Init

internal/customvet/.gitignore

@@ -0,0 +1 @@
+/customvet

internal/customvet/checks/setval/setval.go

@@ -0,0 +1,62 @@
+package setval
+
+import (
+	"go/ast"
+	"go/token"
+	"go/types"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var Analyzer = &analysis.Analyzer{
+	Name: "setval",
+	Doc:  "find Cmder types that are missing a SetVal method",
+
+	Run: func(pass *analysis.Pass) (interface{}, error) {
+		cmderTypes := make(map[string]token.Pos)
+		typesWithSetValMethod := make(map[string]bool)
+
+		for _, file := range pass.Files {
+			for _, decl := range file.Decls {
+				funcName, receiverType := parseFuncDecl(decl, pass.TypesInfo)
+
+				switch funcName {
+				case "Result":
+					cmderTypes[receiverType] = decl.Pos()
+				case "SetVal":
+					typesWithSetValMethod[receiverType] = true
+				}
+			}
+		}
+
+		for cmder, pos := range cmderTypes {
+			if !typesWithSetValMethod[cmder] {
+				pass.Reportf(pos, "%s is missing a SetVal method", cmder)
+			}
+		}
+
+		return nil, nil
+	},
+}
+
+func parseFuncDecl(decl ast.Decl, typesInfo *types.Info) (funcName, receiverType string) {
+	funcDecl, ok := decl.(*ast.FuncDecl)
+	if !ok {
+		return "", "" // Not a function declaration.
+	}
+
+	if funcDecl.Recv == nil {
+		return "", "" // Not a method.
+	}
+
+	if len(funcDecl.Recv.List) != 1 {
+		return "", "" // Unexpected number of receiver arguments. (Can this happen?)
+	}
+
+	receiverTypeObj := typesInfo.TypeOf(funcDecl.Recv.List[0].Type)
+	if receiverTypeObj == nil {
+		return "", "" // Unable to determine the receiver type.
+	}
+
+	return funcDecl.Name.Name, receiverTypeObj.String()
+}

internal/customvet/checks/setval/setval_test.go

@@ -0,0 +1,14 @@
+package setval_test
+
+import (
+	"testing"
+
+	"golang.org/x/tools/go/analysis/analysistest"
+
+	"github.com/redis/go-redis/internal/customvet/checks/setval"
+)
+
+func Test(t *testing.T) {
+	testdata := analysistest.TestData()
+	analysistest.Run(t, testdata, setval.Analyzer, "a")
+}

internal/customvet/checks/setval/testdata/src/a/a.go

@@ -0,0 +1,29 @@
+package a
+
+type GoodCmd struct {
+	val int
+}
+
+func (c *GoodCmd) SetVal(val int) {
+	c.val = val
+}
+
+func (c *GoodCmd) Result() (int, error) {
+	return c.val, nil
+}
+
+type BadCmd struct {
+	val int
+}
+
+func (c *BadCmd) Result() (int, error) { // want "\\*a.BadCmd is missing a SetVal method"
+	return c.val, nil
+}
+
+type NotACmd struct {
+	val int
+}
+
+func (c *NotACmd) Val() int {
+	return c.val
+}

internal/customvet/go.mod

@@ -0,0 +1,10 @@
+module github.com/redis/go-redis/internal/customvet
+
+go 1.17
+
+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
+)

internal/customvet/go.sum

@@ -0,0 +1,7 @@
+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/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
+golang.org/x/sys v0.4.0 h1:Zr2JFtRQNX3BCZ8YtxRE9hNJYC8J6I1MVbMg6owUp18=
+golang.org/x/sys v0.4.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/tools v0.5.0 h1:+bSpV5HIeWkuvgaMfI3UmKRThoTA5ODJTUd8T17NO+4=
+golang.org/x/tools v0.5.0/go.mod h1:N+Kgy78s5I24c24dU8OfWNEotWjutIs8SnJvn5IDq+k=

internal/customvet/main.go

@@ -0,0 +1,13 @@
+package main
+
+import (
+	"golang.org/x/tools/go/analysis/multichecker"
+
+	"github.com/redis/go-redis/internal/customvet/checks/setval"
+)
+
+func main() {
+	multichecker.Main(
+		setval.Analyzer,
+	)
+}