mirror of
https://github.com/golang/go
synced 2024-11-18 15:24:41 -07:00
85ad76014a
Broken by CLs 10994 and 10800. Fixes golang/go#11194. Change-Id: Ic071fae6bf7e8ac9518d84c74c98d1d7233c2025 Reviewed-on: https://go-review.googlesource.com/11004 Reviewed-by: Robert Griesemer <gri@golang.org>
95 lines
2.4 KiB
Go
95 lines
2.4 KiB
Go
// Copyright 2015 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.
|
|
|
|
// This file defines the check for unused results of calls to certain
|
|
// pure functions.
|
|
|
|
package main
|
|
|
|
import (
|
|
"flag"
|
|
"go/ast"
|
|
"go/token"
|
|
"strings"
|
|
|
|
"golang.org/x/tools/go/types"
|
|
)
|
|
|
|
var unusedFuncsFlag = flag.String("unusedfuncs",
|
|
"errors.New,fmt.Errorf,fmt.Sprintf,fmt.Sprint,sort.Reverse",
|
|
"comma-separated list of functions whose results must be used")
|
|
|
|
var unusedStringMethodsFlag = flag.String("unusedstringmethods",
|
|
"Error,String",
|
|
"comma-separated list of names of methods of type func() string whose results must be used")
|
|
|
|
func init() {
|
|
register("unusedresult",
|
|
"check for unused result of calls to functions in -unusedfuncs list and methods in -unusedstringmethods list",
|
|
checkUnusedResult,
|
|
exprStmt)
|
|
}
|
|
|
|
// func() string
|
|
var sigNoArgsStringResult = types.NewSignature(nil, nil,
|
|
types.NewTuple(types.NewVar(token.NoPos, nil, "", types.Typ[types.String])),
|
|
false)
|
|
|
|
var unusedFuncs = make(map[string]bool)
|
|
var unusedStringMethods = make(map[string]bool)
|
|
|
|
func initUnusedFlags() {
|
|
commaSplit := func(s string, m map[string]bool) {
|
|
if s != "" {
|
|
for _, name := range strings.Split(s, ",") {
|
|
if len(name) == 0 {
|
|
flag.Usage()
|
|
}
|
|
m[name] = true
|
|
}
|
|
}
|
|
}
|
|
commaSplit(*unusedFuncsFlag, unusedFuncs)
|
|
commaSplit(*unusedStringMethodsFlag, unusedStringMethods)
|
|
}
|
|
|
|
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)
|
|
}
|
|
}
|
|
}
|
|
}
|