p.record(t)
		}

		n := p.int64()
		*t = *types.NewArray(p.typ(parent), n)
		return t

	case sliceTag:
		t := new(types.Slice)
		if p.trackAllTypes {
			p.record(t)
		}

		*t = *types.NewSlice(p.typ(parent))
		return t

	case dddTag:
		t := new(dddSlice)
		if p.trackAllTypes {
			p.record(t)
		}

		t.elem = p.typ(parent)
		return t

	case structTag:
		t := new(types.Struct)
		if p.trackAllTypes {
			p.record(t)
		}

		*t = *types.NewStruct(p.fieldList(parent))
		return t

	case pointerTag:
		t := new(types.Pointer)
		if p.trackAllTypes {
			p.record(t)
		}

		*t = *types.NewPointer(p.typ(parent))
		return t

	case signatureTag:
		t := new(types.Signature)
		if p.trackAllTypes {
			p.record(t)
		}

		params, isddd := p.paramList()
		result, _ := p.paramList()
		*t = *types.NewSignature(nil, params, result, isddd)
		return t

	case interfaceTag:
		// Create a dummy entry in the type list. This is safe because we
		// cannot expect the interface type to appear in a cycle, as any
		// such cycle must contain a named type which would have been
		// first defined earlier.
		n := len(p.typList)
		if p.trackAllTypes {
			p.record(nil)
		}

		// no embedded interfaces with gc compiler
		if p.int() != 0 {
			errorf("unexpected embedded interface")
		}

		t := types.NewInterface(p.methodList(parent), nil)
		if p.trackAllTypes {
			p.typList[n] = t
		}
		return t

	case mapTag:
		t := new(types.Map)
		if p.trackAllTypes {
			p.record(t)
		}

		key := p.typ(parent)
		val := p.typ(parent)
		*t = *types.NewMap(key, val)
		return t

	case chanTag:
		t := new(types.Chan)
		if p.trackAllTypes {
			p.record(t)
		}

		var dir types.ChanDir
		// tag values must match the constants in cmd/compile/internal/gc/go.go
		switch d := p.int(); d {
		case 1 /* Crecv */ :
			dir = types.RecvOnly
		case 2 /* Csend */ :
			dir = types.SendOnly
		case 3 /* Cboth */ :
			dir = types.SendRecv
		default:
			errorf("unexpected channel dir %d", d)
		}
		val := p.typ(parent)
		*t = *types.NewChan(dir, val)
		return t

	default:
		errorf("unexpected type tag %d", i) // panics
		panic("unreachable")
	}
}