Parse of empty string was returning invalid sting

.gitignore

@@ -1,3 +1,11 @@
+# AI
+.agents/
+.claude/
+.gemini/
+plans/
+GEMINI.md
+CLAUDE.md
+
 # VStudio stuff
 /.vs
 /.vscode

CHANGELOG.md

@@ -5,6 +5,16 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.2.8] - 2026-09-13
+
+### Changed
+- Incremented version to 0.2.8.
+- **Breaking Change**: Conformed empty and whitespace-only document parsing to RFC 4627, RFC 7159, RFC 8259, and JSON5 specifications. Parsing empty strings, whitespace-only content, or empty files now returns `nullptr` (or throws `TJParseException` when `throw_exception = true`) instead of fabricating an empty `TJValueString`.
+- `TJ::is_valid("")` now correctly returns `false`.
+
+### Fixed
+- Fixed inconsistent behaviour where JSON5 returned `nullptr` on empty input while RFC 7159/8259 returned a `TJValueString`.
+
 ## [0.2.7] - 2026-06-27
 
 ### Added
@@ -22,7 +32,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added warning callback trigger when attempting to retrieve non-existent keys in `TJValueObject` using `try_get_string`, `get_*(..)`, or `get<>(..)` methods.
 
 ### Changed
-- Incremented version to 0.3.0.
+- Incremented version to 0.2.8.
 
 ## [0.2.4] - 2026-05-20
 

README.md

@@ -2,7 +2,7 @@
 
 [![CI](https://github.com/FFMG/TinyJSON/actions/workflows/c-cpp.yml/badge.svg)](https://github.com/FFMG/TinyJSON/actions/workflows/c-cpp.yml)
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)
-[![Version](https://img.shields.io/badge/version-0.2.7-blue.svg)](src/TinyJSON.h)
+[![Version](https://img.shields.io/badge/version-0.2.8-blue.svg)](src/TinyJSON.h)
 
 A lightweight and lightning-fast C++ JSON & JSON5 parser designed for high performance and minimal footprint.
 
@@ -131,8 +131,8 @@ The version is set in the `TinyJSON.h` file.
 ```cpp
 static const short TJ_VERSION_MAJOR = 0;
 static const short TJ_VERSION_MINOR = 2;
-static const short TJ_VERSION_PATCH = 7;
-static const char TJ_VERSION_STRING[] = "0.2.7";
+static const short TJ_VERSION_PATCH = 8;
+static const char TJ_VERSION_STRING[] = "0.2.8";
 ```
 
 ### Simple Value Access

src/TinyJSON.cpp

@@ -4222,15 +4222,16 @@ namespace TinyJSON
       return nullptr;
     }
 
-    if (value_found == nullptr && parse_options.specification == parse_options::json5_1_0_0)
+    if (value_found == nullptr)
     {
-       // JSON5 requires a value
-       return nullptr;
+      parse_result.assign_exception_message(TJCHARPREFIX("The JSON text is empty or contains no value."));
+      parse_result.throw_if_exception();
+      return nullptr;
     }
 
     if (parse_options.specification == parse_options::rfc4627 && !parse_result.has_exception_message())
     {
-      if (value_found == nullptr || (!value_found->is_array() && !value_found->is_object()))
+      if (!value_found->is_array() && !value_found->is_object())
       {
         // error: RFC 4627: A JSON text must be either an object or an array.
         parse_result.assign_exception_message("RFC 4627: A JSON text must be either an object or an array.");
@@ -4243,13 +4244,8 @@ namespace TinyJSON
     }
 
     // return if we found anything.
-    // if we found nothing ... then it is not an error, just an empty string
     parse_result.throw_if_exception();
-    if (value_found == nullptr && parse_result.options().specification == parse_options::json5_1_0_0)
-    {
-       return nullptr;
-    }
-    return value_found != nullptr ? value_found : new TJValueString(TJCHARPREFIX(""));
+    return value_found;
   }
 
   /// <summary>

src/TinyJSON.h

@@ -49,10 +49,11 @@
 // v0.2.5 - added raise warning when key is not found.
 // v0.2.6 - fixed a bug in the resizing of string buffers.
 // v0.2.7 - improved parse_file error reporting with specific system errors and file name.
+// v0.2.8 - conformed empty input parsing to RFC specifications (returns nullptr / throws instead of empty string).
 static const short TJ_VERSION_MAJOR = 0;
 static const short TJ_VERSION_MINOR = 2;
-static const short TJ_VERSION_PATCH = 7;
-static const char TJ_VERSION_STRING[] = "0.2.7";
+static const short TJ_VERSION_PATCH = 8;
+static const char TJ_VERSION_STRING[] = "0.2.8";
 
 #ifndef TJ_USE_CHAR
 #  define TJ_USE_CHAR 1

tests/testtinyjson.cpp

@@ -352,29 +352,23 @@ TEST(TestBasic, NullInStringIsValid) {
   delete json;
 }
 
-TEST(TestBasic, NothingIsJustAnEmptyString) {
+TEST(TestBasic, EmptyStringReturnsNull) {
   auto json = TinyJSON::TJ::parse("");
-  ASSERT_NE(nullptr, json);
-  ASSERT_TRUE(json->is_string());
-  ASSERT_STREQ("", json->dump_string());
-
-  delete json;
+  ASSERT_EQ(nullptr, json);
 }
 
-TEST(TestBasic, NothingIsJustAnEmptyStringWithSpaces) {
+TEST(TestBasic, WhitespaceOnlyStringReturnsNull) {
   auto json = TinyJSON::TJ::parse(R"(   
 
 
 
 
 
 
-)");
-  ASSERT_NE(nullptr, json);
-  ASSERT_TRUE(json->is_string());
-  ASSERT_STREQ("", json->dump_string());
 
-  delete json;
+
+)");
+  ASSERT_EQ(nullptr, json);
 }
 
 TEST(TestBasic, StringValueIsValid) {
@@ -563,6 +557,14 @@ TEST(TestBasic, ArrayIsValid) {
   ASSERT_TRUE(TinyJSON::TJ::is_valid("[12,13,14]"));
 }
 
+TEST(TestBasic, EmptyStringIsNotValid) {
+  ASSERT_FALSE(TinyJSON::TJ::is_valid(""));
+}
+
+TEST(TestBasic, WhitespaceOnlyIsNotValid) {
+  ASSERT_FALSE(TinyJSON::TJ::is_valid("   \t\r\n   "));
+}
+
 TEST(TestBasic, UserLiteralsArray)
 {
   using namespace TinyJSON;