diff --git a/encoding/openapi/decode_test.go b/encoding/openapi/decode_test.go
index edf586788..6087e933d 100644
--- a/encoding/openapi/decode_test.go
+++ b/encoding/openapi/decode_test.go
@@ -39,8 +39,13 @@ import (
 	"cuelang.org/go/internal/cuetest"
 )
 
-// TestDecode reads the testdata/*.txtar files, converts the contained
-// JSON schema to CUE and compares it against the output.
+// TestDecode reads the testdata/script/*.txtar files, converts the
+// contained JSON (or YAML) schema to CUE and compares it against the
+// output.
+//
+// The first .json or .yaml file in the txtar archive (with no / in
+// the name) is used as the input. The first .cue file in the archive
+// (with no / in the name) is used as the expected output.
 //
 // Set CUE_UPDATE=1 to update test files with the corresponding output.
 func TestDecode(t *testing.T) {
@@ -65,18 +70,29 @@ func TestDecode(t *testing.T) {
 			outIndex := -1
 
 			for i, f := range a.Files {
+				if strings.Contains(f.Name, "/") {
+					continue
+				}
 				switch path.Ext(f.Name) {
 				case ".json":
-					var inExpr ast.Expr
-					inExpr, err = json.Extract(f.Name, f.Data)
-					inFile = internal.ToFile(inExpr)
+					if inFile == nil {
+						var inExpr ast.Expr
+						inExpr, err = json.Extract(f.Name, f.Data)
+						inFile = internal.ToFile(inExpr)
+					}
 				case ".yaml":
-					inFile, err = yaml.Extract(f.Name, f.Data)
+					if inFile == nil {
+						inFile, err = yaml.Extract(f.Name, f.Data)
+					}
 				case ".cue":
-					out = f.Data
-					outIndex = i
+					if out == nil {
+						out = f.Data
+						outIndex = i
+					}
 				case ".err":
-					errout = f.Data
+					if errout == nil {
+						errout = f.Data
+					}
 				}
 			}
 			if err != nil {
diff --git a/encoding/openapi/openapi_test.go b/encoding/openapi/openapi_test.go
index f2bd4d372..036e3e238 100644
--- a/encoding/openapi/openapi_test.go
+++ b/encoding/openapi/openapi_test.go
@@ -29,98 +29,90 @@ import (
 	"cuelang.org/go/cue/errors"
 	"cuelang.org/go/cue/load"
 	"cuelang.org/go/encoding/openapi"
+	"cuelang.org/go/internal/cuetdtest"
 	"cuelang.org/go/internal/cuetest"
+	"cuelang.org/go/internal/cuetxtar"
 )
 
+var (
+	matrix = cuetdtest.FullMatrix
+)
+
+func TestGenerateOpenAPI(t *testing.T) {
+	test := cuetxtar.TxTarTest{
+		Root:   "./testdata",
+		Name:   t.Name(),
+		Matrix: matrix,
+	}
+
+	test.Run(t, func(t *cuetxtar.Test) {
+		if t.HasTag("skip-" + t.Name()) {
+			t.Skip()
+		}
+
+		a := t.Instance()
+		ctx := t.CueContext()
+		v := ctx.BuildInstance(a)
+
+		if err := v.Err(); err != nil {
+			t.Fatal(errors.Details(err, nil))
+		}
+
+		config := openapi.Config{}
+		if t.HasTag("ExpandReferences") {
+			config.ExpandReferences = true
+		}
+		if filter, ok := t.Value("FieldFilter"); ok {
+			config.FieldFilter = filter
+		}
+		if version, ok := t.Value("Version"); ok {
+			config.Version = version
+		}
+
+		expectedErr, shouldErr := t.Value("ExpectError")
+		b, err := openapi.Gen(v, &config)
+		if err != nil {
+			details := errors.Details(err, nil)
+			if !shouldErr || !strings.Contains(details, expectedErr) {
+				t.Fatal("unexpected error:", details)
+			}
+			return
+		}
+
+		if shouldErr {
+			t.Fatal("unexpected success")
+		} else {
+			_, err := openapi.Generate(v, &config)
+			if err != nil {
+				t.Fatal(err)
+			}
+		}
+
+		var out = &bytes.Buffer{}
+		err = json.Indent(out, b, "", "   ")
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		w := t.Writer("out.json")
+		jsonStr := out.String()
+		jsonStr = strings.TrimSpace(jsonStr) + "\n"
+		_, err = w.Write([]byte(jsonStr))
+		if err != nil {
+			t.Fatal(err)
+		}
+	})
+}
+
 func TestParseDefinitions(t *testing.T) {
 	info := struct {
 		Title   string `json:"title"`
 		Version string `json:"version"`
 	}{"test", "v1"}
-	defaultConfig := &openapi.Config{}
-	resolveRefs := &openapi.Config{Info: info, ExpandReferences: true}
-
 	testCases := []struct {
 		in, out string
-		variant string
 		config  *openapi.Config
-		err     string
 	}{{
-		in:     "structural.cue",
-		out:    "structural.json",
-		config: resolveRefs,
-	}, {
-		in:  "protobuf.cue",
-		out: "protobuf.json",
-		config: &openapi.Config{
-			Info:             info,
-			ExpandReferences: true,
-		},
-	}, {
-		in:     "nested.cue",
-		out:    "nested.json",
-		config: defaultConfig,
-	}, {
-		in:     "simple.cue",
-		out:    "simple.json",
-		config: resolveRefs,
-	}, {
-		in:     "simple.cue",
-		out:    "simple-filter.json",
-		config: &openapi.Config{Info: info, FieldFilter: "min.*|max.*"},
-	}, {
-		in:     "array.cue",
-		out:    "array.json",
-		config: defaultConfig,
-	}, {
-		in:     "enum.cue",
-		out:    "enum.json",
-		config: defaultConfig,
-	}, {
-		in:     "struct.cue",
-		out:    "struct.json",
-		config: defaultConfig,
-	}, {
-		in:     "strings.cue",
-		out:    "strings.json",
-		config: defaultConfig,
-	}, {
-		in:     "nums.cue",
-		out:    "nums.json",
-		config: defaultConfig,
-	}, {
-		in:     "nums.cue",
-		out:    "nums-v3.1.0.json",
-		config: &openapi.Config{Info: info, Version: "3.1.0"},
-	}, {
-		in:     "builtins.cue",
-		out:    "builtins.json",
-		config: defaultConfig,
-	}, {
-		in:     "oneof.cue",
-		out:    "oneof.json",
-		config: defaultConfig,
-	}, {
-		in:     "oneof.cue",
-		out:    "oneof-resolve.json",
-		config: resolveRefs,
-	}, {
-		in:     "openapi.cue",
-		out:    "openapi.json",
-		config: defaultConfig,
-	}, {
-		in:     "openapi.cue",
-		out:    "openapi-norefs.json",
-		config: resolveRefs,
-	}, {
-		in:     "embed.cue",
-		out:    "embed.json",
-		config: defaultConfig,
-	}, {
-		in:     "embed.cue",
-		out:    "embed-norefs.json",
-		config: resolveRefs,
-	}, {
 		in:  "oneof.cue",
 		out: "oneof-funcs.json",
 		config: &openapi.Config{
@@ -154,71 +146,9 @@ func TestParseDefinitions(t *testing.T) {
 				return strings.TrimPrefix(path.String(), "#")
 			},
 		},
-	}, {
-		in:     "issue131.cue",
-		out:    "issue131.json",
-		config: &openapi.Config{Info: info, SelfContained: true},
-	}, {
-		// Issue #915
-		in:     "cycle.cue",
-		out:    "cycle.json",
-		config: &openapi.Config{Info: info},
-	}, {
-		// Issue #915
-		in:     "cycle.cue",
-		config: &openapi.Config{Info: info, ExpandReferences: true},
-		err:    "cycle",
-	}, {
-		in:     "quotedfield.cue",
-		out:    "quotedfield.json",
-		config: defaultConfig,
-	}, {
-		in:     "omitvalue.cue",
-		out:    "omitvalue.json",
-		config: defaultConfig,
-	}, {
-		in:     "issue3718.cue",
-		out:    "issue3718.json",
-		config: defaultConfig,
 	}}
 	for _, tc := range testCases {
-		t.Run(tc.out+tc.variant, func(t *testing.T) {
-			run := func(t *testing.T, inst cue.InstanceOrValue) {
-				b, err := openapi.Gen(inst, tc.config)
-				if err != nil {
-					if tc.err == "" {
-						t.Fatal("unexpected error:", errors.Details(err, nil))
-					}
-					return
-				}
-
-				if tc.err != "" {
-					t.Fatal("unexpected success:", tc.err)
-				} else {
-					_, err := openapi.Generate(inst, tc.config)
-					if err != nil {
-						t.Fatal(err)
-					}
-				}
-
-				var out = &bytes.Buffer{}
-				_ = json.Indent(out, b, "", "   ")
-
-				wantFile := filepath.Join("testdata", tc.out)
-				if cuetest.UpdateGoldenFiles {
-					_ = os.WriteFile(wantFile, out.Bytes(), 0666)
-					return
-				}
-
-				b, err = os.ReadFile(wantFile)
-				if err != nil {
-					t.Fatal(err)
-				}
-
-				if d := cmp.Diff(string(b), out.String()); d != "" {
-					t.Errorf("files differ:\n%v", d)
-				}
-			}
+		t.Run(tc.out, func(t *testing.T) {
 			filename := filepath.FromSlash(tc.in)
 			inst := load.Instances([]string{filename}, &load.Config{
 				Dir: "./testdata",
@@ -228,7 +158,34 @@ func TestParseDefinitions(t *testing.T) {
 			if err := v.Err(); err != nil {
 				t.Fatal(errors.Details(err, nil))
 			}
-			run(t, v)
+
+			b, err := openapi.Gen(v, tc.config)
+			if err != nil {
+				t.Fatal("unexpected error:", errors.Details(err, nil))
+			}
+
+			_, err = openapi.Generate(v, tc.config)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			var out = &bytes.Buffer{}
+			_ = json.Indent(out, b, "", "   ")
+
+			wantFile := filepath.Join("testdata", tc.out)
+			if cuetest.UpdateGoldenFiles {
+				_ = os.WriteFile(wantFile, out.Bytes(), 0666)
+				return
+			}
+
+			b, err = os.ReadFile(wantFile)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if d := cmp.Diff(string(b), out.String()); d != "" {
+				t.Errorf("files differ:\n%v", d)
+			}
 		})
 	}
 }
diff --git a/encoding/openapi/testdata/array.cue b/encoding/openapi/testdata/array.cue
deleted file mode 100644
index 8ef6b25ac..000000000
--- a/encoding/openapi/testdata/array.cue
+++ /dev/null
@@ -1,28 +0,0 @@
-import "list"
-
-#Arrays: {
-	bar?: [...#MyEnum]
-	foo?: [...#MyStruct]
-
-	baz?: list.UniqueItems()
-
-	qux?: list.MinItems(1) & list.MaxItems(3)
-
-	closedConcreteList?: [1, 2, 3]
-	openConcreteList?: [1, 2, 3, ...]
-}
-
-#Arrays: {
-	bar?: [...#MyEnum]
-	foo?: [...#MyStruct]
-}
-
-// MyStruct
-#MyStruct: {
-	a?: int
-	e?: [...#MyEnum]
-	e?: [...#MyEnum]
-}
-
-// MyEnum
-#MyEnum: *"1" | "2" | "3"
diff --git a/encoding/openapi/testdata/array.json b/encoding/openapi/testdata/array.txtar
similarity index 88%
rename from encoding/openapi/testdata/array.json
rename to encoding/openapi/testdata/array.txtar
index 9028c75ea..a3bb3b8b4 100644
--- a/encoding/openapi/testdata/array.json
+++ b/encoding/openapi/testdata/array.txtar
@@ -1,3 +1,34 @@
+-- in.cue --
+import "list"
+
+#Arrays: {
+	bar?: [...#MyEnum]
+	foo?: [...#MyStruct]
+
+	baz?: list.UniqueItems()
+
+	qux?: list.MinItems(1) & list.MaxItems(3)
+
+	closedConcreteList?: [1, 2, 3]
+	openConcreteList?: [1, 2, 3, ...]
+}
+
+#Arrays: {
+	bar?: [...#MyEnum]
+	foo?: [...#MyStruct]
+}
+
+// MyStruct
+#MyStruct: {
+	a?: int
+	e?: [...#MyEnum]
+	e?: [...#MyEnum]
+}
+
+// MyEnum
+#MyEnum: *"1" | "2" | "3"
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/builtins.cue b/encoding/openapi/testdata/builtins.cue
deleted file mode 100644
index cd51239d1..000000000
--- a/encoding/openapi/testdata/builtins.cue
+++ /dev/null
@@ -1,22 +0,0 @@
-import (
-	"time"
-	"list"
-)
-
-let _time = time
-
-#MyStruct: {
-	timestamp1?: time.Time
-	timestamp2?: time.Time()
-	timestamp3?: time.Format(time.RFC3339Nano)
-	timestamp4?: _time.Time
-	date1?:      time.Format(time.RFC3339Date)
-	date2?:      _time.Format(time.RFC3339Date)
-
-	// This is not an OpenAPI type and has no format. In this case
-	// we map to a type so that it can be documented properly (without
-	// repeating it).
-	timeout?: time.Duration
-
-	contains: list.Contains("foo") // not supported, but should be recognized as list
-}
diff --git a/encoding/openapi/testdata/builtins.json b/encoding/openapi/testdata/builtins.txtar
similarity index 69%
rename from encoding/openapi/testdata/builtins.json
rename to encoding/openapi/testdata/builtins.txtar
index 92dc87f93..3132b64ee 100644
--- a/encoding/openapi/testdata/builtins.json
+++ b/encoding/openapi/testdata/builtins.txtar
@@ -1,3 +1,28 @@
+-- in.cue --
+import (
+	"time"
+	"list"
+)
+
+let _time = time
+
+#MyStruct: {
+	timestamp1?: time.Time
+	timestamp2?: time.Time()
+	timestamp3?: time.Format(time.RFC3339Nano)
+	timestamp4?: _time.Time
+	date1?:      time.Format(time.RFC3339Date)
+	date2?:      _time.Format(time.RFC3339Date)
+
+	// This is not an OpenAPI type and has no format. In this case
+	// we map to a type so that it can be documented properly (without
+	// repeating it).
+	timeout?: time.Duration
+
+	contains: list.Contains("foo") // not supported, but should be recognized as list
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/cycle-norefs.txtar b/encoding/openapi/testdata/cycle-norefs.txtar
new file mode 100644
index 000000000..827a07590
--- /dev/null
+++ b/encoding/openapi/testdata/cycle-norefs.txtar
@@ -0,0 +1,6 @@
+#ExpandReferences
+#ExpectError: cycle in reference at #Foo
+-- in.cue --
+		// Issue #915
+#Foo: [string]: #Foo
+
diff --git a/encoding/openapi/testdata/cycle.cue b/encoding/openapi/testdata/cycle.cue
deleted file mode 100644
index eb5cd110b..000000000
--- a/encoding/openapi/testdata/cycle.cue
+++ /dev/null
@@ -1,2 +0,0 @@
-		// Issue #915
-#Foo: [string]: #Foo
diff --git a/encoding/openapi/testdata/cycle.json b/encoding/openapi/testdata/cycle.txtar
similarity index 66%
rename from encoding/openapi/testdata/cycle.json
rename to encoding/openapi/testdata/cycle.txtar
index 49c86dcd2..7cd2d0cd3 100644
--- a/encoding/openapi/testdata/cycle.json
+++ b/encoding/openapi/testdata/cycle.txtar
@@ -1,8 +1,13 @@
+-- in.cue --
+// Issue #915
+#Foo: [string]: #Foo
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "title": "Generated by cue.",
+      "version": "no version"
    },
    "paths": {},
    "components": {
@@ -16,4 +21,4 @@
          }
       }
    }
-}
\ No newline at end of file
+}
diff --git a/encoding/openapi/testdata/embed-norefs.json b/encoding/openapi/testdata/embed-norefs.txtar
similarity index 92%
rename from encoding/openapi/testdata/embed-norefs.json
rename to encoding/openapi/testdata/embed-norefs.txtar
index 4274bcc71..e291b09ce 100644
--- a/encoding/openapi/testdata/embed-norefs.json
+++ b/encoding/openapi/testdata/embed-norefs.txtar
@@ -1,8 +1,24 @@
+#ExpandReferences
+#skip-v3
+-- in.cue --
+#Foo: string
+
+#LoadBalancerSettings: {
+	{} | {
+		consistentHash: #ConsistentHashLB
+		b:              #Foo
+	}
+	#ConsistentHashLB: {} | {
+		httpHeaderName: string
+	}
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "title": "Generated by cue.",
+      "version": "no version"
    },
    "paths": {},
    "components": {
@@ -118,4 +134,4 @@
          }
       }
    }
-}
\ No newline at end of file
+}
diff --git a/encoding/openapi/testdata/embed.cue b/encoding/openapi/testdata/embed.cue
deleted file mode 100644
index c3bc3b4ff..000000000
--- a/encoding/openapi/testdata/embed.cue
+++ /dev/null
@@ -1,11 +0,0 @@
-#Foo: string
-
-#LoadBalancerSettings: {
-	{} | {
-		consistentHash: #ConsistentHashLB
-		b:              #Foo
-	}
-	#ConsistentHashLB: {} | {
-		httpHeaderName: string
-	}
-}
diff --git a/encoding/openapi/testdata/embed.json b/encoding/openapi/testdata/embed.txtar
similarity index 91%
rename from encoding/openapi/testdata/embed.json
rename to encoding/openapi/testdata/embed.txtar
index d88cc2fe7..e4bb5942e 100644
--- a/encoding/openapi/testdata/embed.json
+++ b/encoding/openapi/testdata/embed.txtar
@@ -1,3 +1,19 @@
+#skip-v3
+#skip-v3-noshare
+-- in.cue --
+#Foo: string
+
+#LoadBalancerSettings: {
+	{} | {
+		consistentHash: #ConsistentHashLB
+		b:              #Foo
+	}
+	#ConsistentHashLB: {} | {
+		httpHeaderName: string
+	}
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/enum.cue b/encoding/openapi/testdata/enum.cue
deleted file mode 100644
index 237ff5e57..000000000
--- a/encoding/openapi/testdata/enum.cue
+++ /dev/null
@@ -1,10 +0,0 @@
-#CaptureMode: {
-	"DEFAULT"
-	#enumValue: 0
-} | {
-	"IPTABLES"
-	#enumValue: 1
-} | {
-	"NONE"
-	#enumValue: 2
-}
diff --git a/encoding/openapi/testdata/enum.json b/encoding/openapi/testdata/enum.txtar
similarity index 69%
rename from encoding/openapi/testdata/enum.json
rename to encoding/openapi/testdata/enum.txtar
index 81ca198eb..b5778a089 100644
--- a/encoding/openapi/testdata/enum.json
+++ b/encoding/openapi/testdata/enum.txtar
@@ -1,3 +1,16 @@
+-- in.cue --
+#CaptureMode: {
+	"DEFAULT"
+	#enumValue: 0
+} | {
+	"IPTABLES"
+	#enumValue: 1
+} | {
+	"NONE"
+	#enumValue: 2
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/issue131.cue b/encoding/openapi/testdata/issue131.cue
deleted file mode 100644
index a097d3f15..000000000
--- a/encoding/openapi/testdata/issue131.cue
+++ /dev/null
@@ -1,7 +0,0 @@
-package ext
-
-import "mod.test/blocks"
-
-#Blocks: {
-	block1: blocks.#Block
-}
diff --git a/encoding/openapi/testdata/issue131.json b/encoding/openapi/testdata/issue131.txtar
similarity index 80%
rename from encoding/openapi/testdata/issue131.json
rename to encoding/openapi/testdata/issue131.txtar
index 3025bf567..b58d56126 100644
--- a/encoding/openapi/testdata/issue131.json
+++ b/encoding/openapi/testdata/issue131.txtar
@@ -1,8 +1,19 @@
+#skip-v3-noshare
+-- in.cue --
+package ext
+
+import "mod.test/blocks"
+
+#Blocks: {
+	block1: blocks.#Block
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "title": "Generated by cue.",
+      "version": "no version"
    },
    "paths": {},
    "components": {
@@ -39,4 +50,4 @@
          }
       }
    }
-}
\ No newline at end of file
+}
diff --git a/encoding/openapi/testdata/issue3718.cue b/encoding/openapi/testdata/issue3718.cue
deleted file mode 100644
index 1abaa0e28..000000000
--- a/encoding/openapi/testdata/issue3718.cue
+++ /dev/null
@@ -1,9 +0,0 @@
-import (
-	"encoding/json"
-)
-
-let defaultPolicy = json.Marshal({ deny: "all" })
-
-#Spec: {
-    policy?: string | *defaultPolicy
-}
diff --git a/encoding/openapi/testdata/issue3718.json b/encoding/openapi/testdata/issue3718.txtar
similarity index 69%
rename from encoding/openapi/testdata/issue3718.json
rename to encoding/openapi/testdata/issue3718.txtar
index 9e94e0436..09f0870eb 100644
--- a/encoding/openapi/testdata/issue3718.json
+++ b/encoding/openapi/testdata/issue3718.txtar
@@ -1,3 +1,15 @@
+-- in.cue --
+import (
+	"encoding/json"
+)
+
+let defaultPolicy = json.Marshal({ deny: "all" })
+
+#Spec: {
+    policy?: string | *defaultPolicy
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/nested.cue b/encoding/openapi/testdata/nested.cue
deleted file mode 100644
index 3de5f28ec..000000000
--- a/encoding/openapi/testdata/nested.cue
+++ /dev/null
@@ -1,11 +0,0 @@
-// File comment.
-
-#Struct: {
-	#T: int
-
-	a?: #T
-
-	{b?: #T}
-
-	c?: [...#T]
-}
diff --git a/encoding/openapi/testdata/nested.json b/encoding/openapi/testdata/nested.txtar
similarity index 85%
rename from encoding/openapi/testdata/nested.json
rename to encoding/openapi/testdata/nested.txtar
index e11ce76cc..09087cfa7 100644
--- a/encoding/openapi/testdata/nested.json
+++ b/encoding/openapi/testdata/nested.txtar
@@ -1,3 +1,17 @@
+-- in.cue --
+// File comment.
+
+#Struct: {
+	#T: int
+
+	a?: #T
+
+	{b?: #T}
+
+	c?: [...#T]
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/nums-v3.1.0.json b/encoding/openapi/testdata/nums-v3.1.0.txtar
similarity index 79%
rename from encoding/openapi/testdata/nums-v3.1.0.json
rename to encoding/openapi/testdata/nums-v3.1.0.txtar
index f752a1123..7653295cd 100644
--- a/encoding/openapi/testdata/nums-v3.1.0.json
+++ b/encoding/openapi/testdata/nums-v3.1.0.txtar
@@ -1,8 +1,23 @@
+#Version: 3.1.0
+-- in.cue --
+import "math"
+
+#mul: math.MultipleOf(5)
+
+#neq: !=4
+
+#exMin: >5
+#exMax: <6
+
+#int:     int64
+#intNull: int64 | null
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.1.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "title": "Generated by cue.",
+      "version": "no version"
    },
    "paths": {},
    "components": {
@@ -44,4 +59,4 @@
          }
       }
    }
-}
\ No newline at end of file
+}
diff --git a/encoding/openapi/testdata/nums.cue b/encoding/openapi/testdata/nums.cue
deleted file mode 100644
index 3c25531f4..000000000
--- a/encoding/openapi/testdata/nums.cue
+++ /dev/null
@@ -1,11 +0,0 @@
-import "math"
-
-#mul: math.MultipleOf(5)
-
-#neq: !=4
-
-#exMin: >5
-#exMax: <6
-
-#int:     int64
-#intNull: int64 | null
diff --git a/encoding/openapi/testdata/nums.json b/encoding/openapi/testdata/nums.txtar
similarity index 86%
rename from encoding/openapi/testdata/nums.json
rename to encoding/openapi/testdata/nums.txtar
index 81c025cd9..a5d86656b 100644
--- a/encoding/openapi/testdata/nums.json
+++ b/encoding/openapi/testdata/nums.txtar
@@ -1,3 +1,17 @@
+-- in.cue --
+import "math"
+
+#mul: math.MultipleOf(5)
+
+#neq: !=4
+
+#exMin: >5
+#exMax: <6
+
+#int:     int64
+#intNull: int64 | null
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/omitvalue.cue b/encoding/openapi/testdata/omitvalue.cue
deleted file mode 100644
index 1fbcc385b..000000000
--- a/encoding/openapi/testdata/omitvalue.cue
+++ /dev/null
@@ -1,8 +0,0 @@
-#D: {
-	a: int
-	#b: int
-	a_value: int
-	// Only definitions ending in _value are omitted.
-	#b_value: int
-	"a b_value": int
-}
diff --git a/encoding/openapi/testdata/omitvalue.json b/encoding/openapi/testdata/omitvalue.txtar
similarity index 79%
rename from encoding/openapi/testdata/omitvalue.json
rename to encoding/openapi/testdata/omitvalue.txtar
index c60a37e78..e415f576a 100644
--- a/encoding/openapi/testdata/omitvalue.json
+++ b/encoding/openapi/testdata/omitvalue.txtar
@@ -1,3 +1,14 @@
+-- in.cue --
+#D: {
+	a: int
+	#b: int
+	a_value: int
+	// Only definitions ending in _value are omitted.
+	#b_value: int
+	"a b_value": int
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/oneof-resolve.json b/encoding/openapi/testdata/oneof-resolve.txtar
similarity index 94%
rename from encoding/openapi/testdata/oneof-resolve.json
rename to encoding/openapi/testdata/oneof-resolve.txtar
index 643029de7..7de9e1612 100644
--- a/encoding/openapi/testdata/oneof-resolve.json
+++ b/encoding/openapi/testdata/oneof-resolve.txtar
@@ -1,8 +1,88 @@
+#ExpandReferences
+#skip-v3
+#skip-v3-noshare
+-- in.cue --
+// OpenAPI title.
+
+$version: "v1alpha1"
+
+#T: {
+	shared: int
+}
+#T: {} | {
+	exact: string
+} | {
+	regex: string
+}
+#T: {} | {
+	count: int
+} | {
+	amount: int
+}
+#T: {
+	shared2: int
+}
+
+// This should be dedupped.
+#T: {} | {
+	count: int
+} | {
+	amount: int
+}
+
+#MyInt: int
+
+#Foo: {
+	include: #T
+	exclude: [...#T]
+	count: #MyInt
+}
+
+#Incompatible: {
+	shared: int
+} | {
+	shared: int
+	extra1: int
+} | {
+	shared: int
+	extra2: int
+}
+
+#WithMap: {
+	shared: [string]: int
+} | {
+	shared: [string]: int
+	extra: int
+} | {
+	shared: string // incompatible
+	extra:  int
+}
+
+#Embed: {
+	a?: int
+
+	close({}) |
+	close({b: #T}) |
+	close({c: int})
+
+	#T: {b?: int}
+
+	close({}) |
+	close({d: #T}) |
+	close({e: int})
+
+	// TODO: maybe support builtin to write this as
+	// oneof({},
+	// {b: int},
+	// {c: int})
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "title": "OpenAPI title.",
+      "version": "v1alpha1"
    },
    "paths": {},
    "components": {
@@ -516,4 +596,4 @@
          }
       }
    }
-}
\ No newline at end of file
+}
diff --git a/encoding/openapi/testdata/oneof.json b/encoding/openapi/testdata/oneof.txtar
similarity index 94%
rename from encoding/openapi/testdata/oneof.json
rename to encoding/openapi/testdata/oneof.txtar
index 2c8429749..93ff4b055 100644
--- a/encoding/openapi/testdata/oneof.json
+++ b/encoding/openapi/testdata/oneof.txtar
@@ -1,3 +1,82 @@
+#skip-v3
+#skip-v3-noshare
+-- in.cue --
+// OpenAPI title.
+
+$version: "v1alpha1"
+
+#T: {
+	shared: int
+}
+#T: {} | {
+	exact: string
+} | {
+	regex: string
+}
+#T: {} | {
+	count: int
+} | {
+	amount: int
+}
+#T: {
+	shared2: int
+}
+
+// This should be dedupped.
+#T: {} | {
+	count: int
+} | {
+	amount: int
+}
+
+#MyInt: int
+
+#Foo: {
+	include: #T
+	exclude: [...#T]
+	count: #MyInt
+}
+
+#Incompatible: {
+	shared: int
+} | {
+	shared: int
+	extra1: int
+} | {
+	shared: int
+	extra2: int
+}
+
+#WithMap: {
+	shared: [string]: int
+} | {
+	shared: [string]: int
+	extra: int
+} | {
+	shared: string // incompatible
+	extra:  int
+}
+
+#Embed: {
+	a?: int
+
+	close({}) |
+	close({b: #T}) |
+	close({c: int})
+
+	#T: {b?: int}
+
+	close({}) |
+	close({d: #T}) |
+	close({e: int})
+
+	// TODO: maybe support builtin to write this as
+	// oneof({},
+	// {b: int},
+	// {c: int})
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/openapi-norefs.json b/encoding/openapi/testdata/openapi-norefs.txtar
similarity index 86%
rename from encoding/openapi/testdata/openapi-norefs.json
rename to encoding/openapi/testdata/openapi-norefs.txtar
index 69a9f98a8..cc0c02a67 100644
--- a/encoding/openapi/testdata/openapi-norefs.json
+++ b/encoding/openapi/testdata/openapi-norefs.txtar
@@ -1,8 +1,63 @@
+#ExpandReferences
+-- in.cue --
+// An OpenAPI testing package.
+package openapi
+
+$version: "v1beta2"
+
+info: {
+	contact: url:  "https://cuelang.org"
+	contact: name: "John Doe"
+}
+
+// MyMessage is my message.
+#MyMessage: {
+	port?: #Port & {} @protobuf(1)
+
+	foo: #Int32 & >10 & <1000 & int32 @protobuf(2)
+
+	bar: [...string] @protobuf(3)
+}
+
+#MyMessage: {
+	// Field a.
+	a: 1
+} | {
+	b: string //2: crash
+}
+
+#YourMessage: ({a: number} | {b: string} | {b: number}) & {a?: string}
+
+#YourMessage2: ({a: number} | {b: number}) &
+	({c: number} | {d: number}) &
+	({e: number} | {f: number})
+
+#Msg2: {b: number} | {a: string}
+
+#Int32: int32
+
+#Enum: "foo" | "bar" | "baz"
+
+#List: [...number] | *[1, 2, 3]
+
+#DefaultStruct: #Port | *{port: 1}
+
+#Port: {
+	port: int
+
+	obj: [...int]
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "contact": {
+         "url": "https://cuelang.org",
+         "name": "John Doe"
+      },
+      "title": "An OpenAPI testing package.",
+      "version": "v1beta2"
    },
    "paths": {},
    "components": {
@@ -257,4 +312,4 @@
          }
       }
    }
-}
\ No newline at end of file
+}
diff --git a/encoding/openapi/testdata/openapi.cue b/encoding/openapi/testdata/openapi.cue
deleted file mode 100644
index 83d81c19d..000000000
--- a/encoding/openapi/testdata/openapi.cue
+++ /dev/null
@@ -1,47 +0,0 @@
-// An OpenAPI testing package.
-package openapi
-
-$version: "v1beta2"
-
-info: {
-	contact: url:  "https://cuelang.org"
-	contact: name: "John Doe"
-}
-
-// MyMessage is my message.
-#MyMessage: {
-	port?: #Port & {} @protobuf(1)
-
-	foo: #Int32 & >10 & <1000 & int32 @protobuf(2)
-
-	bar: [...string] @protobuf(3)
-}
-
-#MyMessage: {
-	// Field a.
-	a: 1
-} | {
-	b: string //2: crash
-}
-
-#YourMessage: ({a: number} | {b: string} | {b: number}) & {a?: string}
-
-#YourMessage2: ({a: number} | {b: number}) &
-	({c: number} | {d: number}) &
-	({e: number} | {f: number})
-
-#Msg2: {b: number} | {a: string}
-
-#Int32: int32
-
-#Enum: "foo" | "bar" | "baz"
-
-#List: [...number] | *[1, 2, 3]
-
-#DefaultStruct: #Port | *{port: 1}
-
-#Port: {
-	port: int
-
-	obj: [...int]
-}
diff --git a/encoding/openapi/testdata/openapi.json b/encoding/openapi/testdata/openapi.txtar
similarity index 90%
rename from encoding/openapi/testdata/openapi.json
rename to encoding/openapi/testdata/openapi.txtar
index 90fd2cbcc..aaca2ffad 100644
--- a/encoding/openapi/testdata/openapi.json
+++ b/encoding/openapi/testdata/openapi.txtar
@@ -1,3 +1,55 @@
+#skip-v3
+#skip-v3-noshare
+-- in.cue --
+// An OpenAPI testing package.
+package openapi
+
+$version: "v1beta2"
+
+info: {
+	contact: url:  "https://cuelang.org"
+	contact: name: "John Doe"
+}
+
+// MyMessage is my message.
+#MyMessage: {
+	port?: #Port & {} @protobuf(1)
+
+	foo: #Int32 & >10 & <1000 & int32 @protobuf(2)
+
+	bar: [...string] @protobuf(3)
+}
+
+#MyMessage: {
+	// Field a.
+	a: 1
+} | {
+	b: string //2: crash
+}
+
+#YourMessage: ({a: number} | {b: string} | {b: number}) & {a?: string}
+
+#YourMessage2: ({a: number} | {b: number}) &
+	({c: number} | {d: number}) &
+	({e: number} | {f: number})
+
+#Msg2: {b: number} | {a: string}
+
+#Int32: int32
+
+#Enum: "foo" | "bar" | "baz"
+
+#List: [...number] | *[1, 2, 3]
+
+#DefaultStruct: #Port | *{port: 1}
+
+#Port: {
+	port: int
+
+	obj: [...int]
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/protobuf.cue b/encoding/openapi/testdata/protobuf.cue
deleted file mode 100644
index aeb3c25e9..000000000
--- a/encoding/openapi/testdata/protobuf.cue
+++ /dev/null
@@ -1,12 +0,0 @@
-// Note: This example originally derived from a CUE file converted from protobuf.
-
-#HTTPRoute: {
-	route: [...#HTTPRouteDestination]
-}
-#HTTPRouteDestination: {
-	headers:     #Headers
-}
-#Headers: {
-	request:  #HeaderOperations
-	#HeaderOperations:  {}
-}
diff --git a/encoding/openapi/testdata/protobuf.json b/encoding/openapi/testdata/protobuf.txtar
similarity index 81%
rename from encoding/openapi/testdata/protobuf.json
rename to encoding/openapi/testdata/protobuf.txtar
index b23947592..cab1167a7 100644
--- a/encoding/openapi/testdata/protobuf.json
+++ b/encoding/openapi/testdata/protobuf.txtar
@@ -1,8 +1,25 @@
+#ExpandReferences
+#skip-v3
+-- in.cue --
+// Note: This example originally derived from a CUE file converted from protobuf.
+
+#HTTPRoute: {
+	route: [...#HTTPRouteDestination]
+}
+#HTTPRouteDestination: {
+	headers:     #Headers
+}
+#Headers: {
+	request:  #HeaderOperations
+	#HeaderOperations:  {}
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "title": "Note: This example originally derived from a CUE file converted from protobuf.",
+      "version": "no version"
    },
    "paths": {},
    "components": {
diff --git a/encoding/openapi/testdata/quotedfield.cue b/encoding/openapi/testdata/quotedfield.cue
deleted file mode 100644
index f55bd9756..000000000
--- a/encoding/openapi/testdata/quotedfield.cue
+++ /dev/null
@@ -1,3 +0,0 @@
-#Def: {
-    "@type": string
-}
diff --git a/encoding/openapi/testdata/quotedfield.json b/encoding/openapi/testdata/quotedfield.txtar
similarity index 83%
rename from encoding/openapi/testdata/quotedfield.json
rename to encoding/openapi/testdata/quotedfield.txtar
index c9994ffe6..85afbbaa6 100644
--- a/encoding/openapi/testdata/quotedfield.json
+++ b/encoding/openapi/testdata/quotedfield.txtar
@@ -1,3 +1,9 @@
+-- in.cue --
+#Def: {
+    "@type": string
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/script/basics.txtar b/encoding/openapi/testdata/script/basics.txtar
index b5a5943c4..e856479b6 100644
--- a/encoding/openapi/testdata/script/basics.txtar
+++ b/encoding/openapi/testdata/script/basics.txtar
@@ -45,3 +45,39 @@ info: {
 	address?: #PhoneNumber
 	...
 }
+-- out/TestGenerateOpenAPI/out.json --
+{
+   "openapi": "3.0.0",
+   "info": {
+      "title": "Users schema",
+      "version": "v1beta1",
+      "contact": {
+         "name": "The CUE Authors",
+         "url": "https://cuelang.org"
+      }
+   },
+   "paths": {},
+   "components": {
+      "schemas": {
+         "PhoneNumber": {
+            "description": "The number to dial.",
+            "type": "string"
+         },
+         "User": {
+            "description": "A User uses something.",
+            "type": "object",
+            "properties": {
+               "id": {
+                  "type": "integer"
+               },
+               "name": {
+                  "type": "string"
+               },
+               "address": {
+                  "$ref": "#/components/schemas/PhoneNumber"
+               }
+            }
+         }
+      }
+   }
+}
diff --git a/encoding/openapi/testdata/simple-filter.json b/encoding/openapi/testdata/simple-filter.txtar
similarity index 77%
rename from encoding/openapi/testdata/simple-filter.json
rename to encoding/openapi/testdata/simple-filter.txtar
index fdf870822..b543f4d58 100644
--- a/encoding/openapi/testdata/simple-filter.json
+++ b/encoding/openapi/testdata/simple-filter.txtar
@@ -1,8 +1,21 @@
+#FieldFilter: min.*|max.*
+-- in.cue --
+#MyStruct: {
+	mediumNum: int32
+	smallNum:  int8
+
+	float:  float32
+	double: float64
+
+	deprecatedField: string @protobuf(5,deprecated)
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "title": "Generated by cue.",
+      "version": "no version"
    },
    "paths": {},
    "components": {
diff --git a/encoding/openapi/testdata/simple.cue b/encoding/openapi/testdata/simple.cue
deleted file mode 100644
index 92b8475ce..000000000
--- a/encoding/openapi/testdata/simple.cue
+++ /dev/null
@@ -1,9 +0,0 @@
-#MyStruct: {
-	mediumNum: int32
-	smallNum:  int8
-
-	float:  float32
-	double: float64
-
-	deprecatedField: string @protobuf(5,deprecated)
-}
diff --git a/encoding/openapi/testdata/simple.json b/encoding/openapi/testdata/simple.txtar
similarity index 79%
rename from encoding/openapi/testdata/simple.json
rename to encoding/openapi/testdata/simple.txtar
index 4429e7037..cad8b4f37 100644
--- a/encoding/openapi/testdata/simple.json
+++ b/encoding/openapi/testdata/simple.txtar
@@ -1,8 +1,21 @@
+#ExpandReferences
+-- in.cue --
+#MyStruct: {
+	mediumNum: int32
+	smallNum:  int8
+
+	float:  float32
+	double: float64
+
+	deprecatedField: string @protobuf(5,deprecated)
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "title": "Generated by cue.",
+      "version": "no version"
    },
    "paths": {},
    "components": {
diff --git a/encoding/openapi/testdata/strings.cue b/encoding/openapi/testdata/strings.cue
deleted file mode 100644
index 84e47c727..000000000
--- a/encoding/openapi/testdata/strings.cue
+++ /dev/null
@@ -1,9 +0,0 @@
-import "strings"
-
-#MyType: {
-	myString: strings.MinRunes(1) & strings.MaxRunes(5)
-
-	myPattern: =~"foo.*bar"
-
-	myAntiPattern: !~"foo.*bar"
-}
diff --git a/encoding/openapi/testdata/strings.json b/encoding/openapi/testdata/strings.txtar
similarity index 81%
rename from encoding/openapi/testdata/strings.json
rename to encoding/openapi/testdata/strings.txtar
index 2a5411fc0..4b15ce634 100644
--- a/encoding/openapi/testdata/strings.json
+++ b/encoding/openapi/testdata/strings.txtar
@@ -1,3 +1,15 @@
+-- in.cue --
+import "strings"
+
+#MyType: {
+	myString: strings.MinRunes(1) & strings.MaxRunes(5)
+
+	myPattern: =~"foo.*bar"
+
+	myAntiPattern: !~"foo.*bar"
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/struct.cue b/encoding/openapi/testdata/struct.cue
deleted file mode 100644
index 82406f817..000000000
--- a/encoding/openapi/testdata/struct.cue
+++ /dev/null
@@ -1,8 +0,0 @@
-import "struct"
-
-#MyMap: struct.MinFields(4)
-#MyMap: struct.MaxFields(9)
-
-#MyType: {
-	map: #MyMap
-}
diff --git a/encoding/openapi/testdata/struct.json b/encoding/openapi/testdata/struct.txtar
similarity index 76%
rename from encoding/openapi/testdata/struct.json
rename to encoding/openapi/testdata/struct.txtar
index 3af6ee365..991718e4c 100644
--- a/encoding/openapi/testdata/struct.json
+++ b/encoding/openapi/testdata/struct.txtar
@@ -1,3 +1,15 @@
+#skip-v3-noshare
+-- in.cue --
+import "struct"
+
+#MyMap: struct.MinFields(4)
+#MyMap: struct.MaxFields(9)
+
+#MyType: {
+	map: #MyMap
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
diff --git a/encoding/openapi/testdata/structural.cue b/encoding/openapi/testdata/structural.cue
deleted file mode 100644
index 1f0b892cd..000000000
--- a/encoding/openapi/testdata/structural.cue
+++ /dev/null
@@ -1,44 +0,0 @@
-import "time"
-
-#Attributes: {
-	//  A map of attribute name to its value.
-	attributes: {
-		[string]: #AttrValue
-	}
-}
-
-//  The attribute value.
-#AttrValue: {}
-
-#AttrValue: {
-	//  Used for values of type STRING, DNS_NAME, EMAIL_ADDRESS, and URI
-	stringValue: string @protobuf(2,name=string_value)
-} | {
-	//  Used for values of type INT64
-	int64Value: int64 @protobuf(3,name=int64_value)
-} | {
-	//  Used for values of type DOUBLE
-	doubleValue: float64 @protobuf(4,type=double,name=double_value)
-} | {
-	//  Used for values of type BOOL
-	boolValue: bool @protobuf(5,name=bool_value)
-} | {
-	//  Used for values of type BYTES
-	bytesValue: bytes @protobuf(6,name=bytes_value)
-} | {
-	//  Used for values of type TIMESTAMP
-	timestampValue: time.Time @protobuf(7,type=google.protobuf.Timestamp,name=timestamp_value)
-} | {
-	//  Used for values of type DURATION
-	durationValue: time.Duration @protobuf(8,type=google.protobuf.Duration,name=duration_value)
-} | {
-	//  Used for values of type STRING_MAP
-	stringMapValue: #Attributes_StringMap @protobuf(9,type=StringMap,name=string_map_value)
-}
-
-#Attributes_StringMap: {
-	//  Holds a set of name/value pairs.
-	entries: {
-		[string]: string
-	} @protobuf(1,type=map<string,string>)
-}
diff --git a/encoding/openapi/testdata/structural.json b/encoding/openapi/testdata/structural.txtar
similarity index 85%
rename from encoding/openapi/testdata/structural.json
rename to encoding/openapi/testdata/structural.txtar
index a483851f7..eac3c6f0c 100644
--- a/encoding/openapi/testdata/structural.json
+++ b/encoding/openapi/testdata/structural.txtar
@@ -1,8 +1,57 @@
+#ExpandReferences
+#skip-v3
+-- in.cue --
+import "time"
+
+#Attributes: {
+	//  A map of attribute name to its value.
+	attributes: {
+		[string]: #AttrValue
+	}
+}
+
+//  The attribute value.
+#AttrValue: {}
+
+#AttrValue: {
+	//  Used for values of type STRING, DNS_NAME, EMAIL_ADDRESS, and URI
+	stringValue: string @protobuf(2,name=string_value)
+} | {
+	//  Used for values of type INT64
+	int64Value: int64 @protobuf(3,name=int64_value)
+} | {
+	//  Used for values of type DOUBLE
+	doubleValue: float64 @protobuf(4,type=double,name=double_value)
+} | {
+	//  Used for values of type BOOL
+	boolValue: bool @protobuf(5,name=bool_value)
+} | {
+	//  Used for values of type BYTES
+	bytesValue: bytes @protobuf(6,name=bytes_value)
+} | {
+	//  Used for values of type TIMESTAMP
+	timestampValue: time.Time @protobuf(7,type=google.protobuf.Timestamp,name=timestamp_value)
+} | {
+	//  Used for values of type DURATION
+	durationValue: time.Duration @protobuf(8,type=google.protobuf.Duration,name=duration_value)
+} | {
+	//  Used for values of type STRING_MAP
+	stringMapValue: #Attributes_StringMap @protobuf(9,type=StringMap,name=string_map_value)
+}
+
+#Attributes_StringMap: {
+	//  Holds a set of name/value pairs.
+	entries: {
+		[string]: string
+	} @protobuf(1,type=map<string,string>)
+}
+
+-- out/TestGenerateOpenAPI/out.json --
 {
    "openapi": "3.0.0",
    "info": {
-      "title": "test",
-      "version": "v1"
+      "title": "Generated by cue.",
+      "version": "no version"
    },
    "paths": {},
    "components": {
@@ -227,4 +276,4 @@
          }
       }
    }
-}
\ No newline at end of file
+}