Allow types defined as instantiated generic interfaces to generate mocks

Fixes issue #787. Allow `*ast.IndexExpr` in a `*ast.TypeSpec` to be a mock
target.

cmd/mockery.go

@@ -244,11 +244,6 @@ func (r *RootApp) Run() error {
 			log.Error().Err(err).Msg("unable to parse packages")
 			return err
 		}
-		log.Info().Msg("done parsing, loading")
-		if err := parser.Load(); err != nil {
-			log.Err(err).Msgf("failed to load parser")
-			return nil
-		}
 		log.Info().Msg("done loading, visiting interface nodes")
 		for _, iface := range parser.Interfaces() {
 			ifaceLog := log.

pkg/fixtures/instantiated_generic_interface.go

@@ -0,0 +1,7 @@
+package test
+
+type GenericInterface[M any] interface {
+	Func(arg *M) int
+}
+
+type InstantiatedGenericInterface GenericInterface[float32]

pkg/fixtures/variadic.go

@@ -5,4 +5,3 @@ type VariadicFunction = func(args1 string, args2 ...interface{}) interface{}
 type Variadic interface {
 	VariadicFunction(str string, vFunc VariadicFunction) error
 }
-

pkg/generator_test.go

@@ -40,7 +40,7 @@ func (s *GeneratorSuite) getInterfaceFromFile(interfacePath, interfaceName strin
 	)
 
 	s.Require().NoError(
-		s.parser.Load(),
+		s.parser.Load(context.Background()),
 	)
 
 	iface, err := s.parser.Find(interfaceName)

pkg/outputter_test.go

@@ -256,7 +256,7 @@ packages:
 			m.config.Config = confPath.String()
 
 			require.NoError(t, parser.ParsePackages(ctx, []string{tt.packagePath}))
-			require.NoError(t, parser.Load())
+			require.NoError(t, parser.Load(context.Background()))
 			for _, intf := range parser.Interfaces() {
 				t.Logf("generating interface: %s %s", intf.QualifiedName, intf.Name)
 				require.NoError(t, m.Generate(ctx, intf))

pkg/parse.go

@@ -16,21 +16,27 @@ import (
 	"golang.org/x/tools/go/packages"
 )
 
-type parserEntry struct {
+type fileEntry struct {
 	fileName   string
 	pkg        *packages.Package
 	syntax     *ast.File
 	interfaces []string
 }
 
+func (f *fileEntry) ParseInterfaces(ctx context.Context) {
+	nv := NewNodeVisitor(ctx)
+	ast.Walk(nv, f.syntax)
+	f.interfaces = nv.DeclaredInterfaces()
+}
+
 type packageLoadEntry struct {
 	pkgs []*packages.Package
 	err  error
 }
 
 type Parser struct {
-	entries           []*parserEntry
-	entriesByFileName map[string]*parserEntry
+	files             []*fileEntry
+	entriesByFileName map[string]*fileEntry
 	parserPackages    []*types.Package
 	conf              packages.Config
 	packageLoadCache  map[string]packageLoadEntry
@@ -52,7 +58,7 @@ func NewParser(buildTags []string) *Parser {
 	}
 	return &Parser{
 		parserPackages:    make([]*types.Package, 0),
-		entriesByFileName: map[string]*parserEntry{},
+		entriesByFileName: map[string]*fileEntry{},
 		conf:              conf,
 		packageLoadCache:  map[string]packageLoadEntry{},
 	}
@@ -86,18 +92,21 @@ func (p *Parser) ParsePackages(ctx context.Context, packageNames []string) error
 				Str("package", pkg.PkgPath).
 				Str("file", file).
 				Msgf("found file")
-			entry := parserEntry{
+			entry := fileEntry{
 				fileName: file,
 				pkg:      pkg,
 				syntax:   pkg.Syntax[fileIdx],
 			}
-			p.entries = append(p.entries, &entry)
+			entry.ParseInterfaces(ctx)
+			p.files = append(p.files, &entry)
 			p.entriesByFileName[file] = &entry
 		}
 	}
 	return nil
 }
 
+// DEPRECATED: Parse is part of the deprecated, legacy mockery behavior. This is not
+// used when the packages feature is enabled.
 func (p *Parser) Parse(ctx context.Context, path string) error {
 	// To support relative paths to mock targets w/ vendor deps, we need to provide eventual
 	// calls to build.Context.Import with an absolute path. It needs to be absolute because
@@ -164,30 +173,28 @@ func (p *Parser) Parse(ctx context.Context, path string) error {
 			if _, ok := p.entriesByFileName[f]; ok {
 				continue
 			}
-			entry := parserEntry{
+			entry := fileEntry{
 				fileName: f,
 				pkg:      pkg,
 				syntax:   pkg.Syntax[idx],
 			}
-			p.entries = append(p.entries, &entry)
+			p.files = append(p.files, &entry)
 			p.entriesByFileName[f] = &entry
 		}
 	}
 
 	return nil
 }
 
-func (p *Parser) Load() error {
-	for _, entry := range p.entries {
-		nv := NewNodeVisitor()
-		ast.Walk(nv, entry.syntax)
-		entry.interfaces = nv.DeclaredInterfaces()
+func (p *Parser) Load(ctx context.Context) error {
+	for _, entry := range p.files {
+		entry.ParseInterfaces(ctx)
 	}
 	return nil
 }
 
 func (p *Parser) Find(name string) (*Interface, error) {
-	for _, entry := range p.entries {
+	for _, entry := range p.files {
 		for _, iface := range entry.interfaces {
 			if iface == name {
 				list := p.packageInterfaces(entry.pkg.Types, entry.fileName, []string{name}, nil)
@@ -202,7 +209,7 @@ func (p *Parser) Find(name string) (*Interface, error) {
 
 func (p *Parser) Interfaces() []*Interface {
 	ifaces := make(sortableIFaceList, 0)
-	for _, entry := range p.entries {
+	for _, entry := range p.files {
 		declaredIfaces := entry.interfaces
 		ifaces = p.packageInterfaces(entry.pkg.Types, entry.fileName, declaredIfaces, ifaces)
 	}
@@ -314,12 +321,15 @@ func (s sortableIFaceList) Less(i, j int) bool {
 }
 
 type NodeVisitor struct {
-	declaredInterfaces []string
+	declaredInterfaces            []string
+	genericInstantiationInterface map[string]any
+	ctx                           context.Context
 }
 
-func NewNodeVisitor() *NodeVisitor {
+func NewNodeVisitor(ctx context.Context) *NodeVisitor {
 	return &NodeVisitor{
 		declaredInterfaces: make([]string, 0),
+		ctx:                ctx,
 	}
 }
 
@@ -328,11 +338,23 @@ func (nv *NodeVisitor) DeclaredInterfaces() []string {
 }
 
 func (nv *NodeVisitor) Visit(node ast.Node) ast.Visitor {
+	log := zerolog.Ctx(nv.ctx)
+
 	switch n := node.(type) {
 	case *ast.TypeSpec:
+		log := log.With().
+			Str("node-name", n.Name.Name).
+			Str("node-type", fmt.Sprintf("%T", n.Type)).
+			Logger()
+
 		switch n.Type.(type) {
-		case *ast.InterfaceType, *ast.FuncType:
+		case *ast.InterfaceType, *ast.FuncType, *ast.IndexExpr:
+			log.Debug().
+				Str("node-type", fmt.Sprintf("%T", n.Type)).
+				Msg("found node with acceptable type for mocking")
 			nv.declaredInterfaces = append(nv.declaredInterfaces, n.Name.Name)
+		default:
+			log.Debug().Msg("Found node with unacceptable type for mocking. Rejecting.")
 		}
 	}
 	return nv

pkg/parse_test.go

@@ -16,7 +16,7 @@ func TestFileParse(t *testing.T) {
 	err := parser.Parse(ctx, testFile)
 	assert.NoError(t, err)
 
-	err = parser.Load()
+	err = parser.Load(context.Background())
 	assert.NoError(t, err)
 
 	node, err := parser.Find("Requester")
@@ -38,7 +38,7 @@ func TestBuildTagInFilename(t *testing.T) {
 	err = parser.Parse(ctx, getFixturePath("buildtag", "filename", "iface_freebsd.go"))
 	assert.NoError(t, err)
 
-	err = parser.Load()
+	err = parser.Load(context.Background())
 	assert.NoError(t, err) // Expect "redeclared in this block" if tags aren't respected
 
 	nodes := parser.Interfaces()
@@ -60,7 +60,7 @@ func TestBuildTagInComment(t *testing.T) {
 	err = parser.Parse(ctx, getFixturePath("buildtag", "comment", "freebsd_iface.go"))
 	assert.NoError(t, err)
 
-	err = parser.Load()
+	err = parser.Load(context.Background())
 	assert.NoError(t, err) // Expect "redeclared in this block" if tags aren't respected
 
 	nodes := parser.Interfaces()
@@ -78,7 +78,7 @@ func TestCustomBuildTag(t *testing.T) {
 	err = parser.Parse(ctx, getFixturePath("buildtag", "comment", "custom2_iface.go"))
 	assert.NoError(t, err)
 
-	err = parser.Load()
+	err = parser.Load(context.Background())
 	assert.NoError(t, err) // Expect "redeclared in this block" if tags aren't respected
 
 	found := false
@@ -94,6 +94,6 @@ func TestCustomBuildTag(t *testing.T) {
 func TestParsePackages(t *testing.T) {
 	parser := NewParser([]string{})
 	require.NoError(t, parser.ParsePackages(context.Background(), []string{"github.com/vektra/mockery/v2/pkg/fixtures"}))
-	assert.NotEqual(t, 0, len(parser.entries))
+	assert.NotEqual(t, 0, len(parser.files))
 
 }