Implement randomized schema test (#227)

Resolves #183

This adds a new TestRandomizedSchema that generates a schema using
random number generator, then compiles and runs the tests for the schema.

The new test revealed a number of bugs. I fixed a few of the smaller ones.
There are more bugs, but I don't want to overload this PR. For now
TestRandomizedSchema does not fail the build when it finds a buggy schema,
but merely logs it. After this PR is merged I will fix every failing
schema one by one.

Author: tigrannajaryan

examples/ints/go.mod

@@ -1,6 +1,6 @@
 module github.com/splunk/stef/examples/ints
 
-go 1.23.2
+go 1.24.0
 
 require (
 	github.com/splunk/stef/go/pkg v0.0.8

examples/ints/internal/ints/record.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"sort"
+	"strings"
 )
 
 // Schema is a STEF schema description, serializable in JSON format.
@@ -606,6 +607,130 @@ func (d *Schema) markReachableFromFieldType(
 	}
 }
 
+// PrettyPrint outputs the schema in SDL format.
+func (d *Schema) PrettyPrint() string {
+	var out []string
+
+	// Print package declaration
+	out = append(out, fmt.Sprintf("package %s", strings.Join(d.PackageName, ".")))
+
+	// Print enums
+	for _, enum := range sortedList(d.Enums) {
+		out = append(out, prettyPrintEnum(enum))
+	}
+
+	// Print multimaps
+	for _, mm := range sortedList(d.Multimaps) {
+		out = append(out, prettyPrintMultimap(mm))
+	}
+
+	// Print structs and oneofs
+	for _, s := range sortedList(d.Structs) {
+		out = append(out, prettyPrintStruct(s))
+	}
+
+	return strings.Join(out, "\n\n")
+}
+
+func sortedList[T any](m map[string]*T) []*T {
+	var names []string
+	for k := range m {
+		names = append(names, k)
+	}
+	sort.Strings(names)
+	var out []*T
+	for _, n := range names {
+		out = append(out, m[n])
+	}
+	return out
+}
+
+func prettyPrintEnum(e *Enum) string {
+	out := fmt.Sprintf("enum %s {", e.Name)
+	for _, f := range e.Fields {
+		out += fmt.Sprintf("\n  %s = %d", f.Name, f.Value)
+	}
+	out += "\n}"
+	return out
+}
+
+func prettyPrintMultimap(m *Multimap) string {
+	out := fmt.Sprintf("multimap %s {\n", m.Name)
+	out += "  key " + prettyPrintFieldType(&m.Key.Type)
+	if dict := m.Key.Type.DictName; dict != "" {
+		out += fmt.Sprintf(" dict(%s)", dict)
+	}
+	out += "\n"
+	out += "  value " + prettyPrintFieldType(&m.Value.Type)
+	if dict := m.Value.Type.DictName; dict != "" {
+		out += fmt.Sprintf(" dict(%s)", dict)
+	}
+	out += "\n}"
+	return out
+}
+
+func prettyPrintStruct(s *Struct) string {
+	var out string
+	if s.OneOf {
+		out = fmt.Sprintf("oneof %s {", s.Name)
+	} else {
+		out = fmt.Sprintf("struct %s", s.Name)
+		if s.DictName != "" {
+			out += fmt.Sprintf(" dict(%s)", s.DictName)
+		}
+		if s.IsRoot {
+			out += " root"
+		}
+		out += " {"
+	}
+	for _, f := range s.Fields {
+		out += "\n  " + prettyPrintStructField(f)
+	}
+	out += "\n}"
+	return out
+}
+
+func prettyPrintStructField(f *StructField) string {
+	ft := prettyPrintFieldType(&f.FieldType)
+	out := fmt.Sprintf("%s %s", f.Name, ft)
+	if f.DictName != "" {
+		out += fmt.Sprintf(" dict(%s)", f.DictName)
+	}
+	if f.Optional {
+		out += " optional"
+	}
+	return out
+}
+
+func prettyPrintFieldType(ft *FieldType) string {
+	switch {
+	case ft.Primitive != nil:
+		switch ft.Primitive.Type {
+		case PrimitiveTypeInt64:
+			return "int64"
+		case PrimitiveTypeUint64:
+			return "uint64"
+		case PrimitiveTypeFloat64:
+			return "float64"
+		case PrimitiveTypeBool:
+			return "bool"
+		case PrimitiveTypeString:
+			return "string"
+		case PrimitiveTypeBytes:
+			return "bytes"
+		}
+	case ft.Array != nil:
+		return "[]" + prettyPrintFieldType(&ft.Array.ElemType)
+	case ft.Struct != "":
+		return ft.Struct
+	case ft.MultiMap != "":
+		return ft.MultiMap
+	case ft.Enum != "":
+		return ft.Enum
+	}
+	return "unknown"
+}
+
 type Struct struct {
 	Name     string                  `json:"name,omitempty"`
 	OneOf    bool                    `json:"oneof,omitempty"`

examples/jsonl/internal/jsonstef/jsonobject.go

@@ -0,0 +1,129 @@
+package schema
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestPrettyPrint_SimpleStruct(t *testing.T) {
+	schema := &Schema{
+		PackageName: []string{"com", "example", "test"},
+		Structs: map[string]*Struct{
+			"Person": {
+				Name: "Person",
+				Fields: []*StructField{
+					{Name: "Name", FieldType: FieldType{Primitive: &PrimitiveType{Type: PrimitiveTypeString}}},
+					{Name: "Age", FieldType: FieldType{Primitive: &PrimitiveType{Type: PrimitiveTypeUint64}}},
+				},
+			},
+		},
+	}
+
+	expected := `package com.example.test
+
+struct Person {
+  Name string
+  Age uint64
+}`
+	actual := strings.TrimSpace(schema.PrettyPrint())
+	require.Equal(t, expected, actual)
+}
+
+func TestPrettyPrint_EnumAndMultimap(t *testing.T) {
+	schema := &Schema{
+		PackageName: []string{"com", "example", "test"},
+		Enums: map[string]*Enum{
+			"MetricType": {
+				Name: "MetricType",
+				Fields: []EnumField{
+					{Name: "Gauge", Value: 0},
+					{Name: "Counter", Value: 1},
+				},
+			},
+		},
+		Multimaps: map[string]*Multimap{
+			"Labels": {
+				Name: "Labels",
+				Key: MultimapField{
+					Type: FieldType{
+						Primitive: &PrimitiveType{Type: PrimitiveTypeString}, DictName: "LabelKeys",
+					},
+				},
+				Value: MultimapField{
+					Type: FieldType{
+						Primitive: &PrimitiveType{Type: PrimitiveTypeString}, DictName: "LabelValues",
+					},
+				},
+			},
+		},
+	}
+
+	expected := `package com.example.test
+
+enum MetricType {
+  Gauge = 0
+  Counter = 1
+}
+
+multimap Labels {
+  key string dict(LabelKeys)
+  value string dict(LabelValues)
+}`
+	actual := strings.TrimSpace(schema.PrettyPrint())
+	require.Equal(t, expected, actual)
+}
+
+func TestPrettyPrint_OneofAndArray(t *testing.T) {
+	schema := &Schema{
+		PackageName: []string{"example"},
+		Structs: map[string]*Struct{
+			"JsonValue": {
+				Name:  "JsonValue",
+				OneOf: true,
+				Fields: []*StructField{
+					{Name: "String", FieldType: FieldType{Primitive: &PrimitiveType{Type: PrimitiveTypeString}}},
+					{Name: "Number", FieldType: FieldType{Primitive: &PrimitiveType{Type: PrimitiveTypeFloat64}}},
+					{Name: "Array", FieldType: FieldType{Array: &ArrayType{ElemType: FieldType{Struct: "JsonValue"}}}},
+				},
+			},
+		},
+	}
+	expected := `package example
+
+oneof JsonValue {
+  String string
+  Number float64
+  Array []JsonValue
+}`
+	actual := strings.TrimSpace(schema.PrettyPrint())
+	require.Equal(t, expected, actual)
+}
+
+func TestPrettyPrint_OptionalAndDict(t *testing.T) {
+	schema := &Schema{
+		PackageName: []string{"example"},
+		Structs: map[string]*Struct{
+			"User": {
+				Name: "User",
+				Fields: []*StructField{
+					{Name: "Name", FieldType: FieldType{Primitive: &PrimitiveType{Type: PrimitiveTypeString}}},
+					{
+						Name:      "Email",
+						FieldType: FieldType{Primitive: &PrimitiveType{Type: PrimitiveTypeString}, DictName: "Emails"},
+						Optional:  true,
+					},
+				},
+			},
+		},
+	}
+	expected := `package example
+
+struct User {
+  Name string
+  Email string dict(Emails) optional
+}`
+	actual := strings.TrimSpace(schema.PrettyPrint())
+	require.Equal(t, expected, actual)
+}

examples/profile/internal/profile/labels.go

@@ -135,21 +135,16 @@ public void append(StringValue k, AnyValue v) {
         elems[elemsLen-1] = elem;
     }
 
+    
     // setKey sets the key of the element at index i.
     public void setKey(int i, StringValue k) {
         if (!Types.StringEqual(elems[i].key, k)) {
             elems[i].key = k;
             modifiedElems.markKeyModified(i);
         }
     }
-
-    // setValue sets the value of the element at index i.
-    public void setValue(int i, AnyValue v) {
-        if (!elems[i].value.equals(v)) {
-            elems[i].value = v;
-            modifiedElems.markValModified(i);
-        }
-    }
+    
+    
 
     // byteSize returns approximate memory usage in bytes. Used to calculate
     // memory used by dictionaries.