Add staticcheck tool

vendor/honnef.co/go/tools/stylecheck/st1016/st1016.go

@@ -0,0 +1,74 @@
+package st1016
+
+import (
+	"fmt"
+	"go/types"
+	"sort"
+	"strings"
+
+	"honnef.co/go/tools/analysis/code"
+	"honnef.co/go/tools/analysis/facts/generated"
+	"honnef.co/go/tools/analysis/lint"
+	"honnef.co/go/tools/analysis/report"
+	"honnef.co/go/tools/go/types/typeutil"
+	"honnef.co/go/tools/internal/passes/buildir"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
+	Analyzer: &analysis.Analyzer{
+		Name:     "ST1016",
+		Run:      run,
+		Requires: []*analysis.Analyzer{buildir.Analyzer, generated.Analyzer},
+	},
+	Doc: &lint.RawDocumentation{
+		Title:      `Use consistent method receiver names`,
+		Since:      "2019.1",
+		NonDefault: true,
+		MergeIf:    lint.MergeIfAny,
+	},
+})
+
+var Analyzer = SCAnalyzer.Analyzer
+
+func run(pass *analysis.Pass) (any, error) {
+	irpkg := pass.ResultOf[buildir.Analyzer].(*buildir.IR).Pkg
+	for _, m := range irpkg.Members {
+		names := map[string]int{}
+
+		var firstFn *types.Func
+		if T, ok := m.Object().(*types.TypeName); ok && !T.IsAlias() {
+			ms := typeutil.IntuitiveMethodSet(T.Type(), nil)
+			for _, sel := range ms {
+				fn := sel.Obj().(*types.Func)
+				recv := fn.Type().(*types.Signature).Recv()
+				if code.IsGenerated(pass, recv.Pos()) {
+					// Don't concern ourselves with methods in generated code
+					continue
+				}
+				if typeutil.Dereference(recv.Type()) != T.Type() {
+					// skip embedded methods
+					continue
+				}
+				if firstFn == nil {
+					firstFn = fn
+				}
+				if recv.Name() != "" && recv.Name() != "_" {
+					names[recv.Name()]++
+				}
+			}
+		}
+
+		if len(names) > 1 {
+			var seen []string
+			for name, count := range names {
+				seen = append(seen, fmt.Sprintf("%dx %q", count, name))
+			}
+			sort.Strings(seen)
+
+			report.Report(pass, firstFn, fmt.Sprintf("methods on the same type should have the same receiver name (seen %s)", strings.Join(seen, ", ")))
+		}
+	}
+	return nil, nil
+}