diff --git a/encoding/protojson/decode_test.go b/encoding/protojson/decode_test.go
index e5385f4..0d3d312 100644
--- a/encoding/protojson/decode_test.go
+++ b/encoding/protojson/decode_test.go
@@ -10,7 +10,6 @@
 
 	"google.golang.org/protobuf/encoding/protojson"
 	"google.golang.org/protobuf/internal/flags"
-	pimpl "google.golang.org/protobuf/internal/impl"
 	"google.golang.org/protobuf/proto"
 	preg "google.golang.org/protobuf/reflect/protoregistry"
 
@@ -1899,10 +1898,7 @@
 		inputText:    `{}`,
 		wantMessage:  &anypb.Any{},
 	}, {
-		desc: "Any with non-custom message",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:         "Any with non-custom message",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "foo/pb2.Nested",
@@ -1928,24 +1924,18 @@
 			}
 		}(),
 	}, {
-		desc: "Any with empty embedded message",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:         "Any with empty embedded message",
 		inputMessage: &anypb.Any{},
 		inputText:    `{"@type": "foo/pb2.Nested"}`,
 		wantMessage:  &anypb.Any{TypeUrl: "foo/pb2.Nested"},
 	}, {
 		desc:         "Any without registered type",
-		umo:          protojson.UnmarshalOptions{Resolver: preg.NewTypes()},
+		umo:          protojson.UnmarshalOptions{Resolver: new(preg.Types)},
 		inputMessage: &anypb.Any{},
 		inputText:    `{"@type": "foo/pb2.Nested"}`,
 		wantErr:      true,
 	}, {
-		desc: "Any with missing required",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.PartialRequired{})),
-		},
+		desc:         "Any with missing required",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "pb2.PartialRequired",
@@ -1971,7 +1961,6 @@
 		desc: "Any with partial required and AllowPartial",
 		umo: protojson.UnmarshalOptions{
 			AllowPartial: true,
-			Resolver:     preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.PartialRequired{})),
 		},
 		inputMessage: &anypb.Any{},
 		inputText: `{
@@ -1995,10 +1984,7 @@
 			}
 		}(),
 	}, {
-		desc: "Any with invalid UTF8",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:         "Any with invalid UTF8",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "optString": "` + "abc\xff" + `",
@@ -2006,10 +1992,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with BoolValue",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.BoolValue{})),
-		},
+		desc:         "Any with BoolValue",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "type.googleapis.com/google.protobuf.BoolValue",
@@ -2027,10 +2010,7 @@
 			}
 		}(),
 	}, {
-		desc: "Any with Empty",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&emptypb.Empty{})),
-		},
+		desc:         "Any with Empty",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "value": {},
@@ -2040,20 +2020,14 @@
 			TypeUrl: "type.googleapis.com/google.protobuf.Empty",
 		},
 	}, {
-		desc: "Any with missing Empty",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&emptypb.Empty{})),
-		},
+		desc:         "Any with missing Empty",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "type.googleapis.com/google.protobuf.Empty"
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with StringValue containing invalid UTF8",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.StringValue{})),
-		},
+		desc:         "Any with StringValue containing invalid UTF8",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "google.protobuf.StringValue",
@@ -2061,10 +2035,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with Int64Value",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.Int64Value{})),
-		},
+		desc:         "Any with Int64Value",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "google.protobuf.Int64Value",
@@ -2082,10 +2053,7 @@
 			}
 		}(),
 	}, {
-		desc: "Any with invalid Int64Value",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.Int64Value{})),
-		},
+		desc:         "Any with invalid Int64Value",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "google.protobuf.Int64Value",
@@ -2093,10 +2061,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with invalid UInt64Value",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.UInt64Value{})),
-		},
+		desc:         "Any with invalid UInt64Value",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "google.protobuf.UInt64Value",
@@ -2104,10 +2069,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with Duration",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&durationpb.Duration{})),
-		},
+		desc:         "Any with Duration",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "type.googleapis.com/google.protobuf.Duration",
@@ -2125,10 +2087,7 @@
 			}
 		}(),
 	}, {
-		desc: "Any with Value of StringValue",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&structpb.Value{})),
-		},
+		desc:         "Any with Value of StringValue",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "google.protobuf.Value",
@@ -2136,10 +2095,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with Value of NullValue",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&structpb.Value{})),
-		},
+		desc:         "Any with Value of NullValue",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "google.protobuf.Value",
@@ -2157,16 +2113,7 @@
 			}
 		}(),
 	}, {
-		desc: "Any with Struct",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(
-				pimpl.Export{}.MessageTypeOf(&structpb.Struct{}),
-				pimpl.Export{}.MessageTypeOf(&structpb.Value{}),
-				pimpl.Export{}.MessageTypeOf(&wrapperspb.BoolValue{}),
-				pimpl.Export{}.EnumTypeOf(structpb.NullValue_NULL_VALUE),
-				pimpl.Export{}.MessageTypeOf(&wrapperspb.StringValue{}),
-			),
-		},
+		desc:         "Any with Struct",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "google.protobuf.Struct",
@@ -2221,13 +2168,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with duplicate @type",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(
-				pimpl.Export{}.MessageTypeOf(&pb2.Nested{}),
-				pimpl.Export{}.MessageTypeOf(&wrapperspb.StringValue{}),
-			),
-		},
+		desc:         "Any with duplicate @type",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "google.protobuf.StringValue",
@@ -2236,10 +2177,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with duplicate value",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.StringValue{})),
-		},
+		desc:         "Any with duplicate value",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "google.protobuf.StringValue",
@@ -2248,10 +2186,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with unknown field",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:         "Any with unknown field",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "pb2.Nested",
@@ -2260,14 +2195,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "Any with embedded type containing Any",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(
-				pimpl.Export{}.MessageTypeOf(&pb2.KnownTypes{}),
-				pimpl.Export{}.MessageTypeOf(&anypb.Any{}),
-				pimpl.Export{}.MessageTypeOf(&wrapperspb.StringValue{}),
-			),
-		},
+		desc:         "Any with embedded type containing Any",
 		inputMessage: &anypb.Any{},
 		inputText: `{
   "@type": "pb2.KnownTypes",
@@ -2278,10 +2206,7 @@
 }`,
 		wantErr: true,
 	}, {
-		desc: "well known types as field values",
-		umo: protojson.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&emptypb.Empty{})),
-		},
+		desc:         "well known types as field values",
 		inputMessage: &pb2.KnownTypes{},
 		inputText: `{
   "optBool": false,
@@ -2435,7 +2360,6 @@
 		desc: "DiscardUnknown: Any",
 		umo: protojson.UnmarshalOptions{
 			DiscardUnknown: true,
-			Resolver:       preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
 		},
 		inputMessage: &anypb.Any{},
 		inputText: `{
@@ -2449,7 +2373,6 @@
 		desc: "DiscardUnknown: Any with Empty",
 		umo: protojson.UnmarshalOptions{
 			DiscardUnknown: true,
-			Resolver:       preg.NewTypes(pimpl.Export{}.MessageTypeOf(&emptypb.Empty{})),
 		},
 		inputMessage: &anypb.Any{},
 		inputText: `{
diff --git a/encoding/protojson/encode_test.go b/encoding/protojson/encode_test.go
index 38e60e7..9ee9f25 100644
--- a/encoding/protojson/encode_test.go
+++ b/encoding/protojson/encode_test.go
@@ -14,7 +14,6 @@
 	"google.golang.org/protobuf/internal/detrand"
 	"google.golang.org/protobuf/internal/encoding/pack"
 	"google.golang.org/protobuf/internal/flags"
-	pimpl "google.golang.org/protobuf/internal/impl"
 	"google.golang.org/protobuf/proto"
 	preg "google.golang.org/protobuf/reflect/protoregistry"
 
@@ -1492,9 +1491,6 @@
 		want:  `{}`,
 	}, {
 		desc: "Any with non-custom message",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
 		input: func() proto.Message {
 			m := &pb2.Nested{
 				OptString: proto.String("embedded inside Any"),
@@ -1519,24 +1515,18 @@
   }
 }`,
 	}, {
-		desc: "Any with empty embedded message",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:  "Any with empty embedded message",
 		input: &anypb.Any{TypeUrl: "foo/pb2.Nested"},
 		want: `{
   "@type": "foo/pb2.Nested"
 }`,
 	}, {
 		desc:    "Any without registered type",
-		mo:      protojson.MarshalOptions{Resolver: preg.NewTypes()},
+		mo:      protojson.MarshalOptions{Resolver: new(preg.Types)},
 		input:   &anypb.Any{TypeUrl: "foo/pb2.Nested"},
 		wantErr: true,
 	}, {
 		desc: "Any with missing required",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.PartialRequired{})),
-		},
 		input: func() proto.Message {
 			m := &pb2.PartialRequired{
 				OptString: proto.String("embedded inside Any"),
@@ -1561,7 +1551,6 @@
 		desc: "Any with partial required and AllowPartial",
 		mo: protojson.MarshalOptions{
 			AllowPartial: true,
-			Resolver:     preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.PartialRequired{})),
 		},
 		input: func() proto.Message {
 			m := &pb2.PartialRequired{
@@ -1585,9 +1574,6 @@
 }`,
 	}, {
 		desc: "Any with invalid UTF8",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
 		input: func() proto.Message {
 			m := &pb2.Nested{
 				OptString: proto.String("abc\xff"),
@@ -1604,9 +1590,6 @@
 		wantErr: true,
 	}, {
 		desc: "Any with invalid value",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
 		input: &anypb.Any{
 			TypeUrl: "foo/pb2.Nested",
 			Value:   []byte("\x80"),
@@ -1614,9 +1597,6 @@
 		wantErr: true,
 	}, {
 		desc: "Any with BoolValue",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.BoolValue{})),
-		},
 		input: func() proto.Message {
 			m := &wrapperspb.BoolValue{Value: true}
 			b, err := proto.MarshalOptions{Deterministic: true}.Marshal(m)
@@ -1634,9 +1614,6 @@
 }`,
 	}, {
 		desc: "Any with Empty",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&emptypb.Empty{})),
-		},
 		input: func() proto.Message {
 			m := &emptypb.Empty{}
 			b, err := proto.MarshalOptions{Deterministic: true}.Marshal(m)
@@ -1654,9 +1631,6 @@
 }`,
 	}, {
 		desc: "Any with StringValue containing invalid UTF8",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.StringValue{})),
-		},
 		input: func() proto.Message {
 			m := &wrapperspb.StringValue{Value: "abcd"}
 			b, err := proto.MarshalOptions{Deterministic: true}.Marshal(m)
@@ -1671,9 +1645,6 @@
 		wantErr: true,
 	}, {
 		desc: "Any with Int64Value",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.Int64Value{})),
-		},
 		input: func() proto.Message {
 			m := &wrapperspb.Int64Value{Value: 42}
 			b, err := proto.MarshalOptions{Deterministic: true}.Marshal(m)
@@ -1691,9 +1662,6 @@
 }`,
 	}, {
 		desc: "Any with Duration",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&durationpb.Duration{})),
-		},
 		input: func() proto.Message {
 			m := &durationpb.Duration{}
 			b, err := proto.MarshalOptions{Deterministic: true}.Marshal(m)
@@ -1711,9 +1679,6 @@
 }`,
 	}, {
 		desc: "Any with empty Value",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&structpb.Value{})),
-		},
 		input: func() proto.Message {
 			m := &structpb.Value{}
 			b, err := proto.Marshal(m)
@@ -1728,9 +1693,6 @@
 		wantErr: true,
 	}, {
 		desc: "Any with Value of StringValue",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&structpb.Value{})),
-		},
 		input: func() proto.Message {
 			m := &structpb.Value{Kind: &structpb.Value_StringValue{"abcd"}}
 			b, err := proto.MarshalOptions{Deterministic: true}.Marshal(m)
@@ -1745,9 +1707,6 @@
 		wantErr: true,
 	}, {
 		desc: "Any with Value of NullValue",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&structpb.Value{})),
-		},
 		input: func() proto.Message {
 			m := &structpb.Value{Kind: &structpb.Value_NullValue{}}
 			b, err := proto.MarshalOptions{Deterministic: true}.Marshal(m)
@@ -1765,15 +1724,6 @@
 }`,
 	}, {
 		desc: "Any with Struct",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(
-				pimpl.Export{}.MessageTypeOf(&structpb.Struct{}),
-				pimpl.Export{}.MessageTypeOf(&structpb.Value{}),
-				pimpl.Export{}.MessageTypeOf(&wrapperspb.BoolValue{}),
-				pimpl.Export{}.EnumTypeOf(structpb.NullValue_NULL_VALUE),
-				pimpl.Export{}.MessageTypeOf(&wrapperspb.StringValue{}),
-			),
-		},
 		input: func() proto.Message {
 			m := &structpb.Struct{
 				Fields: map[string]*structpb.Value{
@@ -1813,9 +1763,6 @@
 }`,
 	}, {
 		desc: "Any with missing type_url",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&wrapperspb.BoolValue{})),
-		},
 		input: func() proto.Message {
 			m := &wrapperspb.BoolValue{Value: true}
 			b, err := proto.MarshalOptions{Deterministic: true}.Marshal(m)
@@ -1829,9 +1776,6 @@
 		wantErr: true,
 	}, {
 		desc: "well known types as field values",
-		mo: protojson.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&emptypb.Empty{})),
-		},
 		input: &pb2.KnownTypes{
 			OptBool:      &wrapperspb.BoolValue{Value: false},
 			OptInt32:     &wrapperspb.Int32Value{Value: 42},
diff --git a/encoding/prototext/decode_test.go b/encoding/prototext/decode_test.go
index c9df319..03ba552 100644
--- a/encoding/prototext/decode_test.go
+++ b/encoding/prototext/decode_test.go
@@ -10,7 +10,6 @@
 
 	"google.golang.org/protobuf/encoding/prototext"
 	"google.golang.org/protobuf/internal/flags"
-	pimpl "google.golang.org/protobuf/internal/impl"
 	"google.golang.org/protobuf/proto"
 	preg "google.golang.org/protobuf/reflect/protoregistry"
 
@@ -1400,10 +1399,7 @@
 			Value: []byte("some bytes"),
 		},
 	}, {
-		desc: "Any expanded",
-		umo: prototext.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:         "Any expanded",
 		inputMessage: &anypb.Any{},
 		inputText: `
 [foobar/pb2.Nested]: {
@@ -1430,20 +1426,14 @@
 			}
 		}(),
 	}, {
-		desc: "Any expanded with empty value",
-		umo: prototext.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:         "Any expanded with empty value",
 		inputMessage: &anypb.Any{},
 		inputText:    `[foo.com/pb2.Nested]: {}`,
 		wantMessage: &anypb.Any{
 			TypeUrl: "foo.com/pb2.Nested",
 		},
 	}, {
-		desc: "Any expanded with missing required",
-		umo: prototext.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.PartialRequired{})),
-		},
+		desc:         "Any expanded with missing required",
 		inputMessage: &anypb.Any{},
 		inputText: `
 [pb2.PartialRequired]: {
@@ -1467,10 +1457,7 @@
 			}
 		}(),
 	}, {
-		desc: "Any with invalid UTF-8",
-		umo: prototext.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb3.Nested{})),
-		},
+		desc:         "Any with invalid UTF-8",
 		inputMessage: &anypb.Any{},
 		inputText: `
 [pb3.Nested]: {
@@ -1480,23 +1467,17 @@
 		wantErr: true,
 	}, {
 		desc:         "Any expanded with unregistered type",
-		umo:          prototext.UnmarshalOptions{Resolver: preg.NewTypes()},
+		umo:          prototext.UnmarshalOptions{Resolver: new(preg.Types)},
 		inputMessage: &anypb.Any{},
 		inputText:    `[SomeMessage]: {}`,
 		wantErr:      true,
 	}, {
-		desc: "Any expanded with invalid value",
-		umo: prototext.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:         "Any expanded with invalid value",
 		inputMessage: &anypb.Any{},
 		inputText:    `[pb2.Nested]: 123`,
 		wantErr:      true,
 	}, {
-		desc: "Any expanded with unknown fields",
-		umo: prototext.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:         "Any expanded with unknown fields",
 		inputMessage: &anypb.Any{},
 		inputText: `
 [pb2.Nested]: {}
@@ -1504,10 +1485,7 @@
 `,
 		wantErr: true,
 	}, {
-		desc: "Any contains expanded and unexpanded fields",
-		umo: prototext.UnmarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
+		desc:         "Any contains expanded and unexpanded fields",
 		inputMessage: &anypb.Any{},
 		inputText: `
 [pb2.Nested]: {}
diff --git a/encoding/prototext/encode_test.go b/encoding/prototext/encode_test.go
index 68ceb45..ec5a225 100644
--- a/encoding/prototext/encode_test.go
+++ b/encoding/prototext/encode_test.go
@@ -13,7 +13,6 @@
 	"google.golang.org/protobuf/internal/detrand"
 	"google.golang.org/protobuf/internal/encoding/pack"
 	"google.golang.org/protobuf/internal/flags"
-	pimpl "google.golang.org/protobuf/internal/impl"
 	"google.golang.org/protobuf/proto"
 	preg "google.golang.org/protobuf/reflect/protoregistry"
 
@@ -1130,7 +1129,7 @@
 	}, {
 		desc: "Any not expanded",
 		mo: prototext.MarshalOptions{
-			Resolver: preg.NewTypes(),
+			Resolver: new(preg.Types),
 		},
 		input: func() proto.Message {
 			m := &pb2.Nested{
@@ -1153,9 +1152,6 @@
 `,
 	}, {
 		desc: "Any expanded",
-		mo: prototext.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
 		input: func() proto.Message {
 			m := &pb2.Nested{
 				OptString: proto.String("embedded inside Any"),
@@ -1181,9 +1177,6 @@
 `,
 	}, {
 		desc: "Any expanded with missing required",
-		mo: prototext.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.PartialRequired{})),
-		},
 		input: func() proto.Message {
 			m := &pb2.PartialRequired{
 				OptString: proto.String("embedded inside Any"),
@@ -1206,9 +1199,6 @@
 `,
 	}, {
 		desc: "Any with invalid value",
-		mo: prototext.MarshalOptions{
-			Resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
-		},
 		input: &anypb.Any{
 			TypeUrl: "foo/pb2.Nested",
 			Value:   []byte("\x80"),
diff --git a/encoding/prototext/other_test.go b/encoding/prototext/other_test.go
index 3ffa071..0ae4ba6 100644
--- a/encoding/prototext/other_test.go
+++ b/encoding/prototext/other_test.go
@@ -8,8 +8,6 @@
 	"testing"
 
 	"google.golang.org/protobuf/encoding/prototext"
-	"google.golang.org/protobuf/internal/impl"
-	pimpl "google.golang.org/protobuf/internal/impl"
 	"google.golang.org/protobuf/proto"
 	preg "google.golang.org/protobuf/reflect/protoregistry"
 
@@ -151,7 +149,7 @@
 		},
 	}, {
 		desc:     "Any field without registered type",
-		resolver: preg.NewTypes(),
+		resolver: new(preg.Types),
 		message: func() proto.Message {
 			m := &pb2.Nested{
 				OptString: proto.String("embedded inside Any"),
@@ -171,8 +169,7 @@
 			}
 		}(),
 	}, {
-		desc:     "Any field with registered type",
-		resolver: preg.NewTypes(pimpl.Export{}.MessageTypeOf(&pb2.Nested{})),
+		desc: "Any field with registered type",
 		message: func() *pb2.KnownTypes {
 			m := &pb2.Nested{
 				OptString: proto.String("embedded inside Any"),
@@ -193,11 +190,6 @@
 		}(),
 	}, {
 		desc: "Any field containing Any message",
-		resolver: func() *preg.Types {
-			mt1 := impl.Export{}.MessageTypeOf(&pb2.Nested{})
-			mt2 := impl.Export{}.MessageTypeOf(&anypb.Any{})
-			return preg.NewTypes(mt1, mt2)
-		}(),
 		message: func() *pb2.KnownTypes {
 			m1 := &pb2.Nested{
 				OptString: proto.String("message inside Any of another Any field"),