KT-729 Need to support arrays as varargs

compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java

@@ -1529,15 +1529,55 @@ public class ExpressionCodegen extends JetVisitor<StackValue, StackValue> {
         Type type = asmType(outType);
         assert type.getSort() == Type.ARRAY;
         Type elementType = correctElementType(type);
-        int size = valueArgument.getArguments().size();
+        List<ValueArgument> arguments = valueArgument.getArguments();
+        int size = arguments.size();
 
-        v.iconst(valueArgument.getArguments().size());
-        v.newarray(elementType);
+        boolean hasSpread = false;
         for(int i = 0; i != size; ++i) {
-            v.dup();
-            v.iconst(i);
-            gen(valueArgument.getArguments().get(i).getArgumentExpression(), elementType);
-            StackValue.arrayElement(elementType, false).store(v);
+            if(arguments.get(i).getSpreadElement() != null) {
+                hasSpread = true;
+                break;
+            }
+        }
+
+        if(hasSpread) {
+            if(size == 1) {
+                gen(arguments.get(0).getArgumentExpression(), type);
+            }
+            else {
+                String owner = "jet/runtime/Intrinsics$SpreadBuilder";
+                v.anew(Type.getObjectType(owner));
+                v.dup();
+                v.invokespecial(owner, "<init>", "()V");
+                for(int i = 0; i != size; ++i) {
+                    v.dup();
+                    ValueArgument argument = arguments.get(i);
+                    if(argument.getSpreadElement() != null) {
+                        gen(argument.getArgumentExpression(),JetTypeMapper.TYPE_OBJECT);
+                        v.invokevirtual(owner, "addSpread", "(Ljava/lang/Object;)V");
+                    }
+                    else {
+                        gen(argument.getArgumentExpression(), elementType);
+                        v.invokevirtual(owner, "add", "(Ljava/lang/Object;)Z");
+                        v.pop();
+                    }
+                }
+                v.dup();
+                v.invokevirtual(owner, "size", "()I");
+                v.newarray(elementType);
+                v.invokevirtual(owner, "toArray", "([Ljava/lang/Object;)[Ljava/lang/Object;");
+                v.checkcast(type);
+            }
+        }
+        else {
+            v.iconst(arguments.size());
+            v.newarray(elementType);
+            for(int i = 0; i != size; ++i) {
+                v.dup();
+                v.iconst(i);
+                gen(arguments.get(i).getArgumentExpression(), elementType);
+                StackValue.arrayElement(elementType, false).store(v);
+            }
         }
     }
 

compiler/backend/src/org/jetbrains/jet/codegen/JetTypeMapper.java

@@ -54,6 +54,7 @@ public class JetTypeMapper {
     public static final Type TYPE_NOTHING = Type.getObjectType("jet/Nothing");
     public static final Type JL_NUMBER_TYPE = Type.getObjectType("java/lang/Number");
     public static final Type JL_STRING_BUILDER = Type.getObjectType("java/lang/StringBuilder");
+    public static final Type JL_ARRAY_LIST = Type.getObjectType("java/util/ArrayList");
     public static final Type JL_STRING_TYPE = Type.getObjectType("java/lang/String");
     public static final Type JL_CHAR_SEQUENCE_TYPE = Type.getObjectType("java/lang/CharSequence");
     private static final Type JL_COMPARABLE_TYPE = Type.getObjectType("java/lang/Comparable");

compiler/tests/org/jetbrains/jet/codegen/VarArgTest.java

@@ -16,8 +16,10 @@
 
 package org.jetbrains.jet.codegen;
 
+import java.lang.reflect.Array;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.util.Arrays;
 
 /**
  * @author alex.tkachman
@@ -94,4 +96,23 @@ public class VarArgTest extends CodegenTestCase {
     public void testKt797() {
         blackBoxFile("regressions/kt796_797.jet");
     }
+
+    public void testArrayAsVararg () throws InvocationTargetException, IllegalAccessException {
+        loadText("private fun asList(vararg elems: String) = elems; fun test(ts: Array<String>) = asList(*ts); ");
+        //System.out.println(generateToText());
+        final Method main = generateFunction("test");
+        String[] args = {"mama", "papa"};
+        assertTrue(args == main.invoke(null, new Object[]{ args } ));
+    }
+
+    public void testArrayAsVararg2 () throws InvocationTargetException, IllegalAccessException {
+        loadText("private fun asList(vararg elems: String) = elems; fun test(ts1: Array<String>, ts2: String) = asList(*ts1, ts2); ");
+        System.out.println(generateToText());
+        final Method main = generateFunction("test");
+        Object invoke = main.invoke(null, new Object[] {new String[] {"mama"}, "papa" });
+        assertInstanceOf(invoke, String[].class);
+        assertEquals(2, Array.getLength(invoke));
+        assertEquals("mama", Array.get(invoke, 0));
+        assertEquals("papa", Array.get(invoke, 1));
+    }
 }

runtime/src/jet/runtime/Intrinsics.java

@@ -19,6 +19,8 @@ package jet.runtime;
 import jet.Function0;
 
 import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Iterator;
 
 /**
  * @author alex.tkachman
@@ -82,4 +84,36 @@ public class Intrinsics {
             return sanitizeStackTrace(this);
         }
     }
+
+    public static class SpreadBuilder extends ArrayList {
+        public void addSpread(Object array) {
+            if(array != null) {
+                if(array instanceof Object[]) {
+                    Object[] arr = (Object[]) array;
+                    if(arr.length > 0) {
+                        ensureCapacity(size() + arr.length);
+                        for (int i = 0; i < arr.length; i++) {
+                            add(arr[i]);
+                        }
+                    }
+                }
+                else if(array instanceof Collection) {
+                    addAll((Collection) array);
+                }
+                else if(array instanceof Iterable) {
+                    for(Iterator iterator = ((Iterable) array).iterator(); iterator.hasNext(); ) {
+                        add(iterator.next());
+                    }
+                }
+                else if(array instanceof Iterator) {
+                    for(Iterator iterator = ((Iterator) array); iterator.hasNext(); ) {
+                        add(iterator.next());
+                    }
+                }
+                else {
+                    throw new UnsupportedOperationException("Don't know how to spread " + array.getClass());
+                }
+            }
+        }
+    }
 }