func WriteInterfaces(dependencies []*types.Package, w io.Writer, merge bool) {
allTypeNames := []*types.TypeName{types.New("error").(*types.Named).Obj()}
for _, dep := range dependencies {
scope := dep.Scope()
for _, name := range scope.Names() {
if typeName, isTypeName := scope.Lookup(name).(*types.TypeName); isTypeName {
allTypeNames = append(allTypeNames, typeName)
}
}
}
for _, t := range allTypeNames {
if in, isInterface := t.Type().Underlying().(*types.Interface); isInterface {
if in.MethodSet().Len() == 0 {
continue
}
implementedBy := make(map[string]bool, 0)
for _, other := range allTypeNames {
otherType := other.Type()
switch otherType.Underlying().(type) {
case *types.Interface:
// skip
case *types.Struct:
if types.IsAssignableTo(otherType, in) {
implementedBy[fmt.Sprintf("Go$packages[\"%s\"].%s.Go$NonPointer", other.Pkg().Path(), other.Name())] = true
}
if types.IsAssignableTo(types.NewPointer(otherType), in) {
implementedBy[fmt.Sprintf("Go$packages[\"%s\"].%s", other.Pkg().Path(), other.Name())] = true
}
default:
if types.IsAssignableTo(otherType, in) {
implementedBy[fmt.Sprintf("Go$packages[\"%s\"].%s", other.Pkg().Path(), other.Name())] = true
}
if types.IsAssignableTo(types.NewPointer(otherType), in) {
implementedBy[fmt.Sprintf("Go$packages[\"%s\"].%s.Go$Pointer", other.Pkg().Path(), other.Name())] = true
}
}
}
list := make([]string, 0, len(implementedBy))
for ref := range implementedBy {
list = append(list, ref)
}
sort.Strings(list)
var target string
switch t.Name() {
case "error":
target = "Go$error"
default:
target = fmt.Sprintf("Go$packages[\"%s\"].%s", t.Pkg().Path(), t.Name())
}
if merge {
for _, entry := range list {
fmt.Fprintf(w, "if (%s.Go$implementedBy.indexOf(%s) === -1) { %s.Go$implementedBy.push(%s); }\n", target, entry, target, entry)
}
continue
}
fmt.Fprintf(w, "%s.Go$implementedBy = [%s];\n", target, strings.Join(list, ", "))
}
}
}
func (c *typeAssertConstraint) solve(a *analysis, n *node, delta nodeset) {
tIface, _ := c.typ.Underlying().(*types.Interface)
for ifaceObj := range delta {
tDyn, v, indirect := a.taggedValue(ifaceObj)
if tDyn == nil {
panic("not a tagged value")
}
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
if tIface != nil {
if types.IsAssignableTo(tDyn, tIface) {
if a.addLabel(c.dst, ifaceObj) {
a.addWork(c.dst)
}
}
} else {
if types.IsIdentical(tDyn, c.typ) {
// Copy entire payload to dst.
//
// TODO(adonovan): opt: if tConc is
// nonpointerlike we can skip this
// entire constraint, perhaps. We
// only care about pointers among the
// fields.
a.onlineCopyN(c.dst, v, a.sizeof(tDyn))
}
}
}
}
// Implements displays the 'implements" relation among all
// package-level named types in the package containing the query
// position.
//
// TODO(adonovan): more features:
// - should we include pairs of types belonging to
// different packages in the 'implements' relation?
// - should we restrict the query to the type declaration identified
// by the query position, if any, and use all types in the package
// otherwise?
// - should we show types that are local to functions?
// They can only have methods via promotion.
// - abbreviate the set of concrete types implementing the empty
// interface.
// - should we scan the instruction stream for MakeInterface
// instructions and report which concrete->interface conversions
// actually occur, with examples? (NB: this is not a conservative
// answer due to ChangeInterface, i.e. subtyping among interfaces.)
//
func implements(o *Oracle, qpos *QueryPos) (queryResult, error) {
pkg := qpos.info.Pkg
// Compute set of named interface/concrete types at package level.
var interfaces, concretes []*types.Named
scope := pkg.Scope()
for _, name := range scope.Names() {
mem := scope.Lookup(name)
if t, ok := mem.(*types.TypeName); ok {
nt := t.Type().(*types.Named)
if _, ok := nt.Underlying().(*types.Interface); ok {
interfaces = append(interfaces, nt)
} else {
concretes = append(concretes, nt)
}
}
}
// For each interface, show the concrete types that implement it.
var facts []implementsFact
for _, iface := range interfaces {
fact := implementsFact{iface: iface}
for _, conc := range concretes {
if types.IsAssignableTo(conc, iface) {
fact.conc = conc
} else if ptr := types.NewPointer(conc); types.IsAssignableTo(ptr, iface) {
fact.conc = ptr
} else {
continue
}
facts = append(facts, fact)
}
}
// TODO(adonovan): sort facts to ensure test nondeterminism.
return &implementsResult{o.prog.Fset, facts}, nil
}
func (c *typeFilterConstraint) solve(a *analysis, n *node, delta nodeset) {
for ifaceObj := range delta {
tDyn, _, indirect := a.taggedValue(ifaceObj)
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
if types.IsAssignableTo(tDyn, c.typ) {
if a.addLabel(c.dst, ifaceObj) {
a.addWork(c.dst)
}
}
}
}
// Implements displays the "implements" relation as it pertains to the
// selected type.
//
func implements(o *Oracle, qpos *QueryPos) (queryResult, error) {
// Find the selected type.
// TODO(adonovan): fix: make it work on qualified Idents too.
path, action := findInterestingNode(qpos.info, qpos.path)
if action != actionType {
return nil, fmt.Errorf("no type here")
}
T := qpos.info.TypeOf(path[0].(ast.Expr))
if T == nil {
return nil, fmt.Errorf("no type here")
}
// Find all named types, even local types (which can have
// methods via promotion) and the built-in "error".
//
// TODO(adonovan): include all packages in PTA scope too?
// i.e. don't reduceScope?
//
var allNamed []types.Type
for _, info := range o.typeInfo {
for id, obj := range info.Objects {
if obj, ok := obj.(*types.TypeName); ok && obj.Pos() == id.Pos() {
allNamed = append(allNamed, obj.Type())
}
}
}
allNamed = append(allNamed, types.Universe.Lookup("error").Type())
// Test each named type.
var to, from, fromPtr []types.Type
for _, U := range allNamed {
if isInterface(T) {
if T.MethodSet().Len() == 0 {
continue // empty interface
}
if isInterface(U) {
if U.MethodSet().Len() == 0 {
continue // empty interface
}
// T interface, U interface
if !types.IsIdentical(T, U) {
if types.IsAssignableTo(U, T) {
to = append(to, U)
}
if types.IsAssignableTo(T, U) {
from = append(from, U)
}
}
} else {
// T interface, U concrete
if types.IsAssignableTo(U, T) {
to = append(to, U)
} else if pU := types.NewPointer(U); types.IsAssignableTo(pU, T) {
to = append(to, pU)
}
}
} else if isInterface(U) {
if U.MethodSet().Len() == 0 {
continue // empty interface
}
// T concrete, U interface
if types.IsAssignableTo(T, U) {
from = append(from, U)
} else if pT := types.NewPointer(T); types.IsAssignableTo(pT, U) {
fromPtr = append(fromPtr, U)
}
}
}
var pos interface{} = qpos
if nt, ok := deref(T).(*types.Named); ok {
pos = nt.Obj()
}
// Sort types (arbitrarily) to ensure test nondeterminism.
sort.Sort(typesByString(to))
sort.Sort(typesByString(from))
sort.Sort(typesByString(fromPtr))
return &implementsResult{T, pos, to, from, fromPtr}, nil
}
