feat(schema): testing utilities (#20705)

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

schema/testing/module_schema.go

@@ -0,0 +1,51 @@
+package schematesting
+
+import (
+	"fmt"
+
+	"pgregory.net/rapid"
+
+	"cosmossdk.io/schema"
+)
+
+// ModuleSchemaGen generates random ModuleSchema's based on the validity criteria of module schemas.
+var ModuleSchemaGen = rapid.Custom(func(t *rapid.T) schema.ModuleSchema {
+	objectTypes := objectTypesGen.Draw(t, "objectTypes")
+	modSchema, err := schema.NewModuleSchema(objectTypes)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return modSchema
+})
+
+var objectTypesGen = rapid.Custom(func(t *rapid.T) []schema.ObjectType {
+	var objectTypes []schema.ObjectType
+	numObjectTypes := rapid.IntRange(1, 10).Draw(t, "numObjectTypes")
+	for i := 0; i < numObjectTypes; i++ {
+		objectType := ObjectTypeGen.Draw(t, fmt.Sprintf("objectType[%d]", i))
+		objectTypes = append(objectTypes, objectType)
+	}
+	return objectTypes
+}).Filter(func(objectTypes []schema.ObjectType) bool {
+	typeNames := map[string]bool{}
+	for _, objectType := range objectTypes {
+		if hasDuplicateNames(typeNames, objectType.KeyFields) || hasDuplicateNames(typeNames, objectType.ValueFields) {
+			return false
+		}
+		if typeNames[objectType.Name] {
+			return false
+		}
+		typeNames[objectType.Name] = true
+	}
+	return true
+})
+
+// MustNewModuleSchema calls NewModuleSchema and panics if there's an error. This should generally be used
+// only in tests or initialization code.
+func MustNewModuleSchema(objectTypes []schema.ObjectType) schema.ModuleSchema {
+	schema, err := schema.NewModuleSchema(objectTypes)
+	if err != nil {
+		panic(err)
+	}
+	return schema
+}