Subset accesses always match string indexes exactly.

com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/InfixEmulationFunctions.java

@@ -217,11 +217,11 @@ public class InfixEmulationFunctions {
         protected final ConditionProfile multiIndexProfile = ConditionProfile.createBinaryProfile();
 
         protected Object getInternal(VirtualFrame frame, Object x, RArgsValuesAndNames inds, RAbstractLogicalVector dropVec) {
-            return access(frame, x, RRuntime.LOGICAL_FALSE, inds, dropVec, IS_SUBSET);
+            return access(frame, x, RRuntime.LOGICAL_TRUE, inds, dropVec, IS_SUBSET);
         }
 
         protected Object getInternal(VirtualFrame frame, Object x, RArgsValuesAndNames inds, RMissing dropVec) {
-            return access(frame, x, RRuntime.LOGICAL_FALSE, inds, dropVec, IS_SUBSET);
+            return access(frame, x, RRuntime.LOGICAL_TRUE, inds, dropVec, IS_SUBSET);
         }
 
         @SuppressWarnings("unused")

com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/library/base/TestSimpleVectors.java

@@ -269,6 +269,7 @@ public class TestSimpleVectors extends TestBase {
         assertEval("{ x<-c(TRUE,TRUE,FALSE); x[2L] }");
         assertEval("{ x<-c(TRUE,TRUE,FALSE); x[3L] }");
 
+        assertEval("{ v<-c(a=\"foo\", aa=\"me\"); v[\"a\"] }");
         assertEval("{ x<-c(1,2); x[c(\"a\")] }");
         assertEval(Output.ContainsError, "{ x<-c(1,2); x[[c(\"a\")]] }");
         assertEval("{ x<-c(1,2); dim(x)<-c(1,2); x[c(\"a\")] }");