text: /*
   * SERVER-6147 : aggregation $ne expression applied to constant returns incorrect result
   *
   * This test validates the SERVER-6147 ticket. Return true when comparing a constant to a field
   * containing a different value using $ne. Previously it would return false when comparing a
   * constant and a field regardless of whether they were equal or not.
   */
  
  /*
   * 1) Clear and create testing db
   * 2) Run an aggregation with $ne comparing constants and fields in various configurations
   * 3) Assert that the result is what we expected
   */
  
  // Clear db
  db.s6147.drop();
  
  // Populate db
  db.s6147.save({a:1});
  db.s6147.save({a:2});
  
  // Aggregate checking various combinations of the constant and the field
  var s6147 = db.runCommand(
  { aggregate: "s6147", pipeline : [
      { $project : {
          _id : 0,
          constantAndField : { $ne: [1, "$a"] },
          fieldAndConstant : { $ne: ["$a", 1] },
          constantAndConstant : { $ne: [1, 1] },
          fieldAndField : { $ne: ["$a", "$a"] }
      }}
  ]});
  
  /*
   * In both documents the constantAndConstant and fieldAndField should be false since they compare
   * something with itself but the constantAndField and fieldAndConstant should be different as
   * document one contains 1 which should return false and document 2 contains something different so
   * should return true
   */
  var s6147result = [
      {
          constantAndField : false,
          fieldAndConstant : false,
          constantAndConstant : false,
          fieldAndField : false
      },
      {
          constantAndField : true,
          fieldAndConstant : true,
          constantAndConstant : false,
          fieldAndField : false
      }
  ];
  
  // Assert
  assert.eq(s6147.result, s6147result, 's6147 failed');
  