Method defineOwnProperty

src/main/java/org/dynjs/runtime/DynArray.java:30–111

(ExecutionContext context, String name, PropertyDescriptor desc, boolean shouldThrow)

    }

    @Override
    public boolean defineOwnProperty(ExecutionContext context, String name, PropertyDescriptor desc, boolean shouldThrow) {
        // 15.4.5.1
        PropertyDescriptor oldLenDesc = (PropertyDescriptor) getOwnProperty(context, "length");
        long oldLen = (long) oldLenDesc.getValue();

        if (name.equals("length")) {
            if (desc.getValue() == null ) {
                return super.defineOwnProperty(context, "length", desc, shouldThrow);
            }

            PropertyDescriptor newLenDesc = desc;
            Long newLen = Types.toUint32(context, desc.getValue());
            if (!Types.compareEquality(context, newLen, Types.toNumber(context, desc.getValue()))) {
                throw new ThrowException(context, context.createRangeError("invalid length: " + newLen));
            }
            newLenDesc.setValue(newLen);
            if (newLen >= oldLen) {
                return super.defineOwnProperty(context, "length", newLenDesc, shouldThrow);
            }

            if (!oldLenDesc.hasWritable() && !oldLenDesc.isWritable()) {
                return reject(context, shouldThrow);
            }

            boolean newWritable = false;
            if ((!newLenDesc.hasWritable()) || newLenDesc.isWritable()) {
                newWritable = true;
            } else {
                newWritable = false;
                newLenDesc.setWritable(true);
            }

            boolean succeeded = super.defineOwnProperty(context, "length", newLenDesc, shouldThrow);

            if (!succeeded) {
                return false;
            }

            while (newLen < oldLen) {
                oldLen = oldLen - 1;
                boolean deleteSucceeded = delete(context, "" + oldLen, false);

                if (!deleteSucceeded) {
                    newLenDesc.setValue(oldLen + 1);
                    if (!newWritable) {
                        newLenDesc.setWritable(false);
                    }
                    super.defineOwnProperty(context, "length", newLenDesc, false);
                    return reject(context, shouldThrow);

                }
            }

            if (newWritable == false) {
                PropertyDescriptor lengthDesc = new PropertyDescriptor();
                lengthDesc.setWritable(false);
                super.defineOwnProperty(context, "length", lengthDesc, false);