Add staticcheck tool

vendor/honnef.co/go/tools/staticcheck/sa1018/sa1018.go

@@ -0,0 +1,47 @@
+package sa1018
+
+import (
+	"fmt"
+	"go/constant"
+
+	"honnef.co/go/tools/analysis/callcheck"
+	"honnef.co/go/tools/analysis/lint"
+	"honnef.co/go/tools/go/ir"
+	"honnef.co/go/tools/internal/passes/buildir"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
+	Analyzer: &analysis.Analyzer{
+		Name:     "SA1018",
+		Requires: []*analysis.Analyzer{buildir.Analyzer},
+		Run:      callcheck.Analyzer(rules),
+	},
+	Doc: &lint.RawDocumentation{
+		Title: `\'strings.Replace\' called with \'n == 0\', which does nothing`,
+		Text: `With \'n == 0\', zero instances will be replaced. To replace all
+instances, use a negative number, or use \'strings.ReplaceAll\'.`,
+		Since:    "2017.1",
+		Severity: lint.SeverityWarning,
+		MergeIf:  lint.MergeIfAny, // MergeIfAny if we only flag literals, not named constants
+	},
+})
+
+var Analyzer = SCAnalyzer.Analyzer
+
+var rules = map[string]callcheck.Check{
+	"strings.Replace": check("strings.Replace", 3),
+	"bytes.Replace":   check("bytes.Replace", 3),
+}
+
+func check(name string, arg int) callcheck.Check {
+	return func(call *callcheck.Call) {
+		arg := call.Args[arg]
+		if k, ok := arg.Value.Value.(*ir.Const); ok && k.Value.Kind() == constant.Int {
+			if v, ok := constant.Int64Val(k.Value); ok && v == 0 {
+				arg.Invalid(fmt.Sprintf("calling %s with n == 0 will return no results, did you mean -1?", name))
+			}
+		}
+	}
+}