[dev.typeparams] cmd/compile/internal/types2: move struct checking into separate file

This only moves functionality from one file into another.
Except for import adjustments there are no changes to the
code.

Change-Id: I8dff41fe82693c96b09a152975c3fd1e3b439e8d
Reviewed-on: https://go-review.googlesource.com/c/go/+/321589
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
This commit is contained in:
Robert Griesemer 2021-05-20 14:47:40 -07:00
parent 211244e172
commit cfe0250497
2 changed files with 165 additions and 156 deletions

View file

@ -0,0 +1,165 @@
// Copyright 2021 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package types2
import (
"cmd/compile/internal/syntax"
"strconv"
)
func (check *Checker) structType(styp *Struct, e *syntax.StructType) {
if e.FieldList == nil {
return
}
// struct fields and tags
var fields []*Var
var tags []string
// for double-declaration checks
var fset objset
// current field typ and tag
var typ Type
var tag string
add := func(ident *syntax.Name, embedded bool, pos syntax.Pos) {
if tag != "" && tags == nil {
tags = make([]string, len(fields))
}
if tags != nil {
tags = append(tags, tag)
}
name := ident.Value
fld := NewField(pos, check.pkg, name, typ, embedded)
// spec: "Within a struct, non-blank field names must be unique."
if name == "_" || check.declareInSet(&fset, pos, fld) {
fields = append(fields, fld)
check.recordDef(ident, fld)
}
}
// addInvalid adds an embedded field of invalid type to the struct for
// fields with errors; this keeps the number of struct fields in sync
// with the source as long as the fields are _ or have different names
// (issue #25627).
addInvalid := func(ident *syntax.Name, pos syntax.Pos) {
typ = Typ[Invalid]
tag = ""
add(ident, true, pos)
}
var prev syntax.Expr
for i, f := range e.FieldList {
// Fields declared syntactically with the same type (e.g.: a, b, c T)
// share the same type expression. Only check type if it's a new type.
if i == 0 || f.Type != prev {
typ = check.varType(f.Type)
prev = f.Type
}
tag = ""
if i < len(e.TagList) {
tag = check.tag(e.TagList[i])
}
if f.Name != nil {
// named field
add(f.Name, false, f.Name.Pos())
} else {
// embedded field
// spec: "An embedded type must be specified as a type name T or as a
// pointer to a non-interface type name *T, and T itself may not be a
// pointer type."
pos := syntax.StartPos(f.Type)
name := embeddedFieldIdent(f.Type)
if name == nil {
check.errorf(pos, "invalid embedded field type %s", f.Type)
name = &syntax.Name{Value: "_"} // TODO(gri) need to set position to pos
addInvalid(name, pos)
continue
}
add(name, true, pos)
// Because we have a name, typ must be of the form T or *T, where T is the name
// of a (named or alias) type, and t (= deref(typ)) must be the type of T.
// We must delay this check to the end because we don't want to instantiate
// (via under(t)) a possibly incomplete type.
embeddedTyp := typ // for closure below
embeddedPos := pos
check.later(func() {
t, isPtr := deref(embeddedTyp)
switch t := optype(t).(type) {
case *Basic:
if t == Typ[Invalid] {
// error was reported before
return
}
// unsafe.Pointer is treated like a regular pointer
if t.kind == UnsafePointer {
check.error(embeddedPos, "embedded field type cannot be unsafe.Pointer")
}
case *Pointer:
check.error(embeddedPos, "embedded field type cannot be a pointer")
case *Interface:
if isPtr {
check.error(embeddedPos, "embedded field type cannot be a pointer to an interface")
}
}
})
}
}
styp.fields = fields
styp.tags = tags
}
func embeddedFieldIdent(e syntax.Expr) *syntax.Name {
switch e := e.(type) {
case *syntax.Name:
return e
case *syntax.Operation:
if base := ptrBase(e); base != nil {
// *T is valid, but **T is not
if op, _ := base.(*syntax.Operation); op == nil || ptrBase(op) == nil {
return embeddedFieldIdent(e.X)
}
}
case *syntax.SelectorExpr:
return e.Sel
case *syntax.IndexExpr:
return embeddedFieldIdent(e.X)
}
return nil // invalid embedded field
}
func (check *Checker) declareInSet(oset *objset, pos syntax.Pos, obj Object) bool {
if alt := oset.insert(obj); alt != nil {
var err error_
err.errorf(pos, "%s redeclared", obj.Name())
err.recordAltDecl(alt)
check.report(&err)
return false
}
return true
}
func (check *Checker) tag(t *syntax.BasicLit) string {
// If t.Bad, an error was reported during parsing.
if t != nil && !t.Bad {
if t.Kind == syntax.StringLit {
if val, err := strconv.Unquote(t.Value); err == nil {
return val
}
}
check.errorf(t, invalidAST+"incorrect tag syntax: %q", t.Value)
}
return ""
}
func ptrBase(x *syntax.Operation) syntax.Expr {
if x.Op == syntax.Mul && x.Y == nil {
return x.X
}
return nil
}

View file

@ -10,7 +10,6 @@ import (
"cmd/compile/internal/syntax"
"fmt"
"go/constant"
"strconv"
"strings"
)
@ -800,158 +799,3 @@ func (check *Checker) collectParams(scope *Scope, list []*syntax.Field, type0 sy
return
}
func (check *Checker) declareInSet(oset *objset, pos syntax.Pos, obj Object) bool {
if alt := oset.insert(obj); alt != nil {
var err error_
err.errorf(pos, "%s redeclared", obj.Name())
err.recordAltDecl(alt)
check.report(&err)
return false
}
return true
}
func (check *Checker) tag(t *syntax.BasicLit) string {
// If t.Bad, an error was reported during parsing.
if t != nil && !t.Bad {
if t.Kind == syntax.StringLit {
if val, err := strconv.Unquote(t.Value); err == nil {
return val
}
}
check.errorf(t, invalidAST+"incorrect tag syntax: %q", t.Value)
}
return ""
}
func (check *Checker) structType(styp *Struct, e *syntax.StructType) {
if e.FieldList == nil {
return
}
// struct fields and tags
var fields []*Var
var tags []string
// for double-declaration checks
var fset objset
// current field typ and tag
var typ Type
var tag string
add := func(ident *syntax.Name, embedded bool, pos syntax.Pos) {
if tag != "" && tags == nil {
tags = make([]string, len(fields))
}
if tags != nil {
tags = append(tags, tag)
}
name := ident.Value
fld := NewField(pos, check.pkg, name, typ, embedded)
// spec: "Within a struct, non-blank field names must be unique."
if name == "_" || check.declareInSet(&fset, pos, fld) {
fields = append(fields, fld)
check.recordDef(ident, fld)
}
}
// addInvalid adds an embedded field of invalid type to the struct for
// fields with errors; this keeps the number of struct fields in sync
// with the source as long as the fields are _ or have different names
// (issue #25627).
addInvalid := func(ident *syntax.Name, pos syntax.Pos) {
typ = Typ[Invalid]
tag = ""
add(ident, true, pos)
}
var prev syntax.Expr
for i, f := range e.FieldList {
// Fields declared syntactically with the same type (e.g.: a, b, c T)
// share the same type expression. Only check type if it's a new type.
if i == 0 || f.Type != prev {
typ = check.varType(f.Type)
prev = f.Type
}
tag = ""
if i < len(e.TagList) {
tag = check.tag(e.TagList[i])
}
if f.Name != nil {
// named field
add(f.Name, false, f.Name.Pos())
} else {
// embedded field
// spec: "An embedded type must be specified as a type name T or as a
// pointer to a non-interface type name *T, and T itself may not be a
// pointer type."
pos := syntax.StartPos(f.Type)
name := embeddedFieldIdent(f.Type)
if name == nil {
check.errorf(pos, "invalid embedded field type %s", f.Type)
name = &syntax.Name{Value: "_"} // TODO(gri) need to set position to pos
addInvalid(name, pos)
continue
}
add(name, true, pos)
// Because we have a name, typ must be of the form T or *T, where T is the name
// of a (named or alias) type, and t (= deref(typ)) must be the type of T.
// We must delay this check to the end because we don't want to instantiate
// (via under(t)) a possibly incomplete type.
embeddedTyp := typ // for closure below
embeddedPos := pos
check.later(func() {
t, isPtr := deref(embeddedTyp)
switch t := optype(t).(type) {
case *Basic:
if t == Typ[Invalid] {
// error was reported before
return
}
// unsafe.Pointer is treated like a regular pointer
if t.kind == UnsafePointer {
check.error(embeddedPos, "embedded field type cannot be unsafe.Pointer")
}
case *Pointer:
check.error(embeddedPos, "embedded field type cannot be a pointer")
case *Interface:
if isPtr {
check.error(embeddedPos, "embedded field type cannot be a pointer to an interface")
}
}
})
}
}
styp.fields = fields
styp.tags = tags
}
func embeddedFieldIdent(e syntax.Expr) *syntax.Name {
switch e := e.(type) {
case *syntax.Name:
return e
case *syntax.Operation:
if base := ptrBase(e); base != nil {
// *T is valid, but **T is not
if op, _ := base.(*syntax.Operation); op == nil || ptrBase(op) == nil {
return embeddedFieldIdent(e.X)
}
}
case *syntax.SelectorExpr:
return e.Sel
case *syntax.IndexExpr:
return embeddedFieldIdent(e.X)
}
return nil // invalid embedded field
}
func ptrBase(x *syntax.Operation) syntax.Expr {
if x.Op == syntax.Mul && x.Y == nil {
return x.X
}
return nil
}