unwrap parentheses around range expressions in pattern matching conditions (KT-1742) (thanks to Sergey Mashkov for the suggested fix)

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

@@ -2868,6 +2868,9 @@ If finally block is present, its last expression is the value of try expression.
         if (condition instanceof JetWhenConditionInRange) {
             JetWhenConditionInRange conditionInRange = (JetWhenConditionInRange) condition;
             JetExpression rangeExpression = conditionInRange.getRangeExpression();
+            while (rangeExpression instanceof JetParenthesizedExpression) {
+                rangeExpression = ((JetParenthesizedExpression)rangeExpression).getExpression();
+            }
             if(isIntRangeExpr(rangeExpression)) {
                 getInIntRange(new StackValue.Local(subjectLocal, subjectType), (JetBinaryExpression) rangeExpression, conditionInRange.getOperationReference().getReferencedNameElementType() == JetTokens.NOT_IN);
             }

compiler/testData/codegen/regressions/kt1742.kt

@@ -0,0 +1,7 @@
+fun box(): String {
+    val x = 2
+    return when(x) {
+        in (1..3) -> "OK"
+        else -> "fail"
+    }
+}

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

@@ -341,4 +341,9 @@ public class ControlStructuresTest extends CodegenTestCase {
         createEnvironmentWithMockJdkAndIdeaAnnotations(CompilerSpecialMode.JDK_HEADERS);
         blackBoxFile("regressions/kt1899.kt");
     }
+
+    public void testKt1742() throws Exception {
+        createEnvironmentWithMockJdkAndIdeaAnnotations(CompilerSpecialMode.JDK_HEADERS);
+        blackBoxFile("regressions/kt1742.kt");
+    }
 }