Add allowed-expressions flag

checknoglobals/check_no_globals.go

@@ -1,6 +1,7 @@
 package checknoglobals
 
 import (
+	"flag"
 	"fmt"
 	"go/ast"
 	"go/token"
@@ -18,6 +19,10 @@ type allowedExpression struct {
 	SelName string
 }
 
+type config struct {
+	AllowedExpression []allowedExpression
+}
+
 const Doc = `check that no global variables exist
 
 This analyzer checks for global variables and errors on any found.
@@ -36,40 +41,46 @@ func Analyzer() *analysis.Analyzer {
 		Name:             "gochecknoglobals",
 		Doc:              Doc,
 		Run:              checkNoGlobals,
+		Flags:            options(),
 		RunDespiteErrors: true,
 	}
 }
 
-func isAllowed(cm ast.CommentMap, v ast.Node, ti *types.Info) bool {
+func options() flag.FlagSet {
+	options := flag.NewFlagSet("", flag.ExitOnError)
+	options.String(
+		"allowed-expressions", "",
+		"comma separated list of expressions to exclude from analysis. Ex. regex.MustCompile,promauto.NewHistorgamVec",
+	)
+	return *options
+}
+
+func isAllowed(conf *config, cm ast.CommentMap, v ast.Node, ti *types.Info) bool {
 	switch i := v.(type) {
 	case *ast.GenDecl:
 		return hasEmbedComment(cm, i)
 	case *ast.Ident:
 		return i.Name == "_" || i.Name == "version" || isError(i, ti) || identHasEmbedComment(cm, i)
 	case *ast.CallExpr:
 		if expr, ok := i.Fun.(*ast.SelectorExpr); ok {
-			return isAllowedSelectorExpression(expr)
+			return isAllowedSelectorExpression(conf, expr)
 		}
 	case *ast.CompositeLit:
 		if expr, ok := i.Type.(*ast.SelectorExpr); ok {
-			return isAllowedSelectorExpression(expr)
+			return isAllowedSelectorExpression(conf, expr)
 		}
 	}
 
 	return false
 }
 
-func isAllowedSelectorExpression(v *ast.SelectorExpr) bool {
+func isAllowedSelectorExpression(conf *config, v *ast.SelectorExpr) bool {
 	x, ok := v.X.(*ast.Ident)
 	if !ok {
 		return false
 	}
 
-	allowList := []allowedExpression{
-		{Name: "regexp", SelName: "MustCompile"},
-	}
-
-	for _, i := range allowList {
+	for _, i := range conf.AllowedExpression {
 		if x.Name == i.Name && v.Sel.Name == i.SelName {
 			return true
 		}
@@ -128,7 +139,30 @@ func hasEmbedComment(cm ast.CommentMap, n ast.Node) bool {
 	return false
 }
 
+func parseAllowedExpressions(s string) []allowedExpression {
+	exprs := []allowedExpression{}
+	for _, str := range strings.Split(s, ",") {
+		name, sel, found := strings.Cut(str, ".")
+		if found {
+			exprs = append(exprs, allowedExpression{
+				Name:    name,
+				SelName: sel,
+			})
+		}
+	}
+	return exprs
+}
+
 func checkNoGlobals(pass *analysis.Pass) (interface{}, error) {
+	conf := &config{
+		AllowedExpression: []allowedExpression{
+			{Name: "regexp", SelName: "MustCompile"},
+		},
+	}
+	if f := pass.Analyzer.Flags.Lookup("allowed-expressions"); f != nil {
+		conf.AllowedExpression = parseAllowedExpressions(f.Value.String())
+	}
+
 	for _, file := range pass.Files {
 		filename := pass.Fset.Position(file.Pos()).Filename
 		if !strings.HasSuffix(filename, ".go") {
@@ -145,15 +179,15 @@ func checkNoGlobals(pass *analysis.Pass) (interface{}, error) {
 			if genDecl.Tok != token.VAR {
 				continue
 			}
-			if isAllowed(fileCommentMap, genDecl, pass.TypesInfo) {
+			if isAllowed(conf, fileCommentMap, genDecl, pass.TypesInfo) {
 				continue
 			}
 			for _, spec := range genDecl.Specs {
 				valueSpec := spec.(*ast.ValueSpec)
 				onlyAllowedValues := false
 
 				for _, vn := range valueSpec.Values {
-					if isAllowed(fileCommentMap, vn, pass.TypesInfo) {
+					if isAllowed(conf, fileCommentMap, vn, pass.TypesInfo) {
 						onlyAllowedValues = true
 						continue
 					}
@@ -167,7 +201,7 @@ func checkNoGlobals(pass *analysis.Pass) (interface{}, error) {
 				}
 
 				for _, vn := range valueSpec.Names {
-					if isAllowed(fileCommentMap, vn, pass.TypesInfo) {
+					if isAllowed(conf, fileCommentMap, vn, pass.TypesInfo) {
 						continue
 					}
 

checknoglobals/check_no_globals_test.go

@@ -24,6 +24,34 @@ func TestCheckNoGlobals(t *testing.T) {
 	}
 }
 
+func TestCheckNoGlobalsAllowedExpressions(t *testing.T) {
+	testdata := analysistest.TestData()
+	flags := flag.NewFlagSet("", flag.ExitOnError)
+	flags.Bool("t", true, "")
+	flags.String("allowed-expressions", "", "")
+
+	analyzer := Analyzer()
+	analyzer.Flags = *flags
+
+	dir := "12"
+	t.Run(dir, func(t *testing.T) {
+		analyzer.Flags.Set("allowed-expressions", "template.Must,sync.Once")
+
+		t.Run(dir, func(t *testing.T) {
+			analysistest.Run(t, testdata, analyzer, dir)
+		})
+	})
+
+	dir = "13"
+	t.Run(dir, func(t *testing.T) {
+		analyzer.Flags.Set("allowed-expressions", "invalid.,expression,http. Client")
+
+		t.Run(dir, func(t *testing.T) {
+			analysistest.Run(t, testdata, analyzer, dir)
+		})
+	})
+}
+
 func BenchmarkRun(b *testing.B) {
 	analyzer := Analyzer()
 	flags := flag.NewFlagSet("", flag.ExitOnError)

checknoglobals/testdata/src/12/code.go

@@ -0,0 +1,15 @@
+package code
+
+import (
+	"html/template"
+	"net/http"
+	"sync"
+)
+
+// HTMLTemplate is excluded by the flag, so should be OK
+var HTMLTemplate = template.Must(template.New("").Parse(""))
+
+// sync.Once is excluded by the flag, so should be OK
+var once = sync.Once{}
+
+var HTTPClient = http.Client{} // want "HTTPClient is a global variable"

checknoglobals/testdata/src/13/code.go

@@ -0,0 +1,7 @@
+package code
+
+import (
+	"net/http"
+)
+
+var HTTPClient = http.Client{} // want "HTTPClient is a global variable"

go.mod

@@ -1,5 +1,10 @@
 module 4d63.com/gochecknoglobals
 
-go 1.15
+go 1.18
 
 require golang.org/x/tools v0.5.0
+
+require (
+	golang.org/x/mod v0.7.0 // indirect
+	golang.org/x/sys v0.4.0 // indirect
+)

go.sum

@@ -1,34 +1,7 @@
-github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
-golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.7.0 h1:LapD9S96VoQRhi/GrNTqeBJFrUjs5UHCAtTlgwA5oZA=
 golang.org/x/mod v0.7.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
-golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
-golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
-golang.org/x/net v0.5.0/go.mod h1:DivGGAXEgPSlEBzxGzZI+ZLohi+xUj054jfeKui00ws=
-golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
-golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.4.0 h1:Zr2JFtRQNX3BCZ8YtxRE9hNJYC8J6I1MVbMg6owUp18=
 golang.org/x/sys v0.4.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
-golang.org/x/term v0.4.0/go.mod h1:9P2UbLfCdcvo3p/nzKvsmas4TnlujnuoV9hGgYzW1lQ=
-golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
-golang.org/x/text v0.6.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
-golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
-golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
 golang.org/x/tools v0.5.0 h1:+bSpV5HIeWkuvgaMfI3UmKRThoTA5ODJTUd8T17NO+4=
 golang.org/x/tools v0.5.0/go.mod h1:N+Kgy78s5I24c24dU8OfWNEotWjutIs8SnJvn5IDq+k=
-golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=