support types.Alias

.github/workflows/testing.yml

@@ -12,7 +12,7 @@ jobs:
     strategy:
       matrix:
         os: [ macos-latest, ubuntu-latest]
-        go_vers: ['1.21', '1.22']
+        go_vers: ['1.21', '1.22', '1.23']
     steps:
       - uses: actions/checkout@v2
         with:

pkg/generator_go123_test.go

@@ -2,9 +2,21 @@
 
 package pkg
 
-import "regexp"
+import (
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"regexp"
+)
 
 func (s *GeneratorSuite) TestReplaceTypePackagePrologueGo123() {
+	if !isTypeAliasEnabled() {
+		// "go 1.22" in go.mod makes gotypesalias=0 even when compiling with Go 1.23.
+		// Remove this when upgrading to Go 1.23 in go.mod.
+		return
+	}
+
 	expected := `package mocks
 
 import baz "github.com/vektra/mockery/v2/pkg/fixtures/example_project/baz"
@@ -22,6 +34,12 @@ import mock "github.com/stretchr/testify/mock"
 }
 
 func (s *GeneratorSuite) TestReplaceTypePackageGo123() {
+	if !isTypeAliasEnabled() {
+		// "go 1.22" in go.mod makes gotypesalias=0 even when compiling with Go 1.23.
+		// Remove this when upgrading to Go 1.23 in go.mod.
+		return
+	}
+
 	cfg := GeneratorConfig{InPackage: false}
 
 	s.checkGenerationRegexWithConfig("example_project/baz/foo.go", "Foo", cfg, []regexpExpected{
@@ -33,6 +51,12 @@ func (s *GeneratorSuite) TestReplaceTypePackageGo123() {
 }
 
 func (s *GeneratorSuite) TestReplaceTypePackageMultiplePrologueGo123() {
+	if !isTypeAliasEnabled() {
+		// "go 1.22" in go.mod makes gotypesalias=0 even when compiling with Go 1.23.
+		// Remove this when upgrading to Go 1.23 in go.mod.
+		return
+	}
+
 	expected := `package mocks
 
 import mock "github.com/stretchr/testify/mock"
@@ -52,6 +76,12 @@ import rt2 "github.com/vektra/mockery/v2/pkg/fixtures/example_project/replace_ty
 }
 
 func (s *GeneratorSuite) TestReplaceTypePackageMultipleGo123() {
+	if !isTypeAliasEnabled() {
+		// "go 1.22" in go.mod makes gotypesalias=0 even when compiling with Go 1.23.
+		// Remove this when upgrading to Go 1.23 in go.mod.
+		return
+	}
+
 	cfg := GeneratorConfig{InPackage: false}
 
 	s.checkGenerationRegexWithConfig("example_project/replace_type/rt.go", "RType", cfg, []regexpExpected{
@@ -61,3 +91,25 @@ func (s *GeneratorSuite) TestReplaceTypePackageMultipleGo123() {
 		{true, regexp.MustCompile(`func \([^\)]+\) Replace2\(f rt2\.RType2`)},
 	})
 }
+
+// isTypeAliasEnabled reports whether [NewAlias] should create [types.Alias] types.
+//
+// This function is expensive! Call it sparingly.
+// source: /go/1.23.0/libexec/src/cmd/vendor/golang.org/x/tools/internal/aliases/aliases_go122.go
+func isTypeAliasEnabled() bool {
+	// The only reliable way to compute the answer is to invoke go/types.
+	// We don't parse the GODEBUG environment variable, because
+	// (a) it's tricky to do so in a manner that is consistent
+	//     with the godebug package; in particular, a simple
+	//     substring check is not good enough. The value is a
+	//     rightmost-wins list of options. But more importantly:
+	// (b) it is impossible to detect changes to the effective
+	//     setting caused by os.Setenv("GODEBUG"), as happens in
+	//     many tests. Therefore any attempt to cache the result
+	//     is just incorrect.
+	fset := token.NewFileSet()
+	f, _ := parser.ParseFile(fset, "a.go", "package p; type A = int", 0)
+	pkg, _ := new(types.Config).Check("p", fset, []*ast.File{f}, nil)
+	_, enabled := pkg.Scope().Lookup("A").Type().(*types.Alias)
+	return enabled
+}