Pass user-supplied ScriptContext to script engine evaluation (fixes issue #21).

README.html

@@ -920,6 +920,7 @@ Files are no longer hosted at LuaForge.
 <li>Add sample code for Android Application that uses luaj.</li>
 <li>Add sample code for Applet that uses luaj.</li>
 <li>Fix balanced match for empty string (fixes issue #23).</li>
+<li>Pass user-supplied ScriptContext to script engine evaluation (fixes issue #21).</li>
 
 </ul></td></tr>
 </table></td></tr></table>

src/jse/org/luaj/vm2/script/LuaScriptEngine.java

@@ -95,6 +95,21 @@ public class LuaScriptEngine extends AbstractScriptEngine implements ScriptEngin
 		}
 	}
 
+	@Override
+	public Object eval(Reader reader, Bindings bindings) throws ScriptException {
+		return ((LuajCompiledScript) compile(reader)).eval(context.globals, bindings);
+	}
+
+	@Override
+	public Object eval(String script, Bindings bindings) throws ScriptException {
+		return eval(new StringReader(script), bindings);
+	}
+
+	@Override
+	protected ScriptContext getScriptContext(Bindings nn) {
+		throw new IllegalStateException("LuajScriptEngine should not be allocating contexts.");
+	}
+
 	@Override
 	public Bindings createBindings() {
 		return new SimpleBindings();
@@ -109,7 +124,7 @@ public class LuaScriptEngine extends AbstractScriptEngine implements ScriptEngin
 	@Override
 	public Object eval(Reader reader, ScriptContext context)
 			throws ScriptException {
-        return compile(reader).eval();
+        return compile(reader).eval(context);
 	}
 
 	@Override
@@ -142,7 +157,7 @@ public class LuaScriptEngine extends AbstractScriptEngine implements ScriptEngin
 	    	return eval(((LuajContext) context).globals, context.getBindings(ScriptContext.ENGINE_SCOPE));
 		}
 	    
-	    private Object eval(Globals g, Bindings b) throws ScriptException {
+	    Object eval(Globals g, Bindings b) throws ScriptException {
 	    	g.setmetatable(new BindingsMetatable(b));
 			LuaFunction f = function;
 			if (f.isclosure())

test/junit/org/luaj/vm2/script/ScriptEngineTests.java

@@ -28,6 +28,7 @@ import java.io.Reader;
 import javax.script.Bindings;
 import javax.script.Compilable;
 import javax.script.CompiledScript;
+import javax.script.ScriptContext;
 import javax.script.ScriptEngine;
 import javax.script.ScriptEngineFactory;
 import javax.script.ScriptEngineManager;
@@ -49,6 +50,7 @@ public class ScriptEngineTests extends TestSuite  {
 		suite.addTest( new TestSuite( SimpleBindingsTest.class,   "Simple Bindings" ) );
 		suite.addTest( new TestSuite( DefaultBindingsTest.class,   "Default Bindings" ) );
 		suite.addTest( new TestSuite( LuaJCBindingsTest.class,   "LuaJC Bindings" ) );
+		suite.addTest( new TestSuite( UserContextTest.class,   "User Context" ) );
 		return suite;
 	}
 	
@@ -245,4 +247,39 @@ public class ScriptEngineTests extends TestSuite  {
     		return "some-user-value";
     	}
     }
+
+	public static class UserContextTest extends TestCase {	
+		protected ScriptEngine e;
+		protected Bindings b;
+		protected ScriptContext c;
+		public void setUp() {
+	       	this.e = new ScriptEngineManager().getEngineByName("luaj");
+			this.c = new LuajContext();
+			this.b = c.getBindings(ScriptContext.ENGINE_SCOPE);
+		}
+		public void testUncompiledScript() throws ScriptException {
+            b.put("x", 144);
+            assertEquals(12, e.eval("z = math.sqrt(x); return z", b));
+            assertEquals(12, b.get("z"));
+            assertEquals(null, e.getBindings(ScriptContext.ENGINE_SCOPE).get("z"));
+            assertEquals(null, e.getBindings(ScriptContext.GLOBAL_SCOPE).get("z"));
+
+            b.put("x", 25);
+            assertEquals(5, e.eval("z = math.sqrt(x); return z", c));
+            assertEquals(5, b.get("z"));
+            assertEquals(null, e.getBindings(ScriptContext.ENGINE_SCOPE).get("z"));
+            assertEquals(null, e.getBindings(ScriptContext.GLOBAL_SCOPE).get("z"));
+		}
+		public void testCompiledScript() throws ScriptException {
+            CompiledScript cs = ((Compilable)e).compile("z = math.sqrt(x); return z");
+            
+            b.put("x", 144);
+            assertEquals(12, cs.eval(b));
+            assertEquals(12, b.get("z"));
+
+            b.put("x", 25);
+            assertEquals(5, cs.eval(c));
+            assertEquals(5, b.get("z"));
+		}
+	}
 }