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-rw-r--r--src/cmd/gofix/fix.go422
1 files changed, 422 insertions, 0 deletions
diff --git a/src/cmd/gofix/fix.go b/src/cmd/gofix/fix.go
new file mode 100644
index 000000000..0852ce21e
--- /dev/null
+++ b/src/cmd/gofix/fix.go
@@ -0,0 +1,422 @@
+// Copyright 2011 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 main
+
+import (
+ "fmt"
+ "go/ast"
+ "go/token"
+ "os"
+ "strconv"
+)
+
+type fix struct {
+ name string
+ f func(*ast.File) bool
+ desc string
+}
+
+// main runs sort.Sort(fixes) after init process is done.
+type fixlist []fix
+
+func (f fixlist) Len() int { return len(f) }
+func (f fixlist) Swap(i, j int) { f[i], f[j] = f[j], f[i] }
+func (f fixlist) Less(i, j int) bool { return f[i].name < f[j].name }
+
+var fixes fixlist
+
+func register(f fix) {
+ fixes = append(fixes, f)
+}
+
+// walk traverses the AST x, calling visit(y) for each node y in the tree but
+// also with a pointer to each ast.Expr, ast.Stmt, and *ast.BlockStmt,
+// in a bottom-up traversal.
+func walk(x interface{}, visit func(interface{})) {
+ walkBeforeAfter(x, nop, visit)
+}
+
+func nop(interface{}) {}
+
+// walkBeforeAfter is like walk but calls before(x) before traversing
+// x's children and after(x) afterward.
+func walkBeforeAfter(x interface{}, before, after func(interface{})) {
+ before(x)
+
+ switch n := x.(type) {
+ default:
+ panic(fmt.Errorf("unexpected type %T in walkBeforeAfter", x))
+
+ case nil:
+
+ // pointers to interfaces
+ case *ast.Decl:
+ walkBeforeAfter(*n, before, after)
+ case *ast.Expr:
+ walkBeforeAfter(*n, before, after)
+ case *ast.Spec:
+ walkBeforeAfter(*n, before, after)
+ case *ast.Stmt:
+ walkBeforeAfter(*n, before, after)
+
+ // pointers to struct pointers
+ case **ast.BlockStmt:
+ walkBeforeAfter(*n, before, after)
+ case **ast.CallExpr:
+ walkBeforeAfter(*n, before, after)
+ case **ast.FieldList:
+ walkBeforeAfter(*n, before, after)
+ case **ast.FuncType:
+ walkBeforeAfter(*n, before, after)
+
+ // pointers to slices
+ case *[]ast.Stmt:
+ walkBeforeAfter(*n, before, after)
+ case *[]ast.Expr:
+ walkBeforeAfter(*n, before, after)
+ case *[]ast.Decl:
+ walkBeforeAfter(*n, before, after)
+ case *[]ast.Spec:
+ walkBeforeAfter(*n, before, after)
+ case *[]*ast.File:
+ walkBeforeAfter(*n, before, after)
+
+ // These are ordered and grouped to match ../../pkg/go/ast/ast.go
+ case *ast.Field:
+ walkBeforeAfter(&n.Type, before, after)
+ case *ast.FieldList:
+ for _, field := range n.List {
+ walkBeforeAfter(field, before, after)
+ }
+ case *ast.BadExpr:
+ case *ast.Ident:
+ case *ast.Ellipsis:
+ case *ast.BasicLit:
+ case *ast.FuncLit:
+ walkBeforeAfter(&n.Type, before, after)
+ walkBeforeAfter(&n.Body, before, after)
+ case *ast.CompositeLit:
+ walkBeforeAfter(&n.Type, before, after)
+ walkBeforeAfter(&n.Elts, before, after)
+ case *ast.ParenExpr:
+ walkBeforeAfter(&n.X, before, after)
+ case *ast.SelectorExpr:
+ walkBeforeAfter(&n.X, before, after)
+ case *ast.IndexExpr:
+ walkBeforeAfter(&n.X, before, after)
+ walkBeforeAfter(&n.Index, before, after)
+ case *ast.SliceExpr:
+ walkBeforeAfter(&n.X, before, after)
+ if n.Low != nil {
+ walkBeforeAfter(&n.Low, before, after)
+ }
+ if n.High != nil {
+ walkBeforeAfter(&n.High, before, after)
+ }
+ case *ast.TypeAssertExpr:
+ walkBeforeAfter(&n.X, before, after)
+ walkBeforeAfter(&n.Type, before, after)
+ case *ast.CallExpr:
+ walkBeforeAfter(&n.Fun, before, after)
+ walkBeforeAfter(&n.Args, before, after)
+ case *ast.StarExpr:
+ walkBeforeAfter(&n.X, before, after)
+ case *ast.UnaryExpr:
+ walkBeforeAfter(&n.X, before, after)
+ case *ast.BinaryExpr:
+ walkBeforeAfter(&n.X, before, after)
+ walkBeforeAfter(&n.Y, before, after)
+ case *ast.KeyValueExpr:
+ walkBeforeAfter(&n.Key, before, after)
+ walkBeforeAfter(&n.Value, before, after)
+
+ case *ast.ArrayType:
+ walkBeforeAfter(&n.Len, before, after)
+ walkBeforeAfter(&n.Elt, before, after)
+ case *ast.StructType:
+ walkBeforeAfter(&n.Fields, before, after)
+ case *ast.FuncType:
+ walkBeforeAfter(&n.Params, before, after)
+ if n.Results != nil {
+ walkBeforeAfter(&n.Results, before, after)
+ }
+ case *ast.InterfaceType:
+ walkBeforeAfter(&n.Methods, before, after)
+ case *ast.MapType:
+ walkBeforeAfter(&n.Key, before, after)
+ walkBeforeAfter(&n.Value, before, after)
+ case *ast.ChanType:
+ walkBeforeAfter(&n.Value, before, after)
+
+ case *ast.BadStmt:
+ case *ast.DeclStmt:
+ walkBeforeAfter(&n.Decl, before, after)
+ case *ast.EmptyStmt:
+ case *ast.LabeledStmt:
+ walkBeforeAfter(&n.Stmt, before, after)
+ case *ast.ExprStmt:
+ walkBeforeAfter(&n.X, before, after)
+ case *ast.SendStmt:
+ walkBeforeAfter(&n.Chan, before, after)
+ walkBeforeAfter(&n.Value, before, after)
+ case *ast.IncDecStmt:
+ walkBeforeAfter(&n.X, before, after)
+ case *ast.AssignStmt:
+ walkBeforeAfter(&n.Lhs, before, after)
+ walkBeforeAfter(&n.Rhs, before, after)
+ case *ast.GoStmt:
+ walkBeforeAfter(&n.Call, before, after)
+ case *ast.DeferStmt:
+ walkBeforeAfter(&n.Call, before, after)
+ case *ast.ReturnStmt:
+ walkBeforeAfter(&n.Results, before, after)
+ case *ast.BranchStmt:
+ case *ast.BlockStmt:
+ walkBeforeAfter(&n.List, before, after)
+ case *ast.IfStmt:
+ walkBeforeAfter(&n.Init, before, after)
+ walkBeforeAfter(&n.Cond, before, after)
+ walkBeforeAfter(&n.Body, before, after)
+ walkBeforeAfter(&n.Else, before, after)
+ case *ast.CaseClause:
+ walkBeforeAfter(&n.List, before, after)
+ walkBeforeAfter(&n.Body, before, after)
+ case *ast.SwitchStmt:
+ walkBeforeAfter(&n.Init, before, after)
+ walkBeforeAfter(&n.Tag, before, after)
+ walkBeforeAfter(&n.Body, before, after)
+ case *ast.TypeSwitchStmt:
+ walkBeforeAfter(&n.Init, before, after)
+ walkBeforeAfter(&n.Assign, before, after)
+ walkBeforeAfter(&n.Body, before, after)
+ case *ast.CommClause:
+ walkBeforeAfter(&n.Comm, before, after)
+ walkBeforeAfter(&n.Body, before, after)
+ case *ast.SelectStmt:
+ walkBeforeAfter(&n.Body, before, after)
+ case *ast.ForStmt:
+ walkBeforeAfter(&n.Init, before, after)
+ walkBeforeAfter(&n.Cond, before, after)
+ walkBeforeAfter(&n.Post, before, after)
+ walkBeforeAfter(&n.Body, before, after)
+ case *ast.RangeStmt:
+ walkBeforeAfter(&n.Key, before, after)
+ walkBeforeAfter(&n.Value, before, after)
+ walkBeforeAfter(&n.X, before, after)
+ walkBeforeAfter(&n.Body, before, after)
+
+ case *ast.ImportSpec:
+ case *ast.ValueSpec:
+ walkBeforeAfter(&n.Type, before, after)
+ walkBeforeAfter(&n.Values, before, after)
+ case *ast.TypeSpec:
+ walkBeforeAfter(&n.Type, before, after)
+
+ case *ast.BadDecl:
+ case *ast.GenDecl:
+ walkBeforeAfter(&n.Specs, before, after)
+ case *ast.FuncDecl:
+ if n.Recv != nil {
+ walkBeforeAfter(&n.Recv, before, after)
+ }
+ walkBeforeAfter(&n.Type, before, after)
+ if n.Body != nil {
+ walkBeforeAfter(&n.Body, before, after)
+ }
+
+ case *ast.File:
+ walkBeforeAfter(&n.Decls, before, after)
+
+ case *ast.Package:
+ walkBeforeAfter(&n.Files, before, after)
+
+ case []*ast.File:
+ for i := range n {
+ walkBeforeAfter(&n[i], before, after)
+ }
+ case []ast.Decl:
+ for i := range n {
+ walkBeforeAfter(&n[i], before, after)
+ }
+ case []ast.Expr:
+ for i := range n {
+ walkBeforeAfter(&n[i], before, after)
+ }
+ case []ast.Stmt:
+ for i := range n {
+ walkBeforeAfter(&n[i], before, after)
+ }
+ case []ast.Spec:
+ for i := range n {
+ walkBeforeAfter(&n[i], before, after)
+ }
+ }
+ after(x)
+}
+
+// imports returns true if f imports path.
+func imports(f *ast.File, path string) bool {
+ for _, s := range f.Imports {
+ t, err := strconv.Unquote(s.Path.Value)
+ if err == nil && t == path {
+ return true
+ }
+ }
+ return false
+}
+
+// isPkgDot returns true if t is the expression "pkg.name"
+// where pkg is an imported identifier.
+func isPkgDot(t ast.Expr, pkg, name string) bool {
+ sel, ok := t.(*ast.SelectorExpr)
+ return ok && isTopName(sel.X, pkg) && sel.Sel.String() == name
+}
+
+// isPtrPkgDot returns true if f is the expression "*pkg.name"
+// where pkg is an imported identifier.
+func isPtrPkgDot(t ast.Expr, pkg, name string) bool {
+ ptr, ok := t.(*ast.StarExpr)
+ return ok && isPkgDot(ptr.X, pkg, name)
+}
+
+// isTopName returns true if n is a top-level unresolved identifier with the given name.
+func isTopName(n ast.Expr, name string) bool {
+ id, ok := n.(*ast.Ident)
+ return ok && id.Name == name && id.Obj == nil
+}
+
+// isName returns true if n is an identifier with the given name.
+func isName(n ast.Expr, name string) bool {
+ id, ok := n.(*ast.Ident)
+ return ok && id.String() == name
+}
+
+// isCall returns true if t is a call to pkg.name.
+func isCall(t ast.Expr, pkg, name string) bool {
+ call, ok := t.(*ast.CallExpr)
+ return ok && isPkgDot(call.Fun, pkg, name)
+}
+
+// If n is an *ast.Ident, isIdent returns it; otherwise isIdent returns nil.
+func isIdent(n interface{}) *ast.Ident {
+ id, _ := n.(*ast.Ident)
+ return id
+}
+
+// refersTo returns true if n is a reference to the same object as x.
+func refersTo(n ast.Node, x *ast.Ident) bool {
+ id, ok := n.(*ast.Ident)
+ // The test of id.Name == x.Name handles top-level unresolved
+ // identifiers, which all have Obj == nil.
+ return ok && id.Obj == x.Obj && id.Name == x.Name
+}
+
+// isBlank returns true if n is the blank identifier.
+func isBlank(n ast.Expr) bool {
+ return isName(n, "_")
+}
+
+// isEmptyString returns true if n is an empty string literal.
+func isEmptyString(n ast.Expr) bool {
+ lit, ok := n.(*ast.BasicLit)
+ return ok && lit.Kind == token.STRING && len(lit.Value) == 2
+}
+
+func warn(pos token.Pos, msg string, args ...interface{}) {
+ if pos.IsValid() {
+ msg = "%s: " + msg
+ arg1 := []interface{}{fset.Position(pos).String()}
+ args = append(arg1, args...)
+ }
+ fmt.Fprintf(os.Stderr, msg+"\n", args...)
+}
+
+// countUses returns the number of uses of the identifier x in scope.
+func countUses(x *ast.Ident, scope []ast.Stmt) int {
+ count := 0
+ ff := func(n interface{}) {
+ if n, ok := n.(ast.Node); ok && refersTo(n, x) {
+ count++
+ }
+ }
+ for _, n := range scope {
+ walk(n, ff)
+ }
+ return count
+}
+
+// rewriteUses replaces all uses of the identifier x and !x in scope
+// with f(x.Pos()) and fnot(x.Pos()).
+func rewriteUses(x *ast.Ident, f, fnot func(token.Pos) ast.Expr, scope []ast.Stmt) {
+ var lastF ast.Expr
+ ff := func(n interface{}) {
+ ptr, ok := n.(*ast.Expr)
+ if !ok {
+ return
+ }
+ nn := *ptr
+
+ // The child node was just walked and possibly replaced.
+ // If it was replaced and this is a negation, replace with fnot(p).
+ not, ok := nn.(*ast.UnaryExpr)
+ if ok && not.Op == token.NOT && not.X == lastF {
+ *ptr = fnot(nn.Pos())
+ return
+ }
+ if refersTo(nn, x) {
+ lastF = f(nn.Pos())
+ *ptr = lastF
+ }
+ }
+ for _, n := range scope {
+ walk(n, ff)
+ }
+}
+
+// assignsTo returns true if any of the code in scope assigns to or takes the address of x.
+func assignsTo(x *ast.Ident, scope []ast.Stmt) bool {
+ assigned := false
+ ff := func(n interface{}) {
+ if assigned {
+ return
+ }
+ switch n := n.(type) {
+ case *ast.UnaryExpr:
+ // use of &x
+ if n.Op == token.AND && refersTo(n.X, x) {
+ assigned = true
+ return
+ }
+ case *ast.AssignStmt:
+ for _, l := range n.Lhs {
+ if refersTo(l, x) {
+ assigned = true
+ return
+ }
+ }
+ }
+ }
+ for _, n := range scope {
+ if assigned {
+ break
+ }
+ walk(n, ff)
+ }
+ return assigned
+}
+
+// newPkgDot returns an ast.Expr referring to "pkg.name" at position pos.
+func newPkgDot(pos token.Pos, pkg, name string) ast.Expr {
+ return &ast.SelectorExpr{
+ X: &ast.Ident{
+ NamePos: pos,
+ Name: pkg,
+ },
+ Sel: &ast.Ident{
+ NamePos: pos,
+ Name: name,
+ },
+ }
+}
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-15 04:36:16 +0000