Add staticcheck tool

vendor/honnef.co/go/tools/simple/s1035/s1035.go

@@ -0,0 +1,54 @@
+package s1035
+
+import (
+	"fmt"
+	"go/ast"
+
+	"honnef.co/go/tools/analysis/code"
+	"honnef.co/go/tools/analysis/edit"
+	"honnef.co/go/tools/analysis/facts/generated"
+	"honnef.co/go/tools/analysis/lint"
+	"honnef.co/go/tools/analysis/report"
+	"honnef.co/go/tools/pattern"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
+	Analyzer: &analysis.Analyzer{
+		Name:     "S1035",
+		Run:      run,
+		Requires: append([]*analysis.Analyzer{generated.Analyzer}, code.RequiredAnalyzers...),
+	},
+	Doc: &lint.RawDocumentation{
+		Title: `Redundant call to \'net/http.CanonicalHeaderKey\' in method call on \'net/http.Header\'`,
+		Text: `
+The methods on \'net/http.Header\', namely \'Add\', \'Del\', \'Get\'
+and \'Set\', already canonicalize the given header name.`,
+		Since:   "2020.1",
+		MergeIf: lint.MergeIfAny,
+	},
+})
+
+var Analyzer = SCAnalyzer.Analyzer
+
+var query = pattern.MustParse(`
+	(CallExpr
+		(Symbol
+			callName@(Or
+				"(net/http.Header).Add"
+				"(net/http.Header).Del"
+				"(net/http.Header).Get"
+				"(net/http.Header).Set"))
+		arg@(CallExpr (Symbol "net/http.CanonicalHeaderKey") _):_)`)
+
+func run(pass *analysis.Pass) (any, error) {
+	for _, m := range code.Matches(pass, query) {
+		arg := m.State["arg"].(*ast.CallExpr)
+		report.Report(pass, m.State["arg"].(ast.Expr),
+			fmt.Sprintf("calling net/http.CanonicalHeaderKey on the 'key' argument of %s is redundant", m.State["callName"].(string)),
+			report.FilterGenerated(),
+			report.Fixes(edit.Fix("Remove call to CanonicalHeaderKey", edit.ReplaceWithNode(pass.Fset, arg, arg.Args[0]))))
+	}
+	return nil, nil
+}