[truffle] Implement nqp::chr

src/vm/jvm/Truffle.nqp

@@ -220,6 +220,8 @@ class QAST::OperationsTruffle {
 
     add_simple_op('x', $STR, [$STR, $INT]);
 
+    add_simple_op('chr', $STR, [$INT]);
+
     for <postinc postdec> -> $op {
         add_op($op, sub ($comp, $node, :$want) {
             my $old_value := $comp.as_truffle($node[0], :want($INT));

src/vm/jvm/runtime/org/perl6/nqp/truffle/nodes/expression/NQPChrNode.java

@@ -0,0 +1,26 @@
+package org.perl6.nqp.truffle.nodes.expression;
+import com.oracle.truffle.api.frame.VirtualFrame;
+import com.oracle.truffle.api.nodes.NodeInfo;
+import org.perl6.nqp.truffle.nodes.NQPNode;
+import org.perl6.nqp.truffle.nodes.NQPStrNode;
+import org.perl6.nqp.dsl.Deserializer;
+
+@NodeInfo(shortName = "chr")
+public final class NQPChrNode extends NQPStrNode {
+    @Child private NQPNode argNode;
+
+    @Deserializer
+    public NQPChrNode(NQPNode argNode) {
+        this.argNode = argNode;
+    }
+
+    @Override
+    public String executeStr(VirtualFrame frame) {
+        long ord = argNode.executeInt(frame);
+
+        if (ord < 0)
+            throw new RuntimeException("chr codepoint cannot be negative");
+
+        return (new StringBuffer()).append(Character.toChars((int)ord)).toString();
+    }
+}