Custom analyzer which prevent using sync.Mutex as global variable

globalmutex.go

import (
	"go/ast"

	"golang.org/x/tools/go/analysis"
)

var Analyzer = &analysis.Analyzer{
	Name: "globalmutex",
	Doc:  "declare global mutex has no effect in multi-process, do not use",
	Run:  run,
}

func run(pass *analysis.Pass) (interface{}, error) {
	for _, f := range pass.Files {
		for _, decl := range f.Decls {
			if decl, ok := decl.(*ast.GenDecl); ok {
				for _, spec := range decl.Specs {
					if spec, ok := spec.(*ast.ValueSpec); ok {
						for _, name := range spec.Names {
							obj := pass.TypesInfo.Defs[name]
							if obj == nil {
								continue
							}
							if obj.Type().String() == "sync.Mutex" || obj.Type().String() == "*sync.Mutex" {
								pass.Report(analysis.Diagnostic{
									Pos:            name.Pos(),
									End:            0,
									Category:       "",
									Message:        "do not use mutex in global scope, it doesn't supported in multi-process and parallel test",
									SuggestedFixes: nil,
									Related:        nil,
								})
							}
						}
					}
				}
			}
		}
	}
	return nil, nil
}