src

Go monorepo.
git clone git://code.dwrz.net/src
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s1004.go (2217B)

      1 package s1004
      2 
      3 import (
      4 	"fmt"
      5 	"go/ast"
      6 	"go/token"
      7 
      8 	"honnef.co/go/tools/analysis/code"
      9 	"honnef.co/go/tools/analysis/edit"
     10 	"honnef.co/go/tools/analysis/facts/generated"
     11 	"honnef.co/go/tools/analysis/lint"
     12 	"honnef.co/go/tools/analysis/report"
     13 	"honnef.co/go/tools/pattern"
     14 
     15 	"golang.org/x/tools/go/analysis"
     16 )
     17 
     18 var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
     19 	Analyzer: &analysis.Analyzer{
     20 		Name:     "S1004",
     21 		Run:      CheckBytesCompare,
     22 		Requires: append([]*analysis.Analyzer{generated.Analyzer}, code.RequiredAnalyzers...),
     23 	},
     24 	Doc: &lint.RawDocumentation{
     25 		Title:   `Replace call to \'bytes.Compare\' with \'bytes.Equal\'`,
     26 		Before:  `if bytes.Compare(x, y) == 0 {}`,
     27 		After:   `if bytes.Equal(x, y) {}`,
     28 		Since:   "2017.1",
     29 		MergeIf: lint.MergeIfAny,
     30 	},
     31 })
     32 
     33 var Analyzer = SCAnalyzer.Analyzer
     34 
     35 var (
     36 	checkBytesCompareQ  = pattern.MustParse(`(BinaryExpr (CallExpr (Symbol "bytes.Compare") args) op@(Or "==" "!=") (IntegerLiteral "0"))`)
     37 	checkBytesCompareRe = pattern.MustParse(`(CallExpr (SelectorExpr (Ident "bytes") (Ident "Equal")) args)`)
     38 	checkBytesCompareRn = pattern.MustParse(`(UnaryExpr "!" (CallExpr (SelectorExpr (Ident "bytes") (Ident "Equal")) args))`)
     39 )
     40 
     41 func CheckBytesCompare(pass *analysis.Pass) (any, error) {
     42 	if pass.Pkg.Path() == "bytes" || pass.Pkg.Path() == "bytes_test" {
     43 		// the bytes package is free to use bytes.Compare as it sees fit
     44 		return nil, nil
     45 	}
     46 	for node, m := range code.Matches(pass, checkBytesCompareQ) {
     47 		args := report.RenderArgs(pass, m.State["args"].([]ast.Expr))
     48 		prefix := ""
     49 		if m.State["op"].(token.Token) == token.NEQ {
     50 			prefix = "!"
     51 		}
     52 
     53 		var fix analysis.SuggestedFix
     54 		switch tok := m.State["op"].(token.Token); tok {
     55 		case token.EQL:
     56 			fix = edit.Fix("Simplify use of bytes.Compare", edit.ReplaceWithPattern(pass.Fset, node, checkBytesCompareRe, m.State))
     57 		case token.NEQ:
     58 			fix = edit.Fix("Simplify use of bytes.Compare", edit.ReplaceWithPattern(pass.Fset, node, checkBytesCompareRn, m.State))
     59 		default:
     60 			panic(fmt.Sprintf("unexpected token %v", tok))
     61 		}
     62 		report.Report(pass, node, fmt.Sprintf("should use %sbytes.Equal(%s) instead", prefix, args), report.FilterGenerated(), report.Fixes(fix))
     63 	}
     64 	return nil, nil
     65 }