improve error reporting

bytecode.go

@@ -7,46 +7,46 @@ package luajit
 #include <string.h>
 
 typedef struct {
-    const unsigned char *buf;
+	const unsigned char *buf;
-    size_t size;
+	size_t size;
-    const char *name;
+	const char *name;
 } BytecodeReader;
 
 const char *bytecode_reader(lua_State *L, void *ud, size_t *size) {
-    BytecodeReader *r = (BytecodeReader *)ud;
+	BytecodeReader *r = (BytecodeReader *)ud;
-    (void)L;  // unused
+	(void)L;  // unused
-    if (r->size == 0) return NULL;
+	if (r->size == 0) return NULL;
-    *size = r->size;
+	*size = r->size;
-    r->size = 0;  // Only read once
+	r->size = 0;  // Only read once
-    return (const char *)r->buf;
+	return (const char *)r->buf;
 }
 
 int load_bytecode(lua_State *L, const unsigned char *buf, size_t len, const char *name) {
-    BytecodeReader reader = {buf, len, name};
+	BytecodeReader reader = {buf, len, name};
-    return lua_load(L, bytecode_reader, &reader, name);
+	return lua_load(L, bytecode_reader, &reader, name);
 }
 
 // Direct bytecode dumping without intermediate buffer - more efficient
 int direct_bytecode_writer(lua_State *L, const void *p, size_t sz, void *ud) {
-    void **data = (void **)ud;
+	void **data = (void **)ud;
-    size_t current_size = (size_t)data[1];
+	size_t current_size = (size_t)data[1];
-    void *newbuf = realloc(data[0], current_size + sz);
+	void *newbuf = realloc(data[0], current_size + sz);
-    if (newbuf == NULL) return 1;
+	if (newbuf == NULL) return 1;
 
-    memcpy((unsigned char*)newbuf + current_size, p, sz);
+	memcpy((unsigned char*)newbuf + current_size, p, sz);
-    data[0] = newbuf;
+	data[0] = newbuf;
-    data[1] = (void*)(current_size + sz);
+	data[1] = (void*)(current_size + sz);
-    return 0;
+	return 0;
 }
 
 // Combined load and run bytecode in a single call
 int load_and_run_bytecode(lua_State *L, const unsigned char *buf, size_t len,
                          const char *name, int nresults) {
-    BytecodeReader reader = {buf, len, name};
+	BytecodeReader reader = {buf, len, name};
-    int status = lua_load(L, bytecode_reader, &reader, name);
+	int status = lua_load(L, bytecode_reader, &reader, name);
-    if (status != 0) return status;
+	if (status != 0) return status;
 
-    return lua_pcall(L, 0, nresults, 0);
+	return lua_pcall(L, 0, nresults, 0);
 }
 */
 import "C"
@@ -102,10 +102,7 @@ func (s *State) LoadBytecode(bytecode []byte, name string) error {
 	)
 
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), fmt.Sprintf("LoadBytecode(%s)", name))
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return err
 	}
@@ -123,10 +120,7 @@ func (s *State) RunBytecode() error {
 func (s *State) RunBytecodeWithResults(nresults int) error {
 	status := C.lua_pcall(s.L, 0, C.int(nresults), 0)
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), fmt.Sprintf("RunBytecode(nresults=%d)", nresults))
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return err
 	}
@@ -152,10 +146,7 @@ func (s *State) LoadAndRunBytecode(bytecode []byte, name string) error {
 	)
 
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), fmt.Sprintf("LoadAndRunBytecode(%s)", name))
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return err
 	}
@@ -182,10 +173,7 @@ func (s *State) LoadAndRunBytecodeWithResults(bytecode []byte, name string, nres
 	)
 
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), fmt.Sprintf("LoadAndRunBytecodeWithResults(%s, nresults=%d)", name, nresults))
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return err
 	}

stack.go

@@ -5,16 +5,45 @@ package luajit
 #include <lauxlib.h>
 */
 import "C"
-import "fmt"
+import (
+	"fmt"
+	"strings"
+)
 
-// LuaError represents an error from the Lua state
+// LuaError represents an enhanced error from the Lua state
 type LuaError struct {
-	Code    int
+	Code       int
-	Message string
+	Message    string
+	File       string
+	Line       int
+	StackTrace string
+	Context    string
 }
 
 func (e *LuaError) Error() string {
-	return fmt.Sprintf("lua error (code=%d): %s", e.Code, e.Message)
+	var parts []string
+
+	if e.File != "" && e.Line > 0 {
+		parts = append(parts, fmt.Sprintf("%s:%d", e.File, e.Line))
+	}
+
+	if e.Context != "" {
+		parts = append(parts, fmt.Sprintf("[%s]", e.Context))
+	}
+
+	parts = append(parts, e.Message)
+
+	if e.Code != 0 {
+		parts = append(parts, fmt.Sprintf("(code=%d)", e.Code))
+	}
+
+	result := strings.Join(parts, " ")
+
+	if e.StackTrace != "" {
+		result += "\n" + e.StackTrace
+	}
+
+	return result
 }
 
 // Stack management constants from lua.h
@@ -45,3 +74,50 @@ func (s *State) GetStackTrace() string {
 
 	return trace
 }
+
+// GetErrorInfo extracts detailed error information from the Lua stack
+func (s *State) GetErrorInfo(context string) *LuaError {
+	if s.GetTop() == 0 {
+		return &LuaError{
+			Message: "unknown error (empty stack)",
+			Context: context,
+		}
+	}
+
+	message := s.ToString(-1)
+
+	// Parse file:line from common Lua error format
+	var file string
+	var line int
+
+	if colonPos := strings.Index(message, ":"); colonPos > 0 {
+		beforeColon := message[:colonPos]
+		afterColon := message[colonPos+1:]
+
+		if secondColonPos := strings.Index(afterColon, ":"); secondColonPos > 0 {
+			file = beforeColon
+			if n, err := fmt.Sscanf(afterColon[:secondColonPos], "%d", &line); n == 1 && err == nil {
+				// Strip the file:line part from message for cleaner display
+				message = strings.TrimSpace(afterColon[secondColonPos+1:])
+			}
+		}
+	}
+
+	// Get stack trace
+	stackTrace := s.GetStackTrace()
+
+	return &LuaError{
+		Message:    message,
+		File:       file,
+		Line:       line,
+		StackTrace: stackTrace,
+		Context:    context,
+	}
+}
+
+// CreateLuaError creates a LuaError with full context information
+func (s *State) CreateLuaError(code int, context string) *LuaError {
+	err := s.GetErrorInfo(context)
+	err.Code = code
+	return err
+}

wrapper.go

@@ -13,25 +13,25 @@ package luajit
 
 // Direct execution helpers to minimize CGO transitions
 static int do_string(lua_State *L, const char *s) {
-    int status = luaL_loadstring(L, s);
+	int status = luaL_loadstring(L, s);
-    if (status == 0) {
+	if (status == 0) {
-        status = lua_pcall(L, 0, 0, 0);
+		status = lua_pcall(L, 0, 0, 0);
-    }
+	}
-    return status;
+	return status;
 }
 
 static int do_file(lua_State *L, const char *filename) {
-    int status = luaL_loadfile(L, filename);
+	int status = luaL_loadfile(L, filename);
-    if (status == 0) {
+	if (status == 0) {
-        status = lua_pcall(L, 0, 0, 0);
+		status = lua_pcall(L, 0, 0, 0);
-    }
+	}
-    return status;
+	return status;
 }
 
 static int execute_with_results(lua_State *L, const char *code, int store_results) {
-    int status = luaL_loadstring(L, code);
+	int status = luaL_loadstring(L, code);
-    if (status != 0) return status;
+	if (status != 0) return status;
-    return lua_pcall(L, 0, store_results ? LUA_MULTRET : 0, 0);
+	return lua_pcall(L, 0, store_results ? LUA_MULTRET : 0, 0);
 }
 */
 import "C"
@@ -342,10 +342,7 @@ func (s *State) LoadString(code string) error {
 
 	status := C.luaL_loadstring(s.L, ccode)
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), "LoadString")
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return err
 	}
@@ -359,10 +356,7 @@ func (s *State) LoadFile(filename string) error {
 
 	status := C.luaL_loadfile(s.L, cfilename)
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), fmt.Sprintf("LoadFile(%s)", filename))
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return err
 	}
@@ -373,10 +367,7 @@ func (s *State) LoadFile(filename string) error {
 func (s *State) Call(nargs, nresults int) error {
 	status := C.lua_pcall(s.L, C.int(nargs), C.int(nresults), 0)
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), fmt.Sprintf("Call(%d,%d)", nargs, nresults))
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return err
 	}
@@ -390,10 +381,7 @@ func (s *State) DoString(code string) error {
 
 	status := C.do_string(s.L, ccode)
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), "DoString")
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return err
 	}
@@ -407,10 +395,7 @@ func (s *State) DoFile(filename string) error {
 
 	status := C.do_file(s.L, cfilename)
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), fmt.Sprintf("DoFile(%s)", filename))
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return err
 	}
@@ -426,10 +411,7 @@ func (s *State) Execute(code string) (int, error) {
 
 	status := C.execute_with_results(s.L, ccode, 1) // store_results=true
 	if status != 0 {
-		err := &LuaError{
+		err := s.CreateLuaError(int(status), "Execute")
-			Code:    int(status),
-			Message: s.ToString(-1),
-		}
 		s.Pop(1) // Remove error message
 		return 0, err
 	}