func (f *File) validParams(params *ast.FieldList) *Error {
if params == nil {
panic("ERROR: params fieldlist should never be nil")
}
if params.List == nil {
return nil
}
for i := 0; i < params.NumFields(); i++ {
field := params.List[i]
if field == nil {
return &Error{errors.New(fmt.Sprint("ERROR nil field, anonymous fields not allowed!!")), params.Pos()}
}
if len(field.Names) != 1 {
panic("ERROR len(field.Names) != 1!!")
}
name := field.Names[0]
if name == nil {
panic("ERROR name == nil, this shouldn't occur")
}
typ := f.Info.TypeOf(field.Type)
if e := f.validParamType(typ); e != nil {
e.Pos = field.Pos()
return e
}
}
return nil
}
// storeParams handles parameters
//
// If the parameters include an ellipsis we need to copy parameters into
// an interface{} array as follows.
//
// params := []interface{}{}
// params[0] = p1
// params[1] = p2
// for i, p := range ellipsisParam {
// params[2+i] = p
// }
//
// If not it is better to add the params to the call directly for performance
// reasons
func storeParams(params *ast.FieldList) ([]ast.Stmt, bool, error) {
// Is there an ellipsis parameter?
listlen := len(params.List)
if listlen > 0 {
last := params.List[len(params.List)-1]
if _, ok := last.Type.(*ast.Ellipsis); ok {
code := fmt.Sprintf("\tut__params := make([]interface{}, %d + len(%s))\n", params.NumFields()-1, last.Names[0].Name)
i := 0
for _, f := range params.List {
for _, n := range f.Names {
if _, ok := f.Type.(*ast.Ellipsis); ok {
// Ellipsis expression
code += fmt.Sprintf(`
for j, p := range %s {
ut__params[%d+j] = p
}
`, n.Name, i)
} else {
code += fmt.Sprintf("\tut__params[%d] = %s\n", i, n.Name)
}
i++
}
}
stmts, err := parseCodeBlock(code)
return stmts, true, err
}
}
return nil, false, nil
}
func (a *typeCompiler) compileFields(fields *ast.FieldList, allowRec bool) ([]Type, []*ast.Ident, []token.Pos, bool) {
n := fields.NumFields()
ts := make([]Type, n)
ns := make([]*ast.Ident, n)
ps := make([]token.Pos, n)
bad := false
if fields != nil {
i := 0
for _, f := range fields.List {
t := a.compileType(f.Type, allowRec)
if t == nil {
bad = true
}
if f.Names == nil {
ns[i] = nil
ts[i] = t
ps[i] = f.Type.Pos()
i++
continue
}
for _, n := range f.Names {
ns[i] = n
ts[i] = t
ps[i] = n.Pos()
i++
}
}
}
return ts, ns, ps, bad
}
func (check *Checker) collectParams(scope *Scope, list *ast.FieldList, variadicOk bool) (params []*Var, variadic bool) {
if list == nil {
return
}
var named, anonymous bool
for i, field := range list.List {
ftype := field.Type
if t, _ := ftype.(*ast.Ellipsis); t != nil {
ftype = t.Elt
if variadicOk && i == len(list.List)-1 {
variadic = true
} else {
check.invalidAST(field.Pos(), "... not permitted")
// ignore ... and continue
}
}
typ := check.typ(ftype)
// The parser ensures that f.Tag is nil and we don't
// care if a constructed AST contains a non-nil tag.
if len(field.Names) > 0 {
// named parameter
for _, name := range field.Names {
if name.Name == "" {
check.invalidAST(name.Pos(), "anonymous parameter")
// ok to continue
}
par := NewParam(name.Pos(), check.pkg, name.Name, typ)
check.declare(scope, name, par, scope.pos)
params = append(params, par)
}
named = true
} else {
// anonymous parameter
par := NewParam(ftype.Pos(), check.pkg, "", typ)
check.recordImplicit(field, par)
params = append(params, par)
anonymous = true
}
}
if named && anonymous {
check.invalidAST(list.Pos(), "list contains both named and anonymous parameters")
// ok to continue
}
// For a variadic function, change the last parameter's type from T to []T.
if variadic && len(params) > 0 {
last := params[len(params)-1]
last.typ = &Slice{elem: last.typ}
}
return
}
func (p *parser) parseParams(n *parse.Node, scope *ast.Scope) *ast.FieldList {
fieldList := ast.FieldList{
Opening: token.Pos(n.Child(0).Pos()),
Closing: token.Pos(n.LastChild().Pos()),
}
if n.Child(1).Is(parameterList) {
eachListItem(parameterDecl, n.Child(1), func(item *parse.Node) {
fieldList.List = append(fieldList.List, p.parseParamDecl(item, scope))
})
}
return &fieldList
}
// Sets multiLine to true if the signature spans multiple lines.
func (p *printer) signature(params, result *ast.FieldList, multiLine *bool) {
p.parameters(params, multiLine)
n := result.NumFields()
if n > 0 {
p.print(blank)
if n == 1 && result.List[0].Names == nil {
// single anonymous result; no ()'s
p.expr(result.List[0].Type, multiLine)
return
}
p.parameters(result, multiLine)
}
}
func (p *printer) funcreturn(result *ast.FieldList) {
n := result.NumFields()
if n > 0 {
p.print(blank)
if n == 1 && result.List[0].Names == nil {
// single anonymous result; no ()'s
p.expr(result.List[0].Type)
return
}
p.parameters(result)
} else {
p.print("void ")
}
}
func (fs *FileSet) parseFieldList(fl *ast.FieldList) []gen.StructField {
if fl == nil || fl.NumFields() == 0 {
return nil
}
out := make([]gen.StructField, 0, fl.NumFields())
for i, field := range fl.List {
fds := fs.getField(field)
if len(fds) > 0 {
out = append(out, fds...)
} else {
warnf(" \u26a0 ignored struct field %d\n", i)
}
}
return out
}
// filterFieldList removes unexported fields (field names) from the field list
// in place and returns true if fields were removed. Anonymous fields are
// recorded with the parent type. filterType is called with the types of
// all remaining fields.
//
func (r *reader) filterFieldList(parent *namedType, fields *ast.FieldList) (removedFields bool) {
if fields == nil {
return
}
list := fields.List
j := 0
for _, field := range list {
keepField := false
if n := len(field.Names); n == 0 {
// anonymous field
name := r.recordAnonymousField(parent, field.Type)
if ast.IsExported(name) {
keepField = true
}
} else {
field.Names = filterIdentList(field.Names)
if len(field.Names) < n {
removedFields = true
}
if len(field.Names) > 0 {
keepField = true
}
}
if keepField {
r.filterType(nil, field.Type)
list[j] = field
j++
}
}
if j < len(list) {
removedFields = true
}
fields.List = list[0:j]
return
}
func (check *checker) collectMethods(list *ast.FieldList) (methods []*Method) {
if list == nil {
return
}
for _, f := range list.List {
typ := check.typ(f.Type, len(f.Names) > 0) // cycles are not ok for embedded interfaces
// the parser ensures that f.Tag is nil and we don't
// care if a constructed AST contains a non-nil tag
if len(f.Names) > 0 {
// methods (the parser ensures that there's only one
// and we don't care if a constructed AST has more)
sig, ok := typ.(*Signature)
if !ok {
check.invalidAST(f.Type.Pos(), "%s is not a method signature", typ)
continue
}
for _, name := range f.Names {
methods = append(methods, &Method{QualifiedName{check.pkg, name.Name}, sig})
}
} else {
// embedded interface
utyp := underlying(typ)
if ityp, ok := utyp.(*Interface); ok {
methods = append(methods, ityp.Methods...)
} else if utyp != Typ[Invalid] {
// if utyp is invalid, don't complain (the root cause was reported before)
check.errorf(f.Type.Pos(), "%s is not an interface type", typ)
}
}
}
// Check for double declarations.
// The parser inserts methods into an interface-local scope, so local
// double declarations are reported by the parser already. We need to
// check again for conflicts due to embedded interfaces. This will lead
// to a 2nd error message if the double declaration was reported before
// by the parser.
// TODO(gri) clean this up a bit
seen := make(map[string]bool)
for _, m := range methods {
if seen[m.Name] {
check.errorf(list.Pos(), "multiple methods named %s", m.Name)
return // keep multiple entries, lookup will only return the first entry
}
seen[m.Name] = true
}
return
}
func (fs *FileSet) parseFieldList(fl *ast.FieldList) []gen.StructField {
if fl == nil || fl.NumFields() == 0 {
return nil
}
out := make([]gen.StructField, 0, fl.NumFields())
for _, field := range fl.List {
pushstate(fieldName(field))
fds := fs.getField(field)
if len(fds) > 0 {
out = append(out, fds...)
} else {
warnln("ignored.")
}
popstate()
}
return out
}
func (p *parser) parseInterfaceType(n *parse.Node) ast.Expr {
keywordPos := token.Pos(n.Child(0).Pos())
n = n.Child(1)
specs := ast.FieldList{
Opening: token.Pos(n.Child(0).Pos()),
Closing: token.Pos(n.LastChild().Pos()),
}
if n.ChildCount() > 2 {
eachListItem(methodSpec, n.Child(1), func(item *parse.Node) {
specs.List = append(specs.List, p.parseMethodSpec(item))
})
}
return &ast.InterfaceType{
Interface: keywordPos,
Methods: &specs,
}
}
func (p *printer) signature(params, result *ast.FieldList) {
if params != nil {
p.parameters(params)
} else {
p.print(token.LPAREN, token.RPAREN)
}
n := result.NumFields()
if n > 0 {
// result != nil
p.print(blank)
if n == 1 && result.List[0].Names == nil {
// single anonymous result; no ()'s
p.expr(stripParensAlways(result.List[0].Type))
return
}
p.parameters(result)
}
}
func (check *checker) collectMethods(list *ast.FieldList) (methods ObjList) {
if list == nil {
return
}
for _, f := range list.List {
typ := check.typ(f.Type, len(f.Names) > 0) // cycles are not ok for embedded interfaces
// the parser ensures that f.Tag is nil and we don't
// care if a constructed AST contains a non-nil tag
if len(f.Names) > 0 {
// methods (the parser ensures that there's only one
// and we don't care if a constructed AST has more)
if _, ok := typ.(*Signature); !ok {
check.invalidAST(f.Type.Pos(), "%s is not a method signature", typ)
continue
}
for _, name := range f.Names {
obj := name.Obj
obj.Type = typ
methods = append(methods, obj)
}
} else {
// embedded interface
utyp := underlying(typ)
if ityp, ok := utyp.(*Interface); ok {
methods = append(methods, ityp.Methods...)
} else if utyp != Typ[Invalid] {
// if utyp is invalid, don't complain (the root cause was reported before)
check.errorf(f.Type.Pos(), "%s is not an interface type", typ)
}
}
}
// check for double declarations
methods.Sort()
prev := ""
for _, obj := range methods {
if obj.Name == prev {
check.errorf(list.Pos(), "multiple methods named %s", prev)
return // keep multiple entries, lookup will only return the first entry
}
}
return
}
func (check *checker) collectMethods(list *ast.FieldList) (methods ObjSet) {
if list == nil {
return
}
for _, f := range list.List {
typ := check.typ(f.Type, len(f.Names) > 0) // cycles are not ok for embedded interfaces
// the parser ensures that f.Tag is nil and we don't
// care if a constructed AST contains a non-nil tag
if len(f.Names) > 0 {
// methods (the parser ensures that there's only one
// and we don't care if a constructed AST has more)
sig, ok := typ.(*Signature)
if !ok {
check.invalidAST(f.Type.Pos(), "%s is not a method signature", typ)
continue
}
for _, name := range f.Names {
// TODO(gri) provide correct declaration info
obj := &Func{check.pkg, name.Name, sig, nil}
if alt := methods.Insert(obj); alt != nil {
check.errorf(list.Pos(), "multiple methods named %s", name.Name)
}
check.register(name, obj)
}
} else {
// embedded interface
utyp := typ.Underlying()
if ityp, ok := utyp.(*Interface); ok {
for _, obj := range ityp.methods.entries {
if alt := methods.Insert(obj); alt != nil {
check.errorf(list.Pos(), "multiple methods named %s", obj.Name())
}
}
} else if utyp != Typ[Invalid] {
// if utyp is invalid, don't complain (the root cause was reported before)
check.errorf(f.Type.Pos(), "%s is not an interface type", typ)
}
}
}
return
}
// Struct creates a struct{} expression. The arguments are a series
// of name/type/tag tuples. Name must be of type *ast.Ident, type
// must be of type ast.Expr, and tag must be of type *ast.BasicLit,
// The number of arguments must be a multiple of 3, or a run-time
// panic will occur.
func Struct(args ...ast.Expr) *ast.StructType {
fields := new(ast.FieldList)
if len(args)%3 != 0 {
panic("Number of args to FieldList must be a multiple of 3, got " + strconv.Itoa(len(args)))
}
for i := 0; i < len(args); i += 3 {
var field ast.Field
name, typ, tag := args[i], args[i+1], args[i+2]
if name != nil {
field.Names = []*ast.Ident{name.(*ast.Ident)}
}
if typ != nil {
field.Type = typ
}
if tag != nil {
field.Tag = tag.(*ast.BasicLit)
}
fields.List = append(fields.List, &field)
}
return &ast.StructType{Fields: fields}
}
func (f *File) validResults(results *ast.FieldList) *Error {
if results == nil || results.List == nil {
return nil
}
if results.NumFields() != 1 {
err := fmt.Sprint("ERROR: can only return at most one result, not:",
results.NumFields())
return &Error{errors.New(err), results.Pos()}
}
result := results.List[0]
if result == nil {
return nil
}
if result.Names != nil {
return &Error{errors.New(fmt.Sprint("ERROR: can only return nonnamed result, not:", result.Names)), result.Pos()}
}
typ := f.Info.TypeOf(result.Type)
if err := f.validResultType(typ); err != nil {
err.Pos = result.Pos()
if f.validVarDeclType(typ) == nil {
err.Err = errors.New(fmt.Sprint(err.Err) + ", type only valid as a var decl, or param")
} else if f.validParamType(typ) == nil {
err.Err = errors.New(fmt.Sprint(err.Err) + ", type only valid as func param type")
}
return err
}
return nil
}
// belongsToReceiver checks if a function with these return types belongs to
// a receiver. If it belongs to a receiver, the name of that receiver will be
// returned with ok set to true. Otherwise ok will be false.
// Behavior should be similar to how go doc decides when a function belongs to
// a receiver (gosrc/pkg/go/doc/reader.go).
func (p *tagParser) belongsToReceiver(types *ast.FieldList) (name string, ok bool) {
if types == nil || types.NumFields() == 0 {
return "", false
}
// If the first return type has more than 1 result associated with
// it, it should not belong to that receiver.
// Similar behavior as go doc (go source/.
if len(types.List[0].Names) > 1 {
return "", false
}
// get name of the first return type
t := getType(types.List[0].Type, false)
// check if it exists in the current list of known types
for _, knownType := range p.types {
if t == knownType {
return knownType, true
}
}
return "", false
}
// removeFieldNames removes names from the FieldList in place.
// This is used to remove names from return values
func removeFieldNames(fl *ast.FieldList) {
l := []*ast.Field{}
for _, f := range fl.List {
if f.Names == nil {
l = append(l, f)
} else {
for range f.Names {
nf := *f
nf.Names = nil
l = append(l, &nf)
}
}
}
fl.List = l
}
// filterFieldList removes unexported fields (field names) from the field list
// in place and returns true if fields were removed. Removed fields that are
// anonymous (embedded) fields are added as embedded types to base. filterType
// is called with the types of all remaining fields.
//
func (r *reader) filterFieldList(base *baseType, fields *ast.FieldList) (removedFields bool) {
if fields == nil {
return
}
list := fields.List
j := 0
for _, field := range list {
keepField := false
if n := len(field.Names); n == 0 {
// anonymous field
name, imp := baseTypeName(field.Type)
if ast.IsExported(name) {
// we keep the field - in this case r.readDecl
// will take care of adding the embedded type
keepField = true
} else if base != nil && !imp {
// we don't keep the field - add it as an embedded
// type so we won't loose its methods, if any
if embedded := r.lookupType(name); embedded != nil {
_, ptr := field.Type.(*ast.StarExpr)
base.addEmbeddedType(embedded, ptr)
}
}
} else {
field.Names = filterIdentList(field.Names)
if len(field.Names) < n {
removedFields = true
}
if len(field.Names) > 0 {
keepField = true
}
}
if keepField {
r.filterType(nil, field.Type)
list[j] = field
j++
}
}
if j < len(list) {
removedFields = true
}
fields.List = list[0:j]
return
}
// filterFieldList removes unexported fields (field names) from the field list
// in place and returns true if fields were removed. Anonymous fields are
// recorded with the parent type. filterType is called with the types of
// all remaining fields.
//
func (r *reader) filterFieldList(parent *namedType, fields *ast.FieldList, ityp *ast.InterfaceType) (removedFields bool) {
if fields == nil {
return
}
list := fields.List
j := 0
for _, field := range list {
keepField := false
if n := len(field.Names); n == 0 {
// anonymous field
fname := r.recordAnonymousField(parent, field.Type)
if ast.IsExported(fname) {
keepField = true
} else if ityp != nil && fname == "error" {
// possibly the predeclared error interface; keep
// it for now but remember this interface so that
// it can be fixed if error is also defined locally
keepField = true
r.remember(ityp)
}
} else {
field.Names = filterIdentList(field.Names, false)
if len(field.Names) < n {
removedFields = true
}
if len(field.Names) > 0 {
keepField = true
}
}
if keepField {
r.filterType(nil, field.Type)
list[j] = field
j++
}
}
if j < len(list) {
removedFields = true
}
fields.List = list[0:j]
return
}
// funcType type-checks a function or method type.
func (check *Checker) funcType(sig *Signature, recvPar *ast.FieldList, ftyp *ast.FuncType) {
scope := NewScope(check.scope, token.NoPos, token.NoPos, "function")
check.recordScope(ftyp, scope)
recvList, _ := check.collectParams(scope, recvPar, false)
params, variadic := check.collectParams(scope, ftyp.Params, true)
results, _ := check.collectParams(scope, ftyp.Results, false)
if recvPar != nil {
// recv parameter list present (may be empty)
// spec: "The receiver is specified via an extra parameter section preceding the
// method name. That parameter section must declare a single parameter, the receiver."
var recv *Var
switch len(recvList) {
case 0:
check.error(recvPar.Pos(), "method is missing receiver")
recv = NewParam(0, nil, "", Typ[Invalid]) // ignore recv below
default:
// more than one receiver
check.error(recvList[len(recvList)-1].Pos(), "method must have exactly one receiver")
fallthrough // continue with first receiver
case 1:
recv = recvList[0]
}
// spec: "The receiver type must be of the form T or *T where T is a type name."
// (ignore invalid types - error was reported before)
if t, _ := deref(recv.typ); t != Typ[Invalid] {
var err string
if T, _ := t.(*Named); T != nil {
// spec: "The type denoted by T is called the receiver base type; it must not
// be a pointer or interface type and it must be declared in the same package
// as the method."
if T.obj.pkg != check.pkg {
err = "type not defined in this package"
} else {
// TODO(gri) This is not correct if the underlying type is unknown yet.
switch u := T.underlying.(type) {
case *Basic:
// unsafe.Pointer is treated like a regular pointer
if u.kind == UnsafePointer {
err = "unsafe.Pointer"
}
case *Pointer, *Interface:
err = "pointer or interface type"
}
}
} else {
err = "basic or unnamed type"
}
if err != "" {
check.errorf(recv.pos, "invalid receiver %s (%s)", recv.typ, err)
// ok to continue
}
}
sig.recv = recv
}
sig.scope = scope
sig.params = NewTuple(params...)
sig.results = NewTuple(results...)
sig.variadic = variadic
}
// declReturnValues builds the return part of the call
//
func declReturnValues(results *ast.FieldList) ([]ast.Stmt, error) {
if results.NumFields() == 0 {
return nil, nil
}
stmts := []ast.Stmt{}
for i, f := range results.List {
// var r_X type
stmts = append(stmts, &ast.DeclStmt{
Decl: &ast.GenDecl{
Tok: token.VAR,
Specs: []ast.Spec{
&ast.ValueSpec{
Names: []*ast.Ident{
ast.NewIdent(fmt.Sprintf("r_%d", i)),
},
Type: f.Type,
},
},
},
})
// if r[X] != nil {
// r_X = r[X].(type)
// }
stmts = append(stmts, &ast.IfStmt{
Cond: &ast.BinaryExpr{
X: &ast.IndexExpr{
X: ast.NewIdent("r"),
Index: &ast.BasicLit{
Kind: token.INT,
Value: fmt.Sprintf("%d", i),
},
},
Op: token.NEQ,
Y: ast.NewIdent("nil"),
},
Body: &ast.BlockStmt{
List: []ast.Stmt{
&ast.AssignStmt{
Lhs: []ast.Expr{
ast.NewIdent(fmt.Sprintf("r_%d", i)),
},
Tok: token.ASSIGN,
Rhs: []ast.Expr{
&ast.TypeAssertExpr{
X: &ast.IndexExpr{
X: ast.NewIdent("r"),
Index: &ast.BasicLit{
Kind: token.INT,
Value: fmt.Sprintf("%d", i),
},
},
Type: f.Type,
},
},
},
},
},
})
}
return stmts, nil
}
