Improve error reporting.

src/core/org/luaj/lib/BaseLib.java

@@ -364,7 +364,7 @@ public class BaseLib extends LFunction {
 			break;
 		}
 		default:
-			luaUnsupportedOperation();
+			throw new RuntimeException( "bad id: "+id );
 		}
 		return false;
 	}

src/core/org/luaj/lib/CoroutineLib.java

@@ -126,7 +126,7 @@ public class CoroutineLib extends LFunction {
 				if ( vm.toboolean(1) )
 					vm.remove(1);
 				else
-					vm.error( vm.tostring(2), 0 );
+					vm.error( vm.tostring(2) );
 				return false;
 			}
 		}

src/core/org/luaj/lib/MathLib.java

@@ -113,7 +113,7 @@ public class MathLib extends LFunction {
 			setResult( vm, LInteger.valueOf( (int) Math.floor( vm.tonumber(2) ) ) );
 			break;
 		default:
-			luaUnsupportedOperation();
+			throw new RuntimeException( "bad id: "+id );
 		}
 		return false;
 	}

src/core/org/luaj/lib/PackageLib.java

@@ -144,7 +144,7 @@ public class PackageLib extends LFunction {
 			break;
 		}
 		default:
-			luaUnsupportedOperation();
+			throw new RuntimeException( "bad id: "+id );
 		}
 		return false;
 	}
@@ -182,7 +182,7 @@ public class PackageLib extends LFunction {
 		    /* try global variable (and create one if it does not exist) */
 			module = findtable( vm._G, modname );
 			if ( module == null )
-				vm.error( "name conflict for module '"+modname+"'", 2 );
+				vm.error( "name conflict for module '"+modname+"'" );
 			LOADED.luaSetTable(vm, LOADED, modname, module);
 		} else {
 			module = (LTable) value;

src/core/org/luaj/lib/StringLib.java

@@ -135,7 +135,7 @@ public class StringLib extends LFunction {
 			break;
 			
 		default:
-			luaUnsupportedOperation();
+			vm.error( "bad id" );
 		}
 		return false;
 	}

src/core/org/luaj/lib/TableLib.java

@@ -175,7 +175,7 @@ public class TableLib extends LFunction {
 		}
 			
 		default:
-			luaUnsupportedOperation();
+			throw new RuntimeException( "bad id" );
 		}
 		return false;
 	}

src/core/org/luaj/vm/LDouble.java

@@ -77,26 +77,28 @@ public class LDouble extends LNumber {
 		case Lua.OP_MUL: return new LDouble( lhs * rhs );
 		case Lua.OP_DIV: return new LDouble( lhs / rhs );
 		case Lua.OP_MOD: return new LDouble( lhs - Math.floor(lhs/rhs) * rhs );
-		// case Lua.OP_POW: return new LDouble( dpow(lhs, rhs) );
+		case Lua.OP_POW: throw new LuaErrorException("math.pow() not implemented for doubles");
 		}
-		return luaUnsupportedOperation();
+		throw new RuntimeException("bad opcode");
 	}
 
-	/*
+	/* warning: NOT TESTED
 	public static double dpow(double a, double b) {
 		if ( b < 0 )
 			return 1 / dpow( a, -b );
-		int p = 1;
+		double p = 1;
 		int whole = (int) b;
-		for ( double v=a; whole > 0; whole>>=1, v=v*v )
+		for ( double v=a; whole > 0; whole>>=1, v*=v )
 			if ( (whole & 1) != 0 )
 				p *= v;
+		if ( (b -= whole) > 0 ) {
 			int frac = (int) (0x10000 * b);
 			for ( ; (frac&0xffff)!=0; frac<<=1 ) {
 				a = Math.sqrt(a);
 				if ( (frac & 0x8000) != 0 )
 					p *= a;
 			}
+		}
 		return p;
 	}
 	*/
@@ -132,8 +134,7 @@ public class LDouble extends LNumber {
 		case Lua.OP_LT: return lhs < rhs;
 		case Lua.OP_LE: return lhs <= rhs;
 		}
-		luaUnsupportedOperation();
+		throw new RuntimeException("bad opcode");
-		return false;
 	}
 
 	/** Arithmetic negative */

src/core/org/luaj/vm/LInteger.java

@@ -85,7 +85,7 @@ public class LInteger extends LNumber {
 		case Lua.OP_MOD: return LInteger.valueOf( m_value - ((int) Math.floor(m_value/(double)rhs)) * rhs );
 		case Lua.OP_POW: return LInteger.valueOf( ipow(m_value, rhs) );
 		}
-		return luaUnsupportedOperation();
+		throw new RuntimeException("bad opcode");
 	}
 	
 	private static int ipow(int v, int rhs) {
@@ -113,8 +113,7 @@ public class LInteger extends LNumber {
 		case Lua.OP_LT: return m_value < rhs;
 		case Lua.OP_LE: return m_value <= rhs;
 		}
-		luaUnsupportedOperation();
+		throw new RuntimeException("bad opcode");
-		return false;
 	}
 	
 	// unsupported except for numbers

src/core/org/luaj/vm/LString.java

@@ -315,8 +315,7 @@ public class LString extends LValue {
 		case Lua.OP_LT: return compareTo(rhs) < 0;
 		case Lua.OP_LE: return compareTo(rhs) <= 0;
 		}
-		luaUnsupportedOperation();
+		throw new RuntimeException("bad opcode");
-		return false;
 	}
 	
 	public LValue luaBinOpDouble( int opcode, double m_value ) {

src/core/org/luaj/vm/LValue.java

@@ -31,14 +31,21 @@ public class LValue {
 	/** Metatable tag for intercepting table sets */
 	public static final LString TM_NEWINDEX = new LString("__newindex");
 	
-	protected static LValue luaUnsupportedOperation() {
+	protected void conversionError(String target) {
-		throw new LuaErrorException( "not supported" );
-	}
-
-	protected void luaConversionError(String target) {
 		throw new LuaErrorException( "bad conversion: "+luaGetTypeName()+" to "+target );
 	}
 
+	private static LValue arithmeticError( Object type ) {
+		throw new LuaErrorException( "attempt to perform arithmetic on ? (a "+type+" value)" );
+	}
+
+	protected static LValue compareError( Object typea, Object typeb ) {
+		throw new LuaErrorException( "attempt to compare "+typea+" with "+typeb );
+	}
+
+	private void indexError(LuaState vm, LValue nontable) {
+		vm.error( "attempt to index ? (a "+nontable.luaGetTypeName()+" value)", 2 );
+	}
 
 	public String id() {
 		return Integer.toHexString(hashCode());
@@ -58,24 +65,24 @@ public class LValue {
 
 	// unsupported except for numbers
 	public LValue luaBinOpUnknown(int opcode, LValue lhs) {
-		return luaUnsupportedOperation();
+		return arithmeticError(lhs.luaGetTypeName());
 	}
 
 	// unsupported except for numbers
 	public LValue luaBinOpInteger(int opcode, int m_value) {
-		return luaUnsupportedOperation();
+		return arithmeticError("number");
 	}
 
 	// unsupported except for numbers
 	public LValue luaBinOpDouble(int opcode, double m_value) {
-		return luaUnsupportedOperation();
+		return arithmeticError("number");
 	}
 
 	// unsupported except for numbers, strings, and == with various combinations of Nil, Boolean, etc. 
 	public boolean luaBinCmpUnknown(int opcode, LValue lhs) {
 		if ( opcode == Lua.OP_EQ )
 			return lhs == this;
-		luaUnsupportedOperation();
+		compareError(lhs.luaGetTypeName(), luaGetTypeName());
 		return false;
 	}
 	
@@ -83,7 +90,7 @@ public class LValue {
 	public boolean luaBinCmpString(int opcode, LString rhs) {
 		if ( opcode == Lua.OP_EQ )
 			return false;
-		luaUnsupportedOperation();
+		compareError(luaGetTypeName(), "string");
 		return false;
 	}
 	
@@ -91,7 +98,7 @@ public class LValue {
 	public boolean luaBinCmpInteger(int opcode, int rhs) {
 		if ( opcode == Lua.OP_EQ )
 			return false;
-		luaUnsupportedOperation();
+		compareError(luaGetTypeName(), "number");
 		return false;
 	}
 	
@@ -99,7 +106,7 @@ public class LValue {
 	public boolean luaBinCmpDouble(int opcode, double rhs) {
 		if ( opcode == Lua.OP_EQ )
 			return false;
-		luaUnsupportedOperation();
+		compareError(luaGetTypeName(), "number");
 		return false;
 	}
 	
@@ -119,7 +126,7 @@ public class LValue {
 				return;
 			}
 		}
-		vm.pushnil();
+		indexError( vm, table );
 	}
 	
 	/** Get a value from a table 
@@ -136,7 +143,7 @@ public class LValue {
 				return;
 			}
 		}
-		vm.error( "attempt to index ? (a "+table.luaGetTypeName()+" value)", 2 );
+		indexError( vm, table );
 	}
 	
 	/** Get the value as a LString 
@@ -152,20 +159,12 @@ public class LValue {
 	
 	/** Arithmetic negative */
 	public LValue luaUnaryMinus() {
-		return luaUnsupportedOperation();
+		return arithmeticError(luaGetTypeName());
 	}
 
 	/** Built-in opcode LEN, for Strings and Tables */
 	public int luaLength() {
-		// TODO: call meta-method TM_LEN here
+		throw new LuaErrorException( "attempt to get length of ? (a "+luaGetTypeName()+" value)" );
-		luaUnsupportedOperation();
-		return 0;
-	}
-
-	/** Valid for tables 
-	 * @param isPairs true to iterate over non-integers as well */
-	public LValue luaPairs(boolean isPairs) {
-		return luaUnsupportedOperation();
 	}
 
 	/**
@@ -184,7 +183,7 @@ public class LValue {
 
 	/** Valid for tables */
 	public void luaSetMetatable(LValue metatable) {
-		luaUnsupportedOperation();
+		throw new LuaErrorException( "bad argument #1 to 'setmetatable' (table expected, got "+metatable.luaGetTypeName()+")");
 	}
 
 	/** Valid for all types: return the int value identifying the type of this value */
@@ -229,7 +228,7 @@ public class LValue {
 
 	/** Return value as an integer */
 	public int toJavaInt() {
-		luaConversionError("number");
+		conversionError("number");
 		return 0;
 	}
 
@@ -245,55 +244,55 @@ public class LValue {
 
 	/** Convert to a Boolean value */
 	public Boolean toJavaBoxedBoolean() {
-		luaConversionError("Boolean");
+		conversionError("Boolean");
 		return null;
 	}
 
 	/** Convert to a Byte value */
 	public Byte toJavaBoxedByte() {
-		luaConversionError("Byte");
+		conversionError("Byte");
 		return null;
 	}
 
 	/** Convert to a boxed Character value */
 	public Character toJavaBoxedCharacter() {
-		luaConversionError("Character");
+		conversionError("Character");
 		return null;
 	}
 
 	/** Convert to a boxed Double value */
 	public Double toJavaBoxedDouble() {
-		luaConversionError("Double");
+		conversionError("Double");
 		return null;
 	}
 
 	/** Convert to a boxed Float value */
 	public Float toJavaBoxedFloat() {
-		luaConversionError("Float");
+		conversionError("Float");
 		return null;
 	}
 
 	/** Convert to a boxed Integer value */
 	public Integer toJavaBoxedInteger() {
-		luaConversionError("Integer");
+		conversionError("Integer");
 		return null;
 	}
 
 	/** Convert to a boxed Long value */
 	public Long toJavaBoxedLong() {
-		luaConversionError("Long");
+		conversionError("Long");
 		return null;
 	}
 
 	/** Convert to a boxed Short value */
 	public Short toJavaBoxedShort() {
-		luaConversionError("Short");
+		conversionError("Short");
 		return null;
 	}
 
 	/** Convert to a Java Object iff this is a LUserData value */
 	public Object toJavaInstance() {
-		luaConversionError("instance");
+		conversionError("instance");
 		return null;
 	}
 

src/core/org/luaj/vm/LuaErrorException.java

@@ -36,7 +36,15 @@ public class LuaErrorException extends RuntimeException {
 	 * Construct a LuaErrorException with the default message. 
 	 */
 	public LuaErrorException() {
-		super(DEFAULT_MESSAGE);
+		this(DEFAULT_MESSAGE);
+	}
+
+	/**
+	 * Construct a LuaErrorException in response to a Throwable that was caught
+	 * and with the default message. 
+	 */
+	public LuaErrorException(Throwable cause) {
+		this(DEFAULT_MESSAGE+": "+cause);
 	}
 
 	/**
@@ -45,14 +53,35 @@ public class LuaErrorException extends RuntimeException {
 	 * @param message message to supply
 	 */
 	public LuaErrorException(String message) {
-		super(message);
+		this(null, message, 1);
 	}
 
 	/**
-	 * Construct a LuaErrorException in response to a Throwable that was caught
+	 * Construct the message around a specific vm and with a particular level of debug info
-	 * and with the default message. 
+	 * @param vm
+	 * @param message
+	 * @param level
 	 */
-	public LuaErrorException(Throwable cause) {
+	public LuaErrorException(LuaState vm, String message, int level) {
-		super(DEFAULT_MESSAGE+": "+cause);
+		super( addLineInfo( vm, message, level ) );
+	}
+
+	/** 
+	 * Append line info as per level
+	 * @param vm
+	 * @param message
+	 * @param level
+	 * @return
+	 */
+	private static String addLineInfo(LuaState vm, String message, int level) {
+		if ( level < 1 )
+			return message;
+		if ( vm == null ) {
+			if ( LThread.running != null )
+				vm = LThread.running.threadVm;
+			else
+				vm = LuaState.mainState;
+		}
+		return vm.getFileLine(vm.cc + 1 - level) + ": " + message;
 	}
 }

src/core/org/luaj/vm/LuaState.java

@@ -96,7 +96,7 @@ public class LuaState extends Lua {
     protected Stack upvals = new Stack();
 	protected LFunction panic;
     
-	public static LTable DEFAULT_GLOBALS;
+	static LuaState mainState;
     public LTable _G;
 
     // main debug hook, overridden by DebugStackState
@@ -121,8 +121,9 @@ public class LuaState extends Lua {
 	 * @deprecated As of version 0.10, replaced by {@link #newState()}
 	 */
 	public LuaState() {
-		_G = DEFAULT_GLOBALS = new LTable();
+		_G = new LTable();
 		_G.put("_G", _G);
+		mainState = this;
 	}
 
 	/** 
@@ -1004,13 +1005,13 @@ public class LuaState extends Lua {
     
     /** 
      * Get the file line number info for a particular call frame.
-     * @param cindex
+     * @param cindex index into call stack
      * @return
      */
     protected String getFileLine(int cindex) {
         String source = "?";
         String line = "";
-        if (cindex >= 0) {
+        if (cindex >= 0 && cindex <= cc) {
             CallInfo call = this.calls[cindex];
             LPrototype p = call.closure.p;
             if (p != null && p.source != null)
@@ -1041,18 +1042,14 @@ public class LuaState extends Lua {
 	 * after filling line number information first when level > 0.
 	 */
     public void error(String message, int level) {
-    	if ( level > 1 )
+        throw new LuaErrorException( this, message, level );
-    		message = getFileLine(cc + 2 - level) + ": " + message;
-        throw new LuaErrorException( message );
     }
     
 	/**
 	 * Raises an error with the default level.   
-	 * 
-	 * In the java implementation this calls error(message,1)
 	 */
     public void error(String message) {
-    	error( message, 1 );
+    	throw new LuaErrorException( this, message, 1 );
     }
     
 	/**
@@ -1065,9 +1062,7 @@ public class LuaState extends Lua {
 	 * 
 	 */
 	public void error() {
-		String message = tostring(-1);
+		throw new LuaErrorException( this, tostring(-1), 0);
-		// pop(1);
-		error( message );
 	}
 	
 	/**

src/j2se/org/luaj/lib/j2se/LuajavaLib.java

@@ -109,7 +109,7 @@ public final class LuajavaLib extends LFunction {
 			}
 			break;
 		default:
-			luaUnsupportedOperation();
+			throw new LuaErrorException("not yet supported: "+this);
 		}
 		return false;
 	}

src/test/java/org/luaj/vm/LuaJTest.java

@@ -70,6 +70,10 @@ public class LuaJTest extends TestCase {
 		runTest( "compare" );
 	}
 
+	public void testErrors() throws IOException, InterruptedException {
+		runTest( "errors" );
+	}
+
 	public void testMathLib() throws IOException, InterruptedException {
 		runTest( "mathlib" );
 	}
@@ -129,7 +133,7 @@ public class LuaJTest extends TestCase {
 	public void testUpvalues2() throws IOException, InterruptedException {
 		runTest( "upvalues2" );
 	}
-
+//*/
 	private void runTest( String testName ) throws IOException, InterruptedException {
 
 		// new lua state 

src/test/res/errors.lua

@@ -0,0 +1,88 @@
+-- object ids
+require 'ids'
+ids = {}
+
+-- test of common types of errors
+local function c(f,...) return f(...) end
+local function b(...) return c(...) end
+local function a(...) return pcall(b,...) end
+s = 'some string'
+local t = {}
+
+-- error message tests
+print( 'a(error)', a(error) )
+print( 'a(error,"msg")', a(error,"msg") )
+print( 'a(error,"msg",0)', a(error,"msg",0) )
+print( 'a(error,"msg",1)', a(error,"msg",1) )
+print( 'a(error,"msg",2)', a(error,"msg",2) )
+print( 'a(error,"msg",3)', a(error,"msg",3) )
+print( 'a(error,"msg",4)', a(error,"msg",4) )
+print( 'a(error,"msg",5)', a(error,"msg",5) )
+print( 'a(error,"msg",6)', a(error,"msg",6) )
+
+-- call errors
+print( 'a(nil())', a(function() return n() end) )
+print( 'a(t())  ', a(function() return t() end) )
+print( 'a(s())  ', a(function() return s() end) )
+print( 'a(true())', a(function() local b = true; return b() end) )
+
+-- arithmetic errors
+print( 'a(nil+1)', a(function() return nil+1 end) )
+print( 'a(a+1)  ', a(function() return a+1 end) )
+print( 'a(s+1)  ', a(function() return s+1 end) )
+print( 'a(true+1)', a(function() local b = true; return b+1 end) )
+
+-- table errors
+print( 'a(nil.x)', a(function() return n.x end) )
+print( 'a(a.x)  ', a(function() return a.x end) )
+print( 'a(s.x)  ', a(function() return s.x end) )
+print( 'a(true.x)', a(function() local b = true; return b.x end) )
+print( 'a(nil.x=5)', a(function() n.x=5 end) )
+print( 'a(a.x=5)  ', a(function() a.x=5 end) )
+print( 'a(s.x=5)  ', a(function() s.x=5 end) )
+print( 'a(true.x=5)', a(function() local b = true; b.x=5 end) )
+
+-- len operator 
+print( 'a(#nil) ', a(function() return #n end) )
+print( 'a(#t)   ', a(function() return #t end) )
+print( 'a(#s)   ', a(function() return #s end) )
+print( 'a(#a)   ', a(function() return #a end) )
+print( 'a(#true)', a(function() local b = true; return #b end) )
+
+-- comparison errors
+print( 'a(nil>1)', a(function() return nil>1 end) )
+print( 'a(a>1)  ', a(function() return a>1 end) )
+print( 'a(s>1)  ', a(function() return s>1 end) )
+print( 'a(true>1)', a(function() local b = true; return b>1 end) )
+
+-- unary minus errors
+print( 'a(-nil)', a(function() return -n end) )
+print( 'a(-a)  ', a(function() return -a end) )
+print( 'a(-s)  ', a(function() return -s end) )
+print( 'a(-true)', a(function() local b = true; return -b end) )
+
+-- pairs
+print( 'a(pairs(nil))', a(function() return id(pairs(nil,{})) end) )
+print( 'a(pairs(a))  ', a(function() return id(pairs(a,{})) end) )
+print( 'a(pairs(s))  ', a(function() return id(pairs(s,{})) end) )
+print( 'a(pairs(t))  ', a(function() return id(pairs(t,{})) end) )
+print( 'a(pairs(true))', a(function() local b = true; return id(pairs(b,{})) end) )
+
+-- setmetatable
+function sm(...)
+	return id(setmetatable(...))
+end
+print( 'a(setmetatable(nil))', a(function() return sm(nil,{}) end) )
+print( 'a(setmetatable(a))  ', a(function() return sm(a,{}) end) )
+print( 'a(setmetatable(s))  ', a(function() return sm(s,{}) end) )
+print( 'a(setmetatable(true))', a(function() local b = true; return sm(b,{}) end) )
+print( 'a(setmetatable(t))  ', a(function() return sm(t,{}) end) )
+print( 'a(setmetatable(t*))  ', a(function() return sm(t,{__metatable={}}) end) )
+print( 'a(setmetatable(t))  ', a(function() return sm(t,{}) end) )
+t = {}
+print( 'a(setmetatable(t))  ', a(function() return sm(t,{}) end) )
+print( 'a(setmetatable(t*))  ', a(function() return sm(t,{__metatable='some string'}) end) )
+print( 'a(setmetatable(t))  ', a(function() return sm(t,{}) end) )
+
+-- bad args to error!
+print( 'error("msg","arg")', a(function() error('some message', 'some bad arg') end) )

src/test/res/ids.lua

@@ -0,0 +1,14 @@
+-- utility to give tables and functions uniform ids for testing
+ids = {}
+function id(obj)
+	if not obj or type(obj) == 'number' or type(obj) == 'string' or type(obj) == 'boolean' then
+		return obj
+	end
+	local v = ids[obj]
+	if v then
+		return v
+	end
+	table.insert(ids,obj)
+	ids[obj] = type(obj)..'.'..tostring(#ids)
+	return ids[obj]
+end