Iterating over iterator.

js/js.tests/test/org/jetbrains/k2js/test/semantics/MiscTest.java

@@ -187,4 +187,12 @@ public final class MiscTest extends AbstractExpressionTest {
     public void testInheritFromJetIterator() throws Exception {
         fooBoxTest();
     }
+
+    public void testIterableExtension() throws Exception {
+        fooBoxTest();
+    }
+
+    public void testIterationOverIterator() throws Exception {
+        fooBoxTest();
+    }
 }

js/js.translator/src/org/jetbrains/k2js/translate/intrinsic/functions/factories/TopLevelFIF.java

@@ -16,12 +16,18 @@
 
 package org.jetbrains.k2js.translate.intrinsic.functions.factories;
 
+import com.google.dart.compiler.backend.js.ast.JsExpression;
 import com.google.dart.compiler.backend.js.ast.JsNameRef;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.jetbrains.k2js.translate.context.TranslationContext;
 import org.jetbrains.k2js.translate.intrinsic.functions.basic.BuiltInFunctionIntrinsic;
 import org.jetbrains.k2js.translate.intrinsic.functions.basic.CallStandardMethodIntrinsic;
+import org.jetbrains.k2js.translate.intrinsic.functions.basic.FunctionIntrinsic;
 import org.jetbrains.k2js.translate.intrinsic.functions.patterns.NamePredicate;
 
+import java.util.List;
+
 import static org.jetbrains.k2js.translate.intrinsic.functions.patterns.PatternBuilder.pattern;
 
 /**
@@ -31,6 +37,19 @@ public final class TopLevelFIF extends CompositeFIF {
     @NotNull
     public static final CallStandardMethodIntrinsic EQUALS = new CallStandardMethodIntrinsic(new JsNameRef("equals", "Kotlin"), true, 1);
     @NotNull
+    public static final FunctionIntrinsic RETURN_RECEIVER_INTRINSIC = new FunctionIntrinsic() {
+        @NotNull
+        @Override
+        public JsExpression apply(
+                @Nullable JsExpression receiver,
+                @NotNull List<JsExpression> arguments,
+                @NotNull TranslationContext context
+        ) {
+            assert receiver != null;
+            return receiver;
+        }
+    };
+    @NotNull
     public static final FunctionIntrinsicFactory INSTANCE = new TopLevelFIF();
 
     private TopLevelFIF() {
@@ -39,5 +58,6 @@ public final class TopLevelFIF extends CompositeFIF {
         add(pattern(NamePredicate.PRIMITIVE_NUMBERS, "equals"), EQUALS);
         add(pattern("String|Boolean|Char|Number.equals"), EQUALS);
         add(pattern("arrayOfNulls"), new CallStandardMethodIntrinsic(new JsNameRef("nullArray", "Kotlin"), false, 1));
+        add(pattern("iterator"), RETURN_RECEIVER_INTRINSIC);
     }
 }

js/js.translator/testFiles/expression/misc/cases/iterableExtension.kt

@@ -0,0 +1,22 @@
+package foo
+
+import java.util.*
+import java.lang.*
+import jet.Iterator
+
+public inline fun <T, C: Collection<in T>> Iterator<T>.takeWhileTo(result: C, predicate: (T) -> Boolean) : C {
+    for (element in this) if (predicate(element)) result.add(element) else break
+    return result
+}
+
+fun box(): Any? {
+    val c = ArrayList<Int>()
+    for (i in 0..5) {
+        c.add(i)
+    }
+
+    val d = ArrayList<Int>()
+
+    c.iterator().takeWhileTo(d, {i -> i < 4 })
+    return d.size() == 4
+}

js/js.translator/testFiles/expression/misc/cases/iterationOverIterator.kt

@@ -0,0 +1,18 @@
+package foo
+
+
+import java.util.*
+
+fun box(): Boolean {
+    val c = ArrayList<Int>()
+    for (i in 0..5) {
+        c.add(i)
+    }
+
+    var s = ""
+    for (i in c.iterator()) {
+        s = s + i.toString()
+    }
+
+    return s == "012345"
+}