feat: allow to specify Go version

README.md

@@ -47,7 +47,9 @@ go vet -vettool=(which tenv) ./...
 
 ### option
 
-The option `all` will run against whole test files (`_test.go`) regardless of method/function signatures.  
+The option `all` will run against whole test files (`_test.go`) regardless of method/function signatures.
+
+The option `go` allows to specify Go version. If the version is not empty and lower than Go 1.17 the analysis will be skipped.
 
 By default, only methods that take `*testing.T`, `*testing.B`, and `testing.TB` as arguments are checked.
 

tenv.go

@@ -2,6 +2,7 @@ package tenv
 
 import (
 	"go/ast"
+	"strconv"
 	"strings"
 
 	"golang.org/x/tools/go/analysis"
@@ -24,13 +25,22 @@ var Analyzer = &analysis.Analyzer{
 var (
 	A     = "all"
 	aflag bool
+
+	Go     = "go"
+	goflag string
 )
 
 func init() {
 	Analyzer.Flags.BoolVar(&aflag, A, false, "the all option will run against all method in test file")
+	Analyzer.Flags.StringVar(&goflag, Go, "1.17", "Go version")
 }
 
 func run(pass *analysis.Pass) (interface{}, error) {
+	if goVersionLower117(goflag) {
+		// Do nothing because T.Setenv added in go1.17
+		return nil, nil
+	}
+
 	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
 
 	nodeFilter := []ast.Node{
@@ -44,7 +54,6 @@ func run(pass *analysis.Pass) (interface{}, error) {
 			checkFuncDecl(pass, n, pass.Fset.File(n.Pos()).Name())
 		case *ast.FuncLit:
 			checkFuncLit(pass, n, pass.Fset.File(n.Pos()).Name())
-		}
 	})
 
 	return nil, nil
@@ -211,3 +220,35 @@ func checkSelectorExprTarget(typ *ast.SelectorExpr) bool {
 	targetName := x.Name + "." + typ.Sel.Name
 	return targetName == "testing.TB"
 }
+
+// goVersionLower117 returns true if version is lower than go1.17.
+// In case of any parse errors it returns false.
+func goVersionLower117(version string) bool {
+	version = strings.TrimPrefix(version, "go")
+	if version == "" {
+		return false
+	}
+
+	parts := strings.Split(version, ".")
+	if len(parts) != 2 {
+		return false
+	}
+
+	major, err := strconv.Atoi(parts[0])
+	if err != nil {
+		return false
+	}
+	if major < 1 {
+		return true
+	}
+
+	minor, err := strconv.Atoi(parts[1])
+	if err != nil {
+		return false
+	}
+	if minor < 17 {
+		return true
+	}
+
+	return false
+}

tenv_test.go

@@ -14,3 +14,10 @@ func TestAnalyzer(t *testing.T) {
 	testdata := testutil.WithModules(t, analysistest.TestData(), nil)
 	analysistest.Run(t, testdata, tenv.Analyzer, "a")
 }
+
+func TestAnalyzerGo116(t *testing.T) {
+	testdata := testutil.WithModules(t, analysistest.TestData(), nil)
+	a := tenv.Analyzer
+	a.Flags.Parse([]string{"-go", "1.16"})
+	analysistest.Run(t, testdata, a, "go116")
+}

testdata/src/go116/go.mod

@@ -0,0 +1,3 @@
+module go116
+
+go 1.16

testdata/src/go116/go116_test.go

@@ -0,0 +1,12 @@
+package go116
+
+import (
+	"os"
+	"testing"
+)
+
+func TestF(t *testing.T) {
+	os.Setenv("a", "b")        // if -go = 1.16, ""
+	err := os.Setenv("a", "b") // if -go = 1.16, ""
+	_ = err
+}