[js] Implement box_s/unbox_s. Serializing a P6str.

src/vm/js/QAST/Compiler.nqp

@@ -1225,6 +1225,9 @@ class QAST::OperationsJS {
     add_simple_op('box_n', $T_OBJ, [$T_NUM, $T_OBJ]);
     add_simple_op('unbox_n', $T_NUM, [$T_OBJ]);
 
+    add_simple_op('box_s', $T_OBJ, [$T_STR, $T_OBJ]);
+    add_simple_op('unbox_s', $T_STR, [$T_OBJ]);
+
     add_simple_op('iseq_I', $T_INT, [$T_OBJ, $T_OBJ]);
 
     # bigint arithmetic operators operators

src/vm/js/nqp-runtime/core.js

@@ -427,3 +427,14 @@ op.box_n = function(n, type) {
 op.unbox_n = function(obj) {
     return obj.$$get_num();
 };
+
+op.box_s = function(value, type) {
+  var repr = type._STable.REPR;
+  var obj = repr.allocate(type._STable);
+  obj.$$set_str(value);
+  return obj;
+};
+
+op.unbox_s = function(obj) {
+    return obj.$$get_str();
+};

src/vm/js/nqp-runtime/reprs.js

@@ -415,7 +415,30 @@ module.exports.P6num = P6num;
 
 function P6str() {
 }
-P6str.prototype.create_obj_constructor = basic_constructor;
+
+P6str.prototype.allocate = basic_allocate;
+P6str.prototype.basic_constructor = basic_constructor;
+P6str.prototype.create_obj_constructor = function(STable) {
+  var c = this.basic_constructor(STable);
+
+  STable.obj_constructor = c; // HACK it's set again later, we set it for addInternalMethod
+
+  STable.addInternalMethod('$$set_str', function(value) {
+    this.value = value;
+  });
+  STable.addInternalMethod('$$get_str', function() {
+    return this.value;
+  });
+  return c;
+};
+
+P6str.prototype.serialize = function(data, object) {
+  data.str(object.value);
+};
+
+P6str.prototype.deserialize_finish = function(object, data) {
+  object.value = data.str();
+};
 
 P6str.name = 'P6str';
 module.exports.P6str = P6str;

src/vm/js/nqp-runtime/serialization.js

@@ -25,7 +25,7 @@ BinaryWriteCursor.prototype.growToHold = function(space) {
   }
 };
 
-BinaryWriteCursor.prototype.string = function(str) {
+BinaryWriteCursor.prototype.str = function(str) {
   if (str === undefined) {
     console.trace('undefined string');
     str = '?';
@@ -275,8 +275,8 @@ SerializationWriter.prototype.getSCId = function(sc) {
   /* Otherwise, need to add it to our dependencies list. */
   this.dependentSCs.push(sc);
 
-  this.deps.string(sc.handle);
-  this.deps.string(sc.description);
+  this.deps.str(sc.handle);
+  this.deps.str(sc.description);
 
   return this.dependentSCs.length; /* Deliberately index + 1. */
 };