github.com/amarpal/go-tools@v0.0.0-20240422043104-40142f59f616/simple/s1035/s1035.go (about)

     1  package s1035
     2  
     3  import (
     4  	"fmt"
     5  	"go/ast"
     6  
     7  	"github.com/amarpal/go-tools/analysis/code"
     8  	"github.com/amarpal/go-tools/analysis/edit"
     9  	"github.com/amarpal/go-tools/analysis/facts/generated"
    10  	"github.com/amarpal/go-tools/analysis/lint"
    11  	"github.com/amarpal/go-tools/analysis/report"
    12  
    13  	"golang.org/x/tools/go/analysis"
    14  	"golang.org/x/tools/go/analysis/passes/inspect"
    15  )
    16  
    17  var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
    18  	Analyzer: &analysis.Analyzer{
    19  		Name:     "S1035",
    20  		Run:      run,
    21  		Requires: []*analysis.Analyzer{inspect.Analyzer, generated.Analyzer},
    22  	},
    23  	Doc: &lint.Documentation{
    24  		Title: `Redundant call to \'net/http.CanonicalHeaderKey\' in method call on \'net/http.Header\'`,
    25  		Text: `
    26  The methods on \'net/http.Header\', namely \'Add\', \'Del\', \'Get\'
    27  and \'Set\', already canonicalize the given header name.`,
    28  		Since:   "2020.1",
    29  		MergeIf: lint.MergeIfAny,
    30  	},
    31  })
    32  
    33  var Analyzer = SCAnalyzer.Analyzer
    34  
    35  func run(pass *analysis.Pass) (interface{}, error) {
    36  	fn := func(node ast.Node) {
    37  		call := node.(*ast.CallExpr)
    38  		callName := code.CallName(pass, call)
    39  		switch callName {
    40  		case "(net/http.Header).Add", "(net/http.Header).Del", "(net/http.Header).Get", "(net/http.Header).Set":
    41  		default:
    42  			return
    43  		}
    44  
    45  		if !code.IsCallTo(pass, call.Args[0], "net/http.CanonicalHeaderKey") {
    46  			return
    47  		}
    48  
    49  		report.Report(pass, call,
    50  			fmt.Sprintf("calling net/http.CanonicalHeaderKey on the 'key' argument of %s is redundant", callName),
    51  			report.FilterGenerated(),
    52  			report.Fixes(edit.Fix("remove call to CanonicalHeaderKey", edit.ReplaceWithNode(pass.Fset, call.Args[0], call.Args[0].(*ast.CallExpr).Args[0]))))
    53  	}
    54  	code.Preorder(pass, fn, (*ast.CallExpr)(nil))
    55  	return nil, nil
    56  }