// computeTrackBits sets a.track to the necessary 'track' bits for the pointer queries.
func (a *analysis) computeTrackBits() {
var queryTypes []types.Type
for v := range a.config.Queries {
queryTypes = append(queryTypes, v.Type())
}
for v := range a.config.IndirectQueries {
queryTypes = append(queryTypes, mustDeref(v.Type()))
}
for _, t := range queryTypes {
switch t.Underlying().(type) {
case *types.Chan:
a.track |= trackChan
case *types.Map:
a.track |= trackMap
case *types.Pointer:
a.track |= trackPtr
case *types.Slice:
a.track |= trackSlice
case *types.Interface:
a.track = trackAll
return
}
if rVObj := a.reflectValueObj; rVObj != nil && types.Identical(t, rVObj.Type()) {
a.track = trackAll
return
}
}
}
// containsAllIdsOf reports whether the method identifiers of T are a
// superset of those in U. If U belongs to an interface type, the
// result is equal to types.Assignable(T, U), but is cheaper to compute.
//
// TODO(gri): make this a method of *types.MethodSet.
//
func containsAllIdsOf(T, U *types.MethodSet) bool {
t, tlen := 0, T.Len()
u, ulen := 0, U.Len()
for t < tlen && u < ulen {
tMeth := T.At(t).Obj()
uMeth := U.At(u).Obj()
tId := tMeth.Id()
uId := uMeth.Id()
if tId > uId {
// U has a method T lacks: fail.
return false
}
if tId < uId {
// T has a method U lacks: ignore it.
t++
continue
}
// U and T both have a method of this Id. Check types.
if !types.Identical(tMeth.Type(), uMeth.Type()) {
return false // type mismatch
}
u++
t++
}
return u == ulen
}
// Set sets the map entry for key to val,
// and returns the previous entry, if any.
func (m *Map) Set(key types.Type, value interface{}) (prev interface{}) {
if m.table != nil {
hash := m.hasher.Hash(key)
bucket := m.table[hash]
var hole *entry
for i, e := range bucket {
if e.key == nil {
hole = &bucket[i]
} else if types.Identical(key, e.key) {
prev = e.value
bucket[i].value = value
return
}
}
if hole != nil {
*hole = entry{key, value} // overwrite deleted entry
} else {
m.table[hash] = append(bucket, entry{key, value})
}
} else {
if m.hasher.memo == nil {
m.hasher = MakeHasher()
}
hash := m.hasher.Hash(key)
m.table = map[uint32][]entry{hash: {entry{key, value}}}
}
m.length++
return
}
func (c *funcContext) translateImplicitConversion(expr ast.Expr, desiredType types.Type) *expression {
if desiredType == nil {
return c.translateExpr(expr)
}
exprType := c.p.TypeOf(expr)
if types.Identical(exprType, desiredType) {
return c.translateExpr(expr)
}
basicExprType, isBasicExpr := exprType.Underlying().(*types.Basic)
if isBasicExpr && basicExprType.Kind() == types.UntypedNil {
return c.formatExpr("%e", c.zeroValue(desiredType))
}
switch desiredType.Underlying().(type) {
case *types.Slice:
return c.formatExpr("$subslice(new %1s(%2e.$array), %2e.$offset, %2e.$offset + %2e.$length)", c.typeName(desiredType), expr)
case *types.Interface:
if typesutil.IsJsObject(exprType) {
// wrap JS object into js.Object struct when converting to interface
return c.formatExpr("new $jsObjectPtr(%e)", expr)
}
if isWrapped(exprType) {
return c.formatExpr("new %s(%e)", c.typeName(exprType), expr)
}
if _, isStruct := exprType.Underlying().(*types.Struct); isStruct {
return c.formatExpr("new %1e.constructor.elem(%1e)", expr)
}
}
return c.translateExpr(expr)
}
// assign records pairs of distinct types that are related by
// assignability, where the left-hand side is an interface and both
// sides have methods.
//
// It should be called for all assignability checks, type assertions,
// explicit conversions and comparisons between two types, unless the
// types are uninteresting (e.g. lhs is a concrete type, or the empty
// interface; rhs has no methods).
//
func (f *Finder) assign(lhs, rhs types.Type) {
if types.Identical(lhs, rhs) {
return
}
if !isInterface(lhs) {
return
}
if f.msetcache.MethodSet(lhs).Len() == 0 {
return
}
if f.msetcache.MethodSet(rhs).Len() == 0 {
return
}
// canonicalize types
lhsc, ok := f.canon.At(lhs).(types.Type)
if !ok {
lhsc = lhs
f.canon.Set(lhs, lhsc)
}
rhsc, ok := f.canon.At(rhs).(types.Type)
if !ok {
rhsc = rhs
f.canon.Set(rhs, rhsc)
}
// record the pair
f.Result[Constraint{lhsc, rhsc}] = true
}
// typeAssert checks whether dynamic type of itf is instr.AssertedType.
// It returns the extracted value on success, and panics on failure,
// unless instr.CommaOk, in which case it always returns a "value,ok" tuple.
//
func typeAssert(i *interpreter, instr *ssa.TypeAssert, itf iface) value {
var v value
err := ""
if itf.t == nil {
err = fmt.Sprintf("interface conversion: interface is nil, not %s", instr.AssertedType)
} else if idst, ok := instr.AssertedType.Underlying().(*types.Interface); ok {
v = itf
err = checkInterface(i, idst, itf)
} else if types.Identical(itf.t, instr.AssertedType) {
v = copyVal(itf.v) // extract value
} else {
err = fmt.Sprintf("interface conversion: interface is %s, not %s", itf.t, instr.AssertedType)
}
if err != "" {
if !instr.CommaOk {
panic(err)
}
return tuple{zero(instr.AssertedType), false}
}
if instr.CommaOk {
return tuple{v, true}
}
return v
}
func checkEqualButNotIdentical(t *testing.T, x, y types.Type, comment string) {
if !types.Identical(x, y) {
t.Errorf("%s: not equal: %s, %s", comment, x, y)
}
if x == y {
t.Errorf("%s: identical: %v, %v", comment, x, y)
}
}
// At returns the map entry for the given key.
// The result is nil if the entry is not present.
//
func (m *Map) At(key types.Type) interface{} {
if m != nil && m.table != nil {
for _, e := range m.table[m.hasher.Hash(key)] {
if e.key != nil && types.Identical(key, e.key) {
return e.value
}
}
}
return nil
}
// findAssignments returns the set of types to or from which type T is
// assigned in the program syntax.
func (r *renamer) findAssignments(T types.Type) map[types.Type]bool {
if r.satisfyConstraints == nil {
// Compute on demand: it's expensive.
var f satisfy.Finder
for _, info := range r.packages {
f.Find(&info.Info, info.Files)
}
r.satisfyConstraints = f.Result
}
result := make(map[types.Type]bool)
for key := range r.satisfyConstraints {
// key = (lhs, rhs) where lhs is always an interface.
if types.Identical(key.RHS, T) {
result[key.LHS] = true
}
if isInterface(T) && types.Identical(key.LHS, T) {
// must check both sides
result[key.RHS] = true
}
}
return result
}
func hasType(pkg *grinder.Package, fn *ast.FuncDecl, edit *grinder.EditBuffer, x, v ast.Expr) bool {
// Does x (by itself) default to v's type?
// Find the scope in which x appears.
xScope := pkg.Info.Scopes[fn.Type]
ast.Inspect(fn.Body, func(z ast.Node) bool {
if z == nil {
return false
}
if x.Pos() < z.Pos() || z.End() <= x.Pos() {
return false
}
scope := pkg.Info.Scopes[z]
if scope != nil {
xScope = scope
}
return true
})
xs := edit.TextAt(x.Pos(), x.End())
xt, err := types.Eval(pkg.FileSet, pkg.Types, xScope.Pos(), xs)
if err != nil {
return false
}
vt := pkg.Info.Types[v]
if types.Identical(xt.Type, vt.Type) {
return true
}
// Might be untyped.
vb, ok1 := vt.Type.(*types.Basic)
xb, ok2 := xt.Type.(*types.Basic)
if ok1 && ok2 {
switch xb.Kind() {
case types.UntypedInt:
return vb.Kind() == types.Int
case types.UntypedBool:
return vb.Kind() == types.Bool
case types.UntypedRune:
return vb.Kind() == types.Rune
case types.UntypedFloat:
return vb.Kind() == types.Float64
case types.UntypedComplex:
return vb.Kind() == types.Complex128
case types.UntypedString:
return vb.Kind() == types.String
}
}
return false
}
// Delete removes the entry with the given key, if any.
// It returns true if the entry was found.
//
func (m *Map) Delete(key types.Type) bool {
if m != nil && m.table != nil {
hash := m.hasher.Hash(key)
bucket := m.table[hash]
for i, e := range bucket {
if e.key != nil && types.Identical(key, e.key) {
// We can't compact the bucket as it
// would disturb iterators.
bucket[i] = entry{}
m.length--
return true
}
}
}
return false
}
// isErrorMethodCall reports whether the call is of a method with signature
// func Error() string
// where "string" is the universe's string type. We know the method is called "Error".
func (f *File) isErrorMethodCall(call *ast.CallExpr) bool {
typ := f.pkg.types[call].Type
if typ != nil {
// We know it's called "Error", so just check the function signature
// (stringerType has exactly one method, String).
if stringerType != nil && stringerType.NumMethods() == 1 {
return types.Identical(f.pkg.types[call.Fun].Type, stringerType.Method(0).Type())
}
}
// Without types, we can still check by hand.
// Is it a selector expression? Otherwise it's a function call, not a method call.
sel, ok := call.Fun.(*ast.SelectorExpr)
if !ok {
return false
}
// The package is type-checked, so if there are no arguments, we're done.
if len(call.Args) > 0 {
return false
}
// Check the type of the method declaration
typ = f.pkg.types[sel].Type
if typ == nil {
return false
}
// The type must be a signature, but be sure for safety.
sig, ok := typ.(*types.Signature)
if !ok {
return false
}
// There must be a receiver for it to be a method call. Otherwise it is
// a function, not something that satisfies the error interface.
if sig.Recv() == nil {
return false
}
// There must be no arguments. Already verified by type checking, but be thorough.
if sig.Params().Len() > 0 {
return false
}
// Finally the real questions.
// There must be one result.
if sig.Results().Len() != 1 {
return false
}
// It must have return type "string" from the universe.
return sig.Results().At(0).Type() == types.Typ[types.String]
}
// assign records pairs of distinct types that are related by
// assignability, where the left-hand side is an interface and both
// sides have methods.
//
// It should be called for all assignability checks, type assertions,
// explicit conversions and comparisons between two types, unless the
// types are uninteresting (e.g. lhs is a concrete type, or the empty
// interface; rhs has no methods).
//
func (f *Finder) assign(lhs, rhs types.Type) {
if types.Identical(lhs, rhs) {
return
}
if !isInterface(lhs) {
return
}
if f.msetcache.MethodSet(lhs).Len() == 0 {
return
}
if f.msetcache.MethodSet(rhs).Len() == 0 {
return
}
// record the pair
f.Result[Constraint{lhs, rhs}] = true
}
// isValuePreserving returns true if a conversion from ut_src to
// ut_dst is value-preserving, i.e. just a change of type.
// Precondition: neither argument is a named type.
//
func isValuePreserving(ut_src, ut_dst types.Type) bool {
// Identical underlying types?
if types.Identical(ut_dst, ut_src) {
return true
}
switch ut_dst.(type) {
case *types.Chan:
// Conversion between channel types?
_, ok := ut_src.(*types.Chan)
return ok
case *types.Pointer:
// Conversion between pointers with identical base types?
_, ok := ut_src.(*types.Pointer)
return ok
}
return false
}
func checkFuncValue(t *testing.T, prog *ssa.Program, obj *types.Func) {
fn := prog.FuncValue(obj)
// fmt.Printf("FuncValue(%s) = %s\n", obj, fn) // debugging
if fn == nil {
if obj.Name() != "interfaceMethod" {
t.Errorf("FuncValue(%s) == nil", obj)
}
return
}
if fnobj := fn.Object(); fnobj != obj {
t.Errorf("FuncValue(%s).Object() == %s; value was %s",
obj, fnobj, fn.Name())
return
}
if !types.Identical(fn.Type(), obj.Type()) {
t.Errorf("FuncValue(%s).Type() == %s", obj, fn.Type())
return
}
}
func checkConstValue(t *testing.T, prog *ssa.Program, obj *types.Const) {
c := prog.ConstValue(obj)
// fmt.Printf("ConstValue(%s) = %s\n", obj, c) // debugging
if c == nil {
t.Errorf("ConstValue(%s) == nil", obj)
return
}
if !types.Identical(c.Type(), obj.Type()) {
t.Errorf("ConstValue(%s).Type() == %s", obj, c.Type())
return
}
if obj.Name() != "nil" {
if !exact.Compare(c.Value, token.EQL, obj.Val()) {
t.Errorf("ConstValue(%s).Value (%s) != %s",
obj, c.Value, obj.Val())
return
}
}
}
// checkShadowing checks whether the identifier shadows an identifier in an outer scope.
func checkShadowing(f *File, ident *ast.Ident) {
if ident.Name == "_" {
// Can't shadow the blank identifier.
return
}
obj := f.pkg.defs[ident]
if obj == nil {
return
}
// obj.Parent.Parent is the surrounding scope. If we can find another declaration
// starting from there, we have a shadowed identifier.
_, shadowed := obj.Parent().Parent().LookupParent(obj.Name(), obj.Pos())
if shadowed == nil {
return
}
// Don't complain if it's shadowing a universe-declared identifier; that's fine.
if shadowed.Parent() == types.Universe {
return
}
if *strictShadowing {
// The shadowed identifier must appear before this one to be an instance of shadowing.
if shadowed.Pos() > ident.Pos() {
return
}
} else {
// Don't complain if the span of validity of the shadowed identifier doesn't include
// the shadowing identifier.
span, ok := f.pkg.spans[shadowed]
if !ok {
f.Badf(ident.Pos(), "internal error: no range for %s", ident.Name)
return
}
if !span.contains(ident.Pos()) {
return
}
}
// Don't complain if the types differ: that implies the programmer really wants two different things.
if types.Identical(obj.Type(), shadowed.Type()) {
f.Badf(ident.Pos(), "declaration of %s shadows declaration at %s", obj.Name(), f.loc(shadowed.Pos()))
}
}
// findVisibleErrs returns a mapping from each package-level variable of type "error" to nil.
func findVisibleErrs(prog *ssa.Program, qpos *QueryPos) map[*ssa.Global]ssa.Value {
globals := make(map[*ssa.Global]ssa.Value)
for _, pkg := range prog.AllPackages() {
for _, mem := range pkg.Members {
gbl, ok := mem.(*ssa.Global)
if !ok {
continue
}
gbltype := gbl.Type()
// globals are always pointers
if !types.Identical(deref(gbltype), builtinErrorType) {
continue
}
if !isAccessibleFrom(gbl.Object(), qpos.info.Pkg) {
continue
}
globals[gbl] = nil
}
}
return globals
}
// emitCompare emits to f code compute the boolean result of
// comparison comparison 'x op y'.
//
func emitCompare(f *Function, op token.Token, x, y Value, pos token.Pos) Value {
xt := x.Type().Underlying()
yt := y.Type().Underlying()
// Special case to optimise a tagless SwitchStmt so that
// these are equivalent
// switch { case e: ...}
// switch true { case e: ... }
// if e==true { ... }
// even in the case when e's type is an interface.
// TODO(adonovan): opt: generalise to x==true, false!=y, etc.
if x == vTrue && op == token.EQL {
if yt, ok := yt.(*types.Basic); ok && yt.Info()&types.IsBoolean != 0 {
return y
}
}
if types.Identical(xt, yt) {
// no conversion necessary
} else if _, ok := xt.(*types.Interface); ok {
y = emitConv(f, y, x.Type())
} else if _, ok := yt.(*types.Interface); ok {
x = emitConv(f, x, y.Type())
} else if _, ok := x.(*Const); ok {
x = emitConv(f, x, y.Type())
} else if _, ok := y.(*Const); ok {
y = emitConv(f, y, x.Type())
} else {
// other cases, e.g. channels. No-op.
}
v := &BinOp{
Op: op,
X: x,
Y: y,
}
v.setPos(pos)
v.setType(tBool)
return f.emit(v)
}
func checkUnusedResult(f *File, n ast.Node) {
call, ok := unparen(n.(*ast.ExprStmt).X).(*ast.CallExpr)
if !ok {
return // not a call statement
}
fun := unparen(call.Fun)
if f.pkg.types[fun].IsType() {
return // a conversion, not a call
}
selector, ok := fun.(*ast.SelectorExpr)
if !ok {
return // neither a method call nor a qualified ident
}
sel, ok := f.pkg.selectors[selector]
if ok && sel.Kind() == types.MethodVal {
// method (e.g. foo.String())
obj := sel.Obj().(*types.Func)
sig := sel.Type().(*types.Signature)
if types.Identical(sig, sigNoArgsStringResult) {
if unusedStringMethods[obj.Name()] {
f.Badf(call.Lparen, "result of (%s).%s call not used",
sig.Recv().Type(), obj.Name())
}
}
} else if !ok {
// package-qualified function (e.g. fmt.Errorf)
obj, _ := f.pkg.uses[selector.Sel]
if obj, ok := obj.(*types.Func); ok {
qname := obj.Pkg().Path() + "." + obj.Name()
if unusedFuncs[qname] {
f.Badf(call.Lparen, "result of %v call not used", qname)
}
}
}
}
func checkVarValue(t *testing.T, prog *ssa.Program, pkg *ssa.Package, ref []ast.Node, obj *types.Var, expKind string, wantAddr bool) {
// The prefix of all assertions messages.
prefix := fmt.Sprintf("VarValue(%s @ L%d)",
obj, prog.Fset.Position(ref[0].Pos()).Line)
v, gotAddr := prog.VarValue(obj, pkg, ref)
// Kind is the concrete type of the ssa Value.
gotKind := "nil"
if v != nil {
gotKind = fmt.Sprintf("%T", v)[len("*ssa."):]
}
// fmt.Printf("%s = %v (kind %q; expect %q) wantAddr=%t gotAddr=%t\n", prefix, v, gotKind, expKind, wantAddr, gotAddr) // debugging
// Check the kinds match.
// "nil" indicates expected failure (e.g. optimized away).
if expKind != gotKind {
t.Errorf("%s concrete type == %s, want %s", prefix, gotKind, expKind)
}
// Check the types match.
// If wantAddr, the expected type is the object's address.
if v != nil {
expType := obj.Type()
if wantAddr {
expType = types.NewPointer(expType)
if !gotAddr {
t.Errorf("%s: got value, want address", prefix)
}
} else if gotAddr {
t.Errorf("%s: got address, want value", prefix)
}
if !types.Identical(v.Type(), expType) {
t.Errorf("%s.Type() == %s, want %s", prefix, v.Type(), expType)
}
}
}
// matchType reports whether the two type ASTs denote identical types.
func (tr *Transformer) matchType(x, y ast.Expr) bool {
tx := tr.info.Types[x].Type
ty := tr.info.Types[y].Type
return types.Identical(tx, ty)
}
// lintVarDecls examines variable declarations. It complains about declarations with
// redundant LHS types that can be inferred from the RHS.
func (f *file) lintVarDecls() {
var lastGen *ast.GenDecl // last GenDecl entered.
f.walk(func(node ast.Node) bool {
switch v := node.(type) {
case *ast.GenDecl:
if v.Tok != token.CONST && v.Tok != token.VAR {
return false
}
lastGen = v
return true
case *ast.ValueSpec:
if lastGen.Tok == token.CONST {
return false
}
if len(v.Names) > 1 || v.Type == nil || len(v.Values) == 0 {
return false
}
rhs := v.Values[0]
// An underscore var appears in a common idiom for compile-time interface satisfaction,
// as in "var _ Interface = (*Concrete)(nil)".
if isIdent(v.Names[0], "_") {
return false
}
// If the RHS is a zero value, suggest dropping it.
zero := false
if lit, ok := rhs.(*ast.BasicLit); ok {
zero = zeroLiteral[lit.Value]
} else if isIdent(rhs, "nil") {
zero = true
}
if zero {
f.errorf(rhs, 0.9, category("zero-value"), "should drop = %s from declaration of var %s; it is the zero value", f.render(rhs), v.Names[0])
return false
}
lhsTyp := f.pkg.typeOf(v.Type)
rhsTyp := f.pkg.typeOf(rhs)
if lhsTyp != nil && rhsTyp != nil && !types.Identical(lhsTyp, rhsTyp) {
// Assignment to a different type is not redundant.
return false
}
// The next three conditions are for suppressing the warning in situations
// where we were unable to typecheck.
// If the LHS type is an interface, don't warn, since it is probably a
// concrete type on the RHS. Note that our feeble lexical check here
// will only pick up interface{} and other literal interface types;
// that covers most of the cases we care to exclude right now.
if _, ok := v.Type.(*ast.InterfaceType); ok {
return false
}
// If the RHS is an untyped const, only warn if the LHS type is its default type.
if defType, ok := f.isUntypedConst(rhs); ok && !isIdent(v.Type, defType) {
return false
}
// If the LHS is a known weaker type, and we couldn't type check both sides,
// don't warn.
if lhsTyp == nil || rhsTyp == nil {
if knownWeakerTypes[f.render(v.Type)] {
return false
}
}
f.errorf(v.Type, 0.8, category("type-inference"), "should omit type %s from declaration of var %s; it will be inferred from the right-hand side", f.render(v.Type), v.Names[0])
return false
}
return true
})
}
func (x rtype) eq(_ types.Type, y interface{}) bool {
return types.Identical(x.t, y.(rtype).t)
}
// nil-tolerant variant of types.Identical.
func sameType(x, y types.Type) bool {
if x == nil {
return y == nil
}
return y != nil && types.Identical(x, y)
}
func (c *funcContext) translateStmt(stmt ast.Stmt, label *types.Label) {
c.SetPos(stmt.Pos())
stmt = filter.IncDecStmt(stmt, c.p.Info)
stmt = filter.Assign(stmt, c.p.Info)
switch s := stmt.(type) {
case *ast.BlockStmt:
c.translateStmtList(s.List)
case *ast.IfStmt:
if s.Init != nil {
c.translateStmt(s.Init, nil)
}
var caseClauses []ast.Stmt
ifStmt := s
for {
caseClauses = append(caseClauses, &ast.CaseClause{List: []ast.Expr{ifStmt.Cond}, Body: ifStmt.Body.List})
switch elseStmt := ifStmt.Else.(type) {
case *ast.IfStmt:
if elseStmt.Init != nil {
caseClauses = append(caseClauses, &ast.CaseClause{List: nil, Body: []ast.Stmt{elseStmt}})
break
}
ifStmt = elseStmt
continue
case *ast.BlockStmt:
caseClauses = append(caseClauses, &ast.CaseClause{List: nil, Body: elseStmt.List})
case *ast.EmptyStmt, nil:
// no else clause
default:
panic(fmt.Sprintf("Unhandled else: %T\n", elseStmt))
}
break
}
c.translateBranchingStmt(caseClauses, false, nil, nil, nil, c.Flattened[s])
case *ast.SwitchStmt:
if s.Init != nil {
c.translateStmt(s.Init, nil)
}
tag := s.Tag
if tag == nil {
tag = ast.NewIdent("true")
c.p.Types[tag] = types.TypeAndValue{Type: types.Typ[types.Bool], Value: exact.MakeBool(true)}
}
if c.p.Types[tag].Value == nil {
refVar := c.newVariable("_ref")
c.Printf("%s = %s;", refVar, c.translateExpr(tag))
tag = c.newIdent(refVar, c.p.Types[tag].Type)
}
translateCond := func(cond ast.Expr) *expression {
return c.translateExpr(&ast.BinaryExpr{
X: tag,
Op: token.EQL,
Y: cond,
})
}
c.translateBranchingStmt(s.Body.List, true, translateCond, nil, label, c.Flattened[s])
case *ast.TypeSwitchStmt:
if s.Init != nil {
c.translateStmt(s.Init, nil)
}
refVar := c.newVariable("_ref")
var expr ast.Expr
var printCaseBodyPrefix func(index int)
switch a := s.Assign.(type) {
case *ast.AssignStmt:
expr = a.Rhs[0].(*ast.TypeAssertExpr).X
printCaseBodyPrefix = func(index int) {
value := refVar
caseClause := s.Body.List[index].(*ast.CaseClause)
if len(caseClause.List) == 1 {
t := c.p.Types[caseClause.List[0]].Type
if _, isInterface := t.Underlying().(*types.Interface); !isInterface && !types.Identical(t, types.Typ[types.UntypedNil]) {
value += ".$val"
}
}
c.Printf("%s = %s;", c.objectName(c.p.Implicits[caseClause]), value)
}
case *ast.ExprStmt:
expr = a.X.(*ast.TypeAssertExpr).X
}
c.Printf("%s = %s;", refVar, c.translateExpr(expr))
translateCond := func(cond ast.Expr) *expression {
if types.Identical(c.p.Types[cond].Type, types.Typ[types.UntypedNil]) {
return c.formatExpr("%s === $ifaceNil", refVar)
}
return c.formatExpr("$assertType(%s, %s, true)[1]", refVar, c.typeName(c.p.Types[cond].Type))
}
c.translateBranchingStmt(s.Body.List, true, translateCond, printCaseBodyPrefix, label, c.Flattened[s])
case *ast.ForStmt:
if s.Init != nil {
c.translateStmt(s.Init, nil)
}
cond := func() string {
if s.Cond == nil {
return "true"
}
return c.translateExpr(s.Cond).String()
}
c.translateLoopingStmt(cond, s.Body, nil, func() {
if s.Post != nil {
c.translateStmt(s.Post, nil)
}
}, label, c.Flattened[s])
case *ast.RangeStmt:
refVar := c.newVariable("_ref")
c.Printf("%s = %s;", refVar, c.translateExpr(s.X))
switch t := c.p.Types[s.X].Type.Underlying().(type) {
case *types.Basic:
iVar := c.newVariable("_i")
c.Printf("%s = 0;", iVar)
runeVar := c.newVariable("_rune")
c.translateLoopingStmt(func() string { return iVar + " < " + refVar + ".length" }, s.Body, func() {
c.Printf("%s = $decodeRune(%s, %s);", runeVar, refVar, iVar)
if !isBlank(s.Key) {
c.Printf("%s", c.translateAssign(s.Key, iVar, types.Typ[types.Int], s.Tok == token.DEFINE))
}
if !isBlank(s.Value) {
c.Printf("%s", c.translateAssign(s.Value, runeVar+"[0]", types.Typ[types.Rune], s.Tok == token.DEFINE))
}
}, func() {
c.Printf("%s += %s[1];", iVar, runeVar)
}, label, c.Flattened[s])
case *types.Map:
iVar := c.newVariable("_i")
c.Printf("%s = 0;", iVar)
keysVar := c.newVariable("_keys")
c.Printf("%s = $keys(%s);", keysVar, refVar)
c.translateLoopingStmt(func() string { return iVar + " < " + keysVar + ".length" }, s.Body, func() {
entryVar := c.newVariable("_entry")
c.Printf("%s = %s[%s[%s]];", entryVar, refVar, keysVar, iVar)
c.translateStmt(&ast.IfStmt{
Cond: c.newIdent(entryVar+" === undefined", types.Typ[types.Bool]),
Body: &ast.BlockStmt{List: []ast.Stmt{&ast.BranchStmt{Tok: token.CONTINUE}}},
}, nil)
if !isBlank(s.Key) {
c.Printf("%s", c.translateAssign(s.Key, entryVar+".k", t.Key(), s.Tok == token.DEFINE))
}
if !isBlank(s.Value) {
c.Printf("%s", c.translateAssign(s.Value, entryVar+".v", t.Elem(), s.Tok == token.DEFINE))
}
}, func() {
c.Printf("%s++;", iVar)
}, label, c.Flattened[s])
case *types.Array, *types.Pointer, *types.Slice:
var length string
var elemType types.Type
switch t2 := t.(type) {
case *types.Array:
length = fmt.Sprintf("%d", t2.Len())
elemType = t2.Elem()
case *types.Pointer:
length = fmt.Sprintf("%d", t2.Elem().Underlying().(*types.Array).Len())
elemType = t2.Elem().Underlying().(*types.Array).Elem()
case *types.Slice:
length = refVar + ".$length"
elemType = t2.Elem()
}
iVar := c.newVariable("_i")
c.Printf("%s = 0;", iVar)
c.translateLoopingStmt(func() string { return iVar + " < " + length }, s.Body, func() {
if !isBlank(s.Key) {
c.Printf("%s", c.translateAssign(s.Key, iVar, types.Typ[types.Int], s.Tok == token.DEFINE))
}
if !isBlank(s.Value) {
c.Printf("%s", c.translateAssign(s.Value, c.translateImplicitConversion(c.setType(&ast.IndexExpr{
X: c.newIdent(refVar, t),
Index: c.newIdent(iVar, types.Typ[types.Int]),
}, elemType), elemType).String(), elemType, s.Tok == token.DEFINE))
}
}, func() {
c.Printf("%s++;", iVar)
}, label, c.Flattened[s])
case *types.Chan:
okVar := c.newIdent(c.newVariable("_ok"), types.Typ[types.Bool])
key := s.Key
tok := s.Tok
if key == nil {
key = ast.NewIdent("_")
tok = token.ASSIGN
}
forStmt := &ast.ForStmt{
Body: &ast.BlockStmt{
List: []ast.Stmt{
&ast.AssignStmt{
Lhs: []ast.Expr{
key,
okVar,
},
Rhs: []ast.Expr{
c.setType(&ast.UnaryExpr{X: c.newIdent(refVar, t), Op: token.ARROW}, types.NewTuple(types.NewVar(0, nil, "", t.Elem()), types.NewVar(0, nil, "", types.Typ[types.Bool]))),
},
Tok: tok,
},
&ast.IfStmt{
Cond: &ast.UnaryExpr{X: okVar, Op: token.NOT},
Body: &ast.BlockStmt{List: []ast.Stmt{&ast.BranchStmt{Tok: token.BREAK}}},
},
s.Body,
},
},
}
c.Flattened[forStmt] = true
c.translateStmt(forStmt, label)
default:
panic("")
}
case *ast.BranchStmt:
normalLabel := ""
blockingLabel := ""
data := c.flowDatas[nil]
if s.Label != nil {
normalLabel = " " + s.Label.Name
blockingLabel = " s" // use explicit label "s", because surrounding loop may not be flattened
data = c.flowDatas[c.p.Uses[s.Label].(*types.Label)]
}
switch s.Tok {
case token.BREAK:
c.PrintCond(data.endCase == 0, fmt.Sprintf("break%s;", normalLabel), fmt.Sprintf("$s = %d; continue%s;", data.endCase, blockingLabel))
case token.CONTINUE:
data.postStmt()
c.PrintCond(data.beginCase == 0, fmt.Sprintf("continue%s;", normalLabel), fmt.Sprintf("$s = %d; continue%s;", data.beginCase, blockingLabel))
case token.GOTO:
c.PrintCond(false, "goto "+s.Label.Name, fmt.Sprintf("$s = %d; continue;", c.labelCase(c.p.Uses[s.Label].(*types.Label))))
case token.FALLTHROUGH:
// handled in CaseClause
default:
panic("Unhandled branch statment: " + s.Tok.String())
}
case *ast.ReturnStmt:
results := s.Results
if c.resultNames != nil {
if len(s.Results) != 0 {
c.translateStmt(&ast.AssignStmt{
Lhs: c.resultNames,
Tok: token.ASSIGN,
Rhs: s.Results,
}, nil)
}
results = c.resultNames
}
c.Printf("return%s;", c.translateResults(results))
case *ast.DeferStmt:
isBuiltin := false
isJs := false
switch fun := s.Call.Fun.(type) {
case *ast.Ident:
var builtin *types.Builtin
builtin, isBuiltin = c.p.Uses[fun].(*types.Builtin)
if isBuiltin && builtin.Name() == "recover" {
c.Printf("$deferred.push([$recover, []]);")
return
}
case *ast.SelectorExpr:
isJs = typesutil.IsJsPackage(c.p.Uses[fun.Sel].Pkg())
}
sig := c.p.Types[s.Call.Fun].Type.Underlying().(*types.Signature)
args := c.translateArgs(sig, s.Call.Args, s.Call.Ellipsis.IsValid(), true)
if isBuiltin || isJs {
vars := make([]string, len(s.Call.Args))
callArgs := make([]ast.Expr, len(s.Call.Args))
for i, arg := range s.Call.Args {
v := c.newVariable("_arg")
vars[i] = v
callArgs[i] = c.newIdent(v, c.p.Types[arg].Type)
}
call := c.translateExpr(&ast.CallExpr{
Fun: s.Call.Fun,
Args: callArgs,
Ellipsis: s.Call.Ellipsis,
})
c.Printf("$deferred.push([function(%s) { %s; }, [%s]]);", strings.Join(vars, ", "), call, strings.Join(args, ", "))
return
}
c.Printf("$deferred.push([%s, [%s]]);", c.translateExpr(s.Call.Fun), strings.Join(args, ", "))
case *ast.AssignStmt:
if s.Tok != token.ASSIGN && s.Tok != token.DEFINE {
panic(s.Tok)
}
if s.Tok == token.DEFINE {
for _, lhs := range s.Lhs {
if !isBlank(lhs) {
obj := c.p.Defs[lhs.(*ast.Ident)]
if obj == nil {
obj = c.p.Uses[lhs.(*ast.Ident)]
}
c.setType(lhs, obj.Type())
}
}
}
switch {
case len(s.Lhs) == 1 && len(s.Rhs) == 1:
lhs := astutil.RemoveParens(s.Lhs[0])
if isBlank(lhs) {
if analysis.HasSideEffect(s.Rhs[0], c.p.Info.Info) {
c.Printf("%s;", c.translateExpr(s.Rhs[0]).String())
}
return
}
lhsType := c.p.Types[s.Lhs[0]].Type
c.Printf("%s", c.translateAssignOfExpr(lhs, s.Rhs[0], lhsType, s.Tok == token.DEFINE))
case len(s.Lhs) > 1 && len(s.Rhs) == 1:
tupleVar := c.newVariable("_tuple")
out := tupleVar + " = " + c.translateExpr(s.Rhs[0]).String() + ";"
tuple := c.p.Types[s.Rhs[0]].Type.(*types.Tuple)
for i, lhs := range s.Lhs {
lhs = astutil.RemoveParens(lhs)
if !isBlank(lhs) {
lhsType := c.p.Types[s.Lhs[i]].Type
out += " " + c.translateAssignOfExpr(lhs, c.newIdent(fmt.Sprintf("%s[%d]", tupleVar, i), tuple.At(i).Type()), lhsType, s.Tok == token.DEFINE)
}
}
c.Printf("%s", out)
case len(s.Lhs) == len(s.Rhs):
tmpVars := make([]string, len(s.Rhs))
var parts []string
for i, rhs := range s.Rhs {
tmpVars[i] = c.newVariable("_tmp")
if isBlank(astutil.RemoveParens(s.Lhs[i])) {
if analysis.HasSideEffect(rhs, c.p.Info.Info) {
c.Printf("%s;", c.translateExpr(rhs).String())
}
continue
}
lhsType := c.p.Types[s.Lhs[i]].Type
parts = append(parts, c.translateAssignOfExpr(c.newIdent(tmpVars[i], c.p.Types[s.Lhs[i]].Type), rhs, lhsType, true))
}
for i, lhs := range s.Lhs {
lhs = astutil.RemoveParens(lhs)
if !isBlank(lhs) {
t := c.p.Types[lhs].Type
parts = append(parts, c.translateAssignOfExpr(lhs, c.newIdent(tmpVars[i], t), t, s.Tok == token.DEFINE))
}
}
c.Printf("%s", strings.Join(parts, " "))
default:
panic("Invalid arity of AssignStmt.")
}
case *ast.DeclStmt:
decl := s.Decl.(*ast.GenDecl)
switch decl.Tok {
case token.VAR:
for _, spec := range s.Decl.(*ast.GenDecl).Specs {
valueSpec := spec.(*ast.ValueSpec)
lhs := make([]ast.Expr, len(valueSpec.Names))
for i, name := range valueSpec.Names {
lhs[i] = name
}
rhs := valueSpec.Values
isTuple := false
if len(rhs) == 1 {
_, isTuple = c.p.Types[rhs[0]].Type.(*types.Tuple)
}
for len(rhs) < len(lhs) && !isTuple {
rhs = append(rhs, nil)
}
c.translateStmt(&ast.AssignStmt{
Lhs: lhs,
Tok: token.DEFINE,
Rhs: rhs,
}, nil)
}
case token.TYPE:
for _, spec := range decl.Specs {
o := c.p.Defs[spec.(*ast.TypeSpec).Name].(*types.TypeName)
c.p.typeNames = append(c.p.typeNames, o)
c.p.objectNames[o] = c.newVariableWithLevel(o.Name(), true)
c.p.dependencies[o] = true
}
case token.CONST:
// skip, constants are inlined
}
case *ast.ExprStmt:
expr := c.translateExpr(s.X)
if expr != nil && expr.String() != "" {
c.Printf("%s;", expr)
}
case *ast.LabeledStmt:
label := c.p.Defs[s.Label].(*types.Label)
if c.GotoLabel[label] {
c.PrintCond(false, s.Label.Name+":", fmt.Sprintf("case %d:", c.labelCase(label)))
}
c.translateStmt(s.Stmt, label)
case *ast.GoStmt:
c.Printf("$go(%s, [%s]);", c.translateExpr(s.Call.Fun), strings.Join(c.translateArgs(c.p.Types[s.Call.Fun].Type.Underlying().(*types.Signature), s.Call.Args, s.Call.Ellipsis.IsValid(), false), ", "))
case *ast.SendStmt:
chanType := c.p.Types[s.Chan].Type.Underlying().(*types.Chan)
call := &ast.CallExpr{
Fun: c.newIdent("$send", types.NewSignature(nil, types.NewTuple(types.NewVar(0, nil, "", chanType), types.NewVar(0, nil, "", chanType.Elem())), nil, false)),
Args: []ast.Expr{s.Chan, s.Value},
}
c.Blocking[call] = true
c.translateStmt(&ast.ExprStmt{X: call}, label)
case *ast.SelectStmt:
var channels []string
var caseClauses []ast.Stmt
flattened := false
hasDefault := false
for i, s := range s.Body.List {
clause := s.(*ast.CommClause)
switch comm := clause.Comm.(type) {
case nil:
channels = append(channels, "[]")
hasDefault = true
case *ast.ExprStmt:
channels = append(channels, c.formatExpr("[%e]", astutil.RemoveParens(comm.X).(*ast.UnaryExpr).X).String())
case *ast.AssignStmt:
channels = append(channels, c.formatExpr("[%e]", astutil.RemoveParens(comm.Rhs[0]).(*ast.UnaryExpr).X).String())
case *ast.SendStmt:
channels = append(channels, c.formatExpr("[%e, %e]", comm.Chan, comm.Value).String())
default:
panic(fmt.Sprintf("unhandled: %T", comm))
}
indexLit := &ast.BasicLit{Kind: token.INT}
c.p.Types[indexLit] = types.TypeAndValue{Type: types.Typ[types.Int], Value: exact.MakeInt64(int64(i))}
caseClauses = append(caseClauses, &ast.CaseClause{
List: []ast.Expr{indexLit},
Body: clause.Body,
})
flattened = flattened || c.Flattened[clause]
}
selectCall := c.setType(&ast.CallExpr{
Fun: c.newIdent("$select", types.NewSignature(nil, types.NewTuple(types.NewVar(0, nil, "", types.NewInterface(nil, nil))), types.NewTuple(types.NewVar(0, nil, "", types.Typ[types.Int])), false)),
Args: []ast.Expr{c.newIdent(fmt.Sprintf("[%s]", strings.Join(channels, ", ")), types.NewInterface(nil, nil))},
}, types.Typ[types.Int])
c.Blocking[selectCall] = !hasDefault
selectionVar := c.newVariable("_selection")
c.Printf("%s = %s;", selectionVar, c.translateExpr(selectCall))
translateCond := func(cond ast.Expr) *expression {
return c.formatExpr("%s[0] === %e", selectionVar, cond)
}
printCaseBodyPrefix := func(index int) {
if assign, ok := s.Body.List[index].(*ast.CommClause).Comm.(*ast.AssignStmt); ok {
switch rhsType := c.p.Types[assign.Rhs[0]].Type.(type) {
case *types.Tuple:
c.translateStmt(&ast.AssignStmt{Lhs: assign.Lhs, Rhs: []ast.Expr{c.newIdent(selectionVar+"[1]", rhsType)}, Tok: assign.Tok}, nil)
default:
c.translateStmt(&ast.AssignStmt{Lhs: assign.Lhs, Rhs: []ast.Expr{c.newIdent(selectionVar+"[1][0]", rhsType)}, Tok: assign.Tok}, nil)
}
}
}
c.translateBranchingStmt(caseClauses, true, translateCond, printCaseBodyPrefix, label, flattened)
case *ast.EmptyStmt:
// skip
default:
panic(fmt.Sprintf("Unhandled statement: %T\n", s))
}
}
// Like isTest, but checks the signature too.
func isTestSig(f *Function, prefix string, sig *types.Signature) bool {
return isTest(f.Name(), prefix) && types.Identical(f.Signature, sig)
}
// emitConv emits to f code to convert Value val to exactly type typ,
// and returns the converted value. Implicit conversions are required
// by language assignability rules in assignments, parameter passing,
// etc. Conversions cannot fail dynamically.
//
func emitConv(f *Function, val Value, typ types.Type) Value {
t_src := val.Type()
// Identical types? Conversion is a no-op.
if types.Identical(t_src, typ) {
return val
}
ut_dst := typ.Underlying()
ut_src := t_src.Underlying()
// Just a change of type, but not value or representation?
if isValuePreserving(ut_src, ut_dst) {
c := &ChangeType{X: val}
c.setType(typ)
return f.emit(c)
}
// Conversion to, or construction of a value of, an interface type?
if _, ok := ut_dst.(*types.Interface); ok {
// Assignment from one interface type to another?
if _, ok := ut_src.(*types.Interface); ok {
c := &ChangeInterface{X: val}
c.setType(typ)
return f.emit(c)
}
// Untyped nil constant? Return interface-typed nil constant.
if ut_src == tUntypedNil {
return nilConst(typ)
}
// Convert (non-nil) "untyped" literals to their default type.
if t, ok := ut_src.(*types.Basic); ok && t.Info()&types.IsUntyped != 0 {
val = emitConv(f, val, DefaultType(ut_src))
}
f.Pkg.needMethodsOf(val.Type())
mi := &MakeInterface{X: val}
mi.setType(typ)
return f.emit(mi)
}
// Conversion of a compile-time constant value?
if c, ok := val.(*Const); ok {
if _, ok := ut_dst.(*types.Basic); ok || c.IsNil() {
// Conversion of a compile-time constant to
// another constant type results in a new
// constant of the destination type and
// (initially) the same abstract value.
// We don't truncate the value yet.
return NewConst(c.Value, typ)
}
// We're converting from constant to non-constant type,
// e.g. string -> []byte/[]rune.
}
// A representation-changing conversion?
// At least one of {ut_src,ut_dst} must be *Basic.
// (The other may be []byte or []rune.)
_, ok1 := ut_src.(*types.Basic)
_, ok2 := ut_dst.(*types.Basic)
if ok1 || ok2 {
c := &Convert{X: val}
c.setType(typ)
return f.emit(c)
}
panic(fmt.Sprintf("in %s: cannot convert %s (%s) to %s", f, val, val.Type(), typ))
}
func (c *funcContext) translateBuiltin(name string, sig *types.Signature, args []ast.Expr, ellipsis bool) *expression {
switch name {
case "new":
t := sig.Results().At(0).Type().(*types.Pointer)
if c.p.Pkg.Path() == "syscall" && types.Identical(t.Elem().Underlying(), types.Typ[types.Uintptr]) {
return c.formatExpr("new Uint8Array(8)")
}
switch t.Elem().Underlying().(type) {
case *types.Struct, *types.Array:
return c.formatExpr("%e", c.zeroValue(t.Elem()))
default:
return c.formatExpr("$newDataPointer(%e, %s)", c.zeroValue(t.Elem()), c.typeName(t))
}
case "make":
switch argType := c.p.TypeOf(args[0]).Underlying().(type) {
case *types.Slice:
t := c.typeName(c.p.TypeOf(args[0]))
if len(args) == 3 {
return c.formatExpr("$makeSlice(%s, %f, %f)", t, args[1], args[2])
}
return c.formatExpr("$makeSlice(%s, %f)", t, args[1])
case *types.Map:
return c.formatExpr("{}")
case *types.Chan:
length := "0"
if len(args) == 2 {
length = c.translateExpr(args[1]).String()
}
return c.formatExpr("new %s(%s)", c.typeName(c.p.TypeOf(args[0])), length)
default:
panic(fmt.Sprintf("Unhandled make type: %T\n", argType))
}
case "len":
switch argType := c.p.TypeOf(args[0]).Underlying().(type) {
case *types.Basic:
return c.formatExpr("%e.length", args[0])
case *types.Slice:
return c.formatExpr("%e.$length", args[0])
case *types.Pointer:
return c.formatExpr("(%e, %d)", args[0], argType.Elem().(*types.Array).Len())
case *types.Map:
return c.formatExpr("$keys(%e).length", args[0])
case *types.Chan:
return c.formatExpr("%e.$buffer.length", args[0])
// length of array is constant
default:
panic(fmt.Sprintf("Unhandled len type: %T\n", argType))
}
case "cap":
switch argType := c.p.TypeOf(args[0]).Underlying().(type) {
case *types.Slice, *types.Chan:
return c.formatExpr("%e.$capacity", args[0])
case *types.Pointer:
return c.formatExpr("(%e, %d)", args[0], argType.Elem().(*types.Array).Len())
// capacity of array is constant
default:
panic(fmt.Sprintf("Unhandled cap type: %T\n", argType))
}
case "panic":
return c.formatExpr("$panic(%s)", c.translateImplicitConversion(args[0], types.NewInterface(nil, nil)))
case "append":
if ellipsis || len(args) == 1 {
argStr := c.translateArgs(sig, args, ellipsis, false)
return c.formatExpr("$appendSlice(%s, %s)", argStr[0], argStr[1])
}
sliceType := sig.Results().At(0).Type().Underlying().(*types.Slice)
return c.formatExpr("$append(%e, %s)", args[0], strings.Join(c.translateExprSlice(args[1:], sliceType.Elem()), ", "))
case "delete":
keyType := c.p.TypeOf(args[0]).Underlying().(*types.Map).Key()
return c.formatExpr(`delete %e[%s.keyFor(%s)]`, args[0], c.typeName(keyType), c.translateImplicitConversion(args[1], keyType))
case "copy":
if basic, isBasic := c.p.TypeOf(args[1]).Underlying().(*types.Basic); isBasic && isString(basic) {
return c.formatExpr("$copyString(%e, %e)", args[0], args[1])
}
return c.formatExpr("$copySlice(%e, %e)", args[0], args[1])
case "print", "println":
return c.formatExpr("console.log(%s)", strings.Join(c.translateExprSlice(args, nil), ", "))
case "complex":
argStr := c.translateArgs(sig, args, ellipsis, false)
return c.formatExpr("new %s(%s, %s)", c.typeName(sig.Results().At(0).Type()), argStr[0], argStr[1])
case "real":
return c.formatExpr("%e.$real", args[0])
case "imag":
return c.formatExpr("%e.$imag", args[0])
case "recover":
return c.formatExpr("$recover()")
case "close":
return c.formatExpr(`$close(%e)`, args[0])
default:
panic(fmt.Sprintf("Unhandled builtin: %s\n", name))
}
}
func (c *funcContext) translateConversion(expr ast.Expr, desiredType types.Type) *expression {
exprType := c.p.TypeOf(expr)
if types.Identical(exprType, desiredType) {
return c.translateExpr(expr)
}
if c.p.Pkg.Path() == "reflect" {
if call, isCall := expr.(*ast.CallExpr); isCall && types.Identical(c.p.TypeOf(call.Fun), types.Typ[types.UnsafePointer]) {
if ptr, isPtr := desiredType.(*types.Pointer); isPtr {
if named, isNamed := ptr.Elem().(*types.Named); isNamed {
switch named.Obj().Name() {
case "arrayType", "chanType", "funcType", "interfaceType", "mapType", "ptrType", "sliceType", "structType":
return c.formatExpr("%e.kindType", call.Args[0]) // unsafe conversion
default:
return c.translateExpr(expr)
}
}
}
}
}
switch t := desiredType.Underlying().(type) {
case *types.Basic:
switch {
case isInteger(t):
basicExprType := exprType.Underlying().(*types.Basic)
switch {
case is64Bit(t):
if !is64Bit(basicExprType) {
if basicExprType.Kind() == types.Uintptr { // this might be an Object returned from reflect.Value.Pointer()
return c.formatExpr("new %1s(0, %2e.constructor === Number ? %2e : 1)", c.typeName(desiredType), expr)
}
return c.formatExpr("new %s(0, %e)", c.typeName(desiredType), expr)
}
return c.formatExpr("new %1s(%2h, %2l)", c.typeName(desiredType), expr)
case is64Bit(basicExprType):
if !isUnsigned(t) && !isUnsigned(basicExprType) {
return c.fixNumber(c.formatParenExpr("%1l + ((%1h >> 31) * 4294967296)", expr), t)
}
return c.fixNumber(c.formatExpr("%s.$low", c.translateExpr(expr)), t)
case isFloat(basicExprType):
return c.formatParenExpr("%e >> 0", expr)
case types.Identical(exprType, types.Typ[types.UnsafePointer]):
return c.translateExpr(expr)
default:
return c.fixNumber(c.translateExpr(expr), t)
}
case isFloat(t):
if t.Kind() == types.Float32 && exprType.Underlying().(*types.Basic).Kind() == types.Float64 {
return c.formatExpr("$fround(%e)", expr)
}
return c.formatExpr("%f", expr)
case isComplex(t):
return c.formatExpr("new %1s(%2r, %2i)", c.typeName(desiredType), expr)
case isString(t):
value := c.translateExpr(expr)
switch et := exprType.Underlying().(type) {
case *types.Basic:
if is64Bit(et) {
value = c.formatExpr("%s.$low", value)
}
if isNumeric(et) {
return c.formatExpr("$encodeRune(%s)", value)
}
return value
case *types.Slice:
if types.Identical(et.Elem().Underlying(), types.Typ[types.Rune]) {
return c.formatExpr("$runesToString(%s)", value)
}
return c.formatExpr("$bytesToString(%s)", value)
default:
panic(fmt.Sprintf("Unhandled conversion: %v\n", et))
}
case t.Kind() == types.UnsafePointer:
if unary, isUnary := expr.(*ast.UnaryExpr); isUnary && unary.Op == token.AND {
if indexExpr, isIndexExpr := unary.X.(*ast.IndexExpr); isIndexExpr {
return c.formatExpr("$sliceToArray(%s)", c.translateConversionToSlice(indexExpr.X, types.NewSlice(types.Typ[types.Uint8])))
}
if ident, isIdent := unary.X.(*ast.Ident); isIdent && ident.Name == "_zero" {
return c.formatExpr("new Uint8Array(0)")
}
}
if ptr, isPtr := c.p.TypeOf(expr).(*types.Pointer); c.p.Pkg.Path() == "syscall" && isPtr {
if s, isStruct := ptr.Elem().Underlying().(*types.Struct); isStruct {
array := c.newVariable("_array")
target := c.newVariable("_struct")
c.Printf("%s = new Uint8Array(%d);", array, sizes32.Sizeof(s))
c.Delayed(func() {
c.Printf("%s = %s, %s;", target, c.translateExpr(expr), c.loadStruct(array, target, s))
})
return c.formatExpr("%s", array)
}
}
if call, ok := expr.(*ast.CallExpr); ok {
if id, ok := call.Fun.(*ast.Ident); ok && id.Name == "new" {
return c.formatExpr("new Uint8Array(%d)", int(sizes32.Sizeof(c.p.TypeOf(call.Args[0]))))
}
}
}
case *types.Slice:
switch et := exprType.Underlying().(type) {
case *types.Basic:
if isString(et) {
if types.Identical(t.Elem().Underlying(), types.Typ[types.Rune]) {
return c.formatExpr("new %s($stringToRunes(%e))", c.typeName(desiredType), expr)
}
return c.formatExpr("new %s($stringToBytes(%e))", c.typeName(desiredType), expr)
}
case *types.Array, *types.Pointer:
return c.formatExpr("new %s(%e)", c.typeName(desiredType), expr)
}
case *types.Pointer:
if s, isStruct := t.Elem().Underlying().(*types.Struct); isStruct {
if c.p.Pkg.Path() == "syscall" && types.Identical(exprType, types.Typ[types.UnsafePointer]) {
array := c.newVariable("_array")
target := c.newVariable("_struct")
return c.formatExpr("(%s = %e, %s = %e, %s, %s)", array, expr, target, c.zeroValue(t.Elem()), c.loadStruct(array, target, s), target)
}
return c.formatExpr("$pointerOfStructConversion(%e, %s)", expr, c.typeName(t))
}
if !types.Identical(exprType, types.Typ[types.UnsafePointer]) {
exprTypeElem := exprType.Underlying().(*types.Pointer).Elem()
ptrVar := c.newVariable("_ptr")
getterConv := c.translateConversion(c.setType(&ast.StarExpr{X: c.newIdent(ptrVar, exprType)}, exprTypeElem), t.Elem())
setterConv := c.translateConversion(c.newIdent("$v", t.Elem()), exprTypeElem)
return c.formatExpr("(%1s = %2e, new %3s(function() { return %4s; }, function($v) { %1s.$set(%5s); }, %1s.$target))", ptrVar, expr, c.typeName(desiredType), getterConv, setterConv)
}
case *types.Interface:
if types.Identical(exprType, types.Typ[types.UnsafePointer]) {
return c.translateExpr(expr)
}
}
return c.translateImplicitConversionWithCloning(expr, desiredType)
}