sa4028.go raw

   1  package sa4028
   2  
   3  import (
   4  	"go/ast"
   5  
   6  	"honnef.co/go/tools/analysis/code"
   7  	"honnef.co/go/tools/analysis/lint"
   8  	"honnef.co/go/tools/analysis/report"
   9  	"honnef.co/go/tools/pattern"
  10  
  11  	"golang.org/x/tools/go/analysis"
  12  	"golang.org/x/tools/go/analysis/passes/inspect"
  13  )
  14  
  15  var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
  16  	Analyzer: &analysis.Analyzer{
  17  		Name:     "SA4028",
  18  		Run:      run,
  19  		Requires: []*analysis.Analyzer{inspect.Analyzer},
  20  	},
  21  	Doc: &lint.RawDocumentation{
  22  		Title:    `\'x % 1\' is always zero`,
  23  		Since:    "2022.1",
  24  		Severity: lint.SeverityWarning,
  25  		MergeIf:  lint.MergeIfAny, // MergeIfAny if we only flag literals, not named constants
  26  	},
  27  })
  28  
  29  var Analyzer = SCAnalyzer.Analyzer
  30  
  31  var moduloOneQ = pattern.MustParse(`(BinaryExpr _ "%" (IntegerLiteral "1"))`)
  32  
  33  func run(pass *analysis.Pass) (interface{}, error) {
  34  	fn := func(node ast.Node) {
  35  		_, ok := code.Match(pass, moduloOneQ, node)
  36  		if !ok {
  37  			return
  38  		}
  39  		report.Report(pass, node, "x % 1 is always zero")
  40  	}
  41  	code.Preorder(pass, fn, (*ast.BinaryExpr)(nil))
  42  	return nil, nil
  43  }
  44