text: /**
   * Tests for the interaction between FTS indexes and arrays.
   */
  (function() {
  "use strict";
  
  let coll = db.jstests_fts_array;
  coll.drop();
  assert.commandWorked(coll.createIndex({"a.b": 1, words: "text"}));
  
  // Verify that the leading field of the index cannot contain an array.
  assert.writeErrorWithCode(coll.insert({a: {b: []}, words: "omnibus"}),
                            ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({a: {b: [1]}, words: "omnibus"}),
                            ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({a: {b: [1, 2]}, words: "omnibus"}),
                            ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({a: [], words: "omnibus"}), ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({a: [{b: 1}], words: "omnibus"}),
                            ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({a: [{b: 1}, {b: 2}], words: "omnibus"}),
                            ErrorCodes.CannotBuildIndexKeys);
  
  coll.drop();
  assert.commandWorked(coll.createIndex({words: "text", "y.z": 1}));
  
  // Verify that the trailing field of the index cannot contain an array.
  assert.writeErrorWithCode(coll.insert({words: "macerate", y: {z: []}}),
                            ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({words: "macerate", y: {z: [1]}}),
                            ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({words: "macerate", y: {z: [1, 2]}}),
                            ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({words: "macerate", y: []}), ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({words: "macerate", y: [{z: 1}]}),
                            ErrorCodes.CannotBuildIndexKeys);
  assert.writeErrorWithCode(coll.insert({words: "macerate", y: [{z: 1}, {z: 2}]}),
                            ErrorCodes.CannotBuildIndexKeys);
  
  // Verify that array fields are allowed when positionally indexed.
  coll.drop();
  assert.commandWorked(coll.createIndex({"a.0": 1, words: "text"}));
  assert.commandWorked(coll.insert({a: [0, 1, 2], words: "dander"}));
  assert.eq({a: [0, 1, 2], words: "dander"},
            coll.findOne({"a.0": 0, $text: {$search: "dander"}}, {_id: 0, a: 1, words: 1}));
  assert.writeErrorWithCode(coll.insert({a: [[8, 9], 1, 2], words: "dander"}),
                            ErrorCodes.CannotBuildIndexKeys);
  coll.drop();
  assert.commandWorked(coll.createIndex({"a.0.1": 1, words: "text"}));
  assert.commandWorked(coll.insert({a: [[8, 9], 1, 2], words: "dander"}));
  assert.eq({a: [[8, 9], 1, 2], words: "dander"},
            coll.findOne({"a.0.1": 9, $text: {$search: "dander"}}, {_id: 0, a: 1, words: 1}));
  }());
  