Silent Failure of a Controller Update Action Test in RSpec

# The Failing Test:
RSpec.describe PiecesController, type: :controller do
  describe "Action: pieces#update" do
    it "should create a move when a move is valid" do
      user = FactoryGirl.create(:user)
      sign_in user
      game = FactoryGirl.create(:game, :white_player_id => user.id)
      # Test a white pawn's movement on its first turn:
      piece = FactoryGirl.create(:piece, :game => game, :player_id => user.id)
      move = FactoryGirl.create(:move, :piece => piece)
      if piece.valid_move?({ :x_position => piece.x_position, :y_position => 5, :type => piece.type, :captured => piece.captured })
        # Move the pawn 2 vertical spaces on its first turn, and record the move:
        # *** PROBLEM: The piece's y-position is not being updated. ***
        patch :update, :id => piece.id, :piece => { :y_position => 5 }, :format => :js
        piece.reload
       # *** The expectation below fails. ***
        expect(piece.y_position).to eq 5
      else
        # Safety condition to ensure the test fails visibly when the move is invalid.
        expect(move.move_count).to eq "Invalid move!"
      end
    end
  end
end

# Associations:
class User < ActiveRecord::Base
  ...
  has_and_belongs_to_many :games
  has_many :pieces, foreign_key: :player_id
  ...
end

class Game < ActiveRecord::Base
  has_many :pieces
  has_many :moves, through: :pieces
  belongs_to :white_player, class_name: 'User', foreign_key: :white_player_id
  belongs_to :black_player, class_name: 'User', foreign_key: :black_player_id
  ...
end

class Piece < ActiveRecord::Base
  belongs_to :game
  has_many :moves

  def valid_move?(params)
    ...
  end
  ...
end

# Factories:
FactoryGirl.define do

  factory :user do
    ...
  end

  factory :game do
    association :white_player, factory: :user
    association :black_player, factory: :user
    turn 1
  end

  factory :piece do
    association :game
    type "Pawn"
    color "white"
    captured false
    x_position 1
    y_position 7
  end

  factory :move do
    association :piece
    ...
  end

end

# Pieces Controller:
class PiecesController < ApplicationController
  before_action :authenticate_user!
  before_action :require_authorized_for_current_game, only: [:update]
  before_action :require_authorized_for_current_piece, only: [:update]
  before_action :valid?, only: [:update]

  def update
    current_piece.capture_piece(piece_params)
    Piece.find_by_id(params[:id]).update_attributes(piece_params) # Do not use current_piece here solely for pawn promotion
    current_game.next_turn
    # Send a message back to the JS after the update (after the data object is defined in the AJAX request) to confirm successful update or an error:
    respond_to do |format|
      format.js { render json: {success: true, status: :success} }
    end
  end

  private

  def current_piece
    @current_piece ||= Piece.find_by_id(params[:id])
  end

  def require_authorized_for_current_piece
    if current_piece.player_id != current_user.id
      render text: 'Unauthorized', status: :unauthorized
    end
  end

  def piece_params
    params.require(:piece).permit(:x_position, :y_position, :type, :captured)
  end

  def current_game
    @current_game ||= current_piece.game
  end

  def require_authorized_for_current_game
    if current_game.white_player != current_user && current_game.black_player != current_user
      render text: 'Unauthorized', status: :unauthorized
    end
  end

  def valid?
    if !current_game.your_turn?(current_piece) || !current_piece.valid_move?(piece_params)
      render text: 'Unauthorized', status: :unauthorized
    end
  end
end