dataview.js

(function ($) {

  module("basic");

  function assertEmpty(dv) {
    same(0, dv.getLength(), ".rows is initialized to an empty array");
    same(dv.getItems().length, 0, "getItems().length");
    same(undefined, dv.getIdxById("id"), "getIdxById should return undefined if not found");
    same(undefined, dv.getRowById("id"), "getRowById should return undefined if not found");
    same(undefined, dv.getItemById("id"), "getItemById should return undefined if not found");
    same(undefined, dv.getItemByIdx(0), "getItemByIdx should return undefined if not found");
  }

  function assertConsistency(dv, idProperty) {
    idProperty = idProperty || "id";
    var items = dv.getItems(),
      filteredOut = 0,
      row,
      id;

    for (var i = 0; i < items.length; i++) {
      id = items[i][idProperty];
      same(dv.getItemByIdx(i), items[i], "getItemByIdx");
      same(dv.getItemById(id), items[i], "getItemById");
      same(dv.getIdxById(id), i, "getIdxById");

      row = dv.getRowById(id);
      if (row === undefined)
        filteredOut++;
      else
        same(dv.getItem(row), items[i], "getRowById");
    }

    same(items.length - dv.getLength(), filteredOut, "filtered rows");
  }

  test("initial setup", function () {
    var dv = new Slick.Data.DataView();
    assertEmpty(dv);
  });

  test("initial setup, refresh", function () {
    var dv = new Slick.Data.DataView();
    dv.refresh();
    assertEmpty(dv);
  });


  module("setItems");

  test("empty", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([]);
    assertEmpty(dv);
  });

  test("basic", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0},
      {id: 1}
    ]);
    same(2, dv.getLength(), "rows.length");
    same(dv.getItems().length, 2, "getItems().length");
    assertConsistency(dv);
  });

  test("alternative idProperty", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {uid: 0},
      {uid: 1}
    ], "uid");
    assertConsistency(dv, "uid");
  });

  test("requires an id on objects", function () {
    var dv = new Slick.Data.DataView();
    try {
      dv.setItems([1, 2, 3]);
      ok(false, "exception expected");
    }
    catch (ex) {
    }
  });

  test("requires a unique id on objects", function () {
    var dv = new Slick.Data.DataView();
    try {
      dv.setItems([
        {id: 0},
        {id: 0}
      ]);
      ok(false, "exception expected");
    }
    catch (ex) {
    }
  });

  test("requires a unique id on objects (alternative idProperty)", function () {
    var dv = new Slick.Data.DataView();
    try {
      dv.setItems([
        {uid: 0},
        {uid: 0}
      ], "uid");
      ok(false, "exception expected");
    }
    catch (ex) {
    }
  });

  test("events fired on setItems", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      same(args.previous, 0, "previous arg");
      same(args.current, 2, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      same(args.pageSize, 0, "pageSize arg");
      same(args.pageNum, 0, "pageNum arg");
      same(args.totalRows, 2, "totalRows arg");
      count++;
    });
    dv.setItems([
      {id: 0},
      {id: 1}
    ]);
    dv.refresh();
    same(3, count, "3 events should have been called");
  });

  test("no events on setItems([])", function () {
    var dv = new Slick.Data.DataView();
    dv.onRowsChanged.subscribe(function () {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function () {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function () {
      ok(false, "onPagingInfoChanged called");
    });
    dv.setItems([]);
    dv.refresh();
  });

  test("no events on setItems followed by refresh", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0},
      {id: 1}
    ]);
    dv.onRowsChanged.subscribe(function () {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function () {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function () {
      ok(false, "onPagingInfoChanged called");
    });
    dv.refresh();
  });

  test("no refresh while suspended", function () {
    var dv = new Slick.Data.DataView();
    dv.beginUpdate();
    dv.onRowsChanged.subscribe(function () {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function () {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function () {
      ok(false, "onPagingInfoChanged called");
    });
    dv.setItems([
      {id: 0},
      {id: 1}
    ]);
    dv.setFilter(function (o) {
      return true;
    });
    dv.refresh();
    same(dv.getLength(), 0, "rows aren't updated until resumed");
  });

  test("refresh fires after resume", function () {
    var dv = new Slick.Data.DataView();
    dv.beginUpdate();
    dv.setItems([
      {id: 0},
      {id: 1}
    ]);
    same(dv.getItems().length, 2, "items updated immediately");
    dv.setFilter(function (o) {
      return true;
    });
    dv.refresh();

    var count = 0;
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [0, 1]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      same(args.previous, 0, "previous arg");
      same(args.current, 2, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      same(args.pageSize, 0, "pageSize arg");
      same(args.pageNum, 0, "pageNum arg");
      same(args.totalRows, 2, "totalRows arg");
      count++;
    });
    dv.endUpdate();
    equal(count, 3, "events fired");
    same(dv.getItems().length, 2, "items are the same");
    same(dv.getLength(), 2, "rows updated");
  });

  module("sort");

  test("happy path", function () {
    var count = 0;
    var items = [
      {id: 2, val: 2},
      {id: 1, val: 1},
      {id: 0, val: 0}
    ];
    var dv = new Slick.Data.DataView();
    dv.setItems(items);
    dv.onRowsChanged.subscribe(function () {
      ok(true, "onRowsChanged called");
      count++;
    });
    dv.onRowCountChanged.subscribe(function () {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function () {
      ok(false, "onPagingInfoChanged called");
    });
    dv.sort(function (x, y) {
      return x.val - y.val
    }, true);
    equal(count, 1, "events fired");
    same(dv.getItems(), items, "original array should get sorted");
    same(items, [
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ], "sort order");
    assertConsistency(dv);
  });

  test("asc by default", function () {
    var items = [
      {id: 2, val: 2},
      {id: 1, val: 1},
      {id: 0, val: 0}
    ];
    var dv = new Slick.Data.DataView();
    dv.setItems(items);
    dv.sort(function (x, y) {
      return x.val - y.val
    });
    same(items, [
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ], "sort order");
  });

  test("desc", function () {
    var items = [
      {id: 0, val: 0},
      {id: 2, val: 2},
      {id: 1, val: 1}
    ];
    var dv = new Slick.Data.DataView();
    dv.setItems(items);
    dv.sort(function (x, y) {
      return -1 * (x.val - y.val)
    });
    same(items, [
      {id: 2, val: 2},
      {id: 1, val: 1},
      {id: 0, val: 0}
    ], "sort order");
  });

  test("sort is stable", function () {
    var items = [
      {id: 0, val: 0},
      {id: 2, val: 2},
      {id: 3, val: 2},
      {id: 1, val: 1}
    ];
    var dv = new Slick.Data.DataView();
    dv.setItems(items);

    dv.sort(function (x, y) {
      return x.val - y.val;
    });
    same(items, [
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2},
      {id: 3, val: 2}
    ], "sort order");

    dv.sort(function (x, y) {
      return x.val - y.val
    });
    same(items, [
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2},
      {id: 3, val: 2}
    ], "sorting on the same column again doesn't change the order");

    dv.sort(function (x, y) {
      return -1 * (x.val - y.val);
    });
    same(items, [
      {id: 2, val: 2},
      {id: 3, val: 2},
      {id: 1, val: 1},
      {id: 0, val: 0}
    ], "sort order");
  });


  module("filtering");

  test("applied immediately", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [0]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      same(args.previous, 3, "previous arg");
      same(args.current, 1, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      same(args.pageSize, 0, "pageSize arg");
      same(args.pageNum, 0, "pageNum arg");
      same(args.totalRows, 1, "totalRows arg");
      count++;
    });
    dv.setFilter(function (o) {
      return o.val === 1;
    });
    equal(count, 3, "events fired");
    same(dv.getItems().length, 3, "original data is still there");
    same(dv.getLength(), 1, "rows are filtered");
    assertConsistency(dv);
  });

  test("re-applied on refresh", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.setFilterArgs(0);
    dv.setFilter(function (o, args) {
      return o.val >= args;
    });
    same(dv.getLength(), 3, "nothing is filtered out");
    assertConsistency(dv);

    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [0]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      same(args.previous, 3, "previous arg");
      same(args.current, 1, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      same(args.pageSize, 0, "pageSize arg");
      same(args.pageNum, 0, "pageNum arg");
      same(args.totalRows, 1, "totalRows arg");
      count++;
    });
    dv.setFilterArgs(2);
    dv.refresh();
    equal(count, 3, "events fired");
    same(dv.getItems().length, 3, "original data is still there");
    same(dv.getLength(), 1, "rows are filtered");
    assertConsistency(dv);
  });

  test("re-applied on sort", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.setFilter(function (o) {
      return o.val === 1;
    });
    same(dv.getLength(), 1, "one row is remaining");

    dv.onRowsChanged.subscribe(function () {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function () {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function () {
      ok(false, "onPagingInfoChanged called");
    });
    dv.sort(function (x, y) {
      return x.val - y.val;
    }, false);
    same(dv.getItems().length, 3, "original data is still there");
    same(dv.getLength(), 1, "rows are filtered");
    assertConsistency(dv);
  });

  test("all", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      same(args.previous, 3, "previous arg");
      same(args.current, 0, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      same(args.pageSize, 0, "pageSize arg");
      same(args.pageNum, 0, "pageNum arg");
      same(args.totalRows, 0, "totalRows arg");
      count++;
    });
    dv.setFilter(function (o) {
      return false;
    });
    equal(count, 2, "events fired");
    same(dv.getItems().length, 3, "original data is still there");
    same(dv.getLength(), 0, "rows are filtered");
    assertConsistency(dv);
  });

  test("all then none", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.setFilterArgs(false);
    dv.setFilter(function (o, args) {
      return args;
    });
    same(dv.getLength(), 0, "all rows are filtered out");

    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [0, 1, 2]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      same(args.previous, 0, "previous arg");
      same(args.current, 3, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      same(args.pageSize, 0, "pageSize arg");
      same(args.pageNum, 0, "pageNum arg");
      same(args.totalRows, 3, "totalRows arg");
      count++;
    });
    dv.setFilterArgs(true);
    dv.refresh();
    equal(count, 3, "events fired");
    same(dv.getItems().length, 3, "original data is still there");
    same(dv.getLength(), 3, "all rows are back");
    assertConsistency(dv);
  });

  test("inlining replaces absolute returns", function () {
    var dv = new Slick.Data.DataView({ inlineFilters: true });
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.setFilter(function (o) {
      if (o.val === 1) {
        return true;
      }
      else if (o.val === 4) {
        return true;
      }
      return false;
    });
    same(dv.getLength(), 1, "one row is remaining");

    dv.onRowsChanged.subscribe(function () {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function () {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function () {
      ok(false, "onPagingInfoChanged called");
    });
    same(dv.getItems().length, 3, "original data is still there");
    same(dv.getLength(), 1, "rows are filtered");
    assertConsistency(dv);
  });

  test("inlining replaces evaluated returns", function () {
    var dv = new Slick.Data.DataView({ inlineFilters: true });
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.setFilter(function (o) {
      if (o.val === 0) {
        return o.id === 2;
      }
      else if (o.val === 1) {
        return o.id === 2;
      }
      return o.val === 2;
    });
    same(dv.getLength(), 1, "one row is remaining");

    dv.onRowsChanged.subscribe(function () {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function () {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function () {
      ok(false, "onPagingInfoChanged called");
    });
    same(dv.getItems().length, 3, "original data is still there");
    same(dv.getLength(), 1, "rows are filtered");
    assertConsistency(dv);
  });

  module("updateItem");

  test("basic", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);

    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [1]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(false, "onPagingInfoChanged called");
    });

    dv.updateItem(1, {id: 1, val: 1337});
    equal(count, 1, "events fired");
    same(dv.getItem(1), {id: 1, val: 1337}, "item updated");
    assertConsistency(dv);
  });

  test("updating an item not passing the filter", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2},
      {id: 3, val: 1337}
    ]);
    dv.setFilter(function (o) {
      return o["val"] !== 1337;
    });
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(false, "onPagingInfoChanged called");
    });
    dv.updateItem(3, {id: 3, val: 1337});
    same(dv.getItems()[3], {id: 3, val: 1337}, "item updated");
    assertConsistency(dv);
  });

  test("updating an item to pass the filter", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2},
      {id: 3, val: 1337}
    ]);
    dv.setFilter(function (o) {
      return o["val"] !== 1337;
    });
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [3]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      equal(args.previous, 3, "previous arg");
      equal(args.current, 4, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      same(args.pageSize, 0, "pageSize arg");
      same(args.pageNum, 0, "pageNum arg");
      same(args.totalRows, 4, "totalRows arg");
      count++;
    });
    dv.updateItem(3, {id: 3, val: 3});
    equal(count, 3, "events fired");
    same(dv.getItems()[3], {id: 3, val: 3}, "item updated");
    assertConsistency(dv);
  });

  test("updating an item to not pass the filter", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2},
      {id: 3, val: 3}
    ]);
    dv.setFilter(function (o) {
      return o["val"] !== 1337;
    });
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      equal(args.previous, 4, "previous arg");
      equal(args.current, 3, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      same(args.pageSize, 0, "pageSize arg");
      same(args.pageNum, 0, "pageNum arg");
      same(args.totalRows, 3, "totalRows arg");
      count++;
    });
    dv.updateItem(3, {id: 3, val: 1337});
    equal(count, 2, "events fired");
    same(dv.getItems()[3], {id: 3, val: 1337}, "item updated");
    assertConsistency(dv);
  });


  module("addItem");

  test("must have id", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    try {
      dv.addItem({val: 1337});
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
  });

  test("must have id (custom)", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {uid: 0, val: 0},
      {uid: 1, val: 1},
      {uid: 2, val: 2}
    ], "uid");
    try {
      dv.addItem({id: 3, val: 1337});
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
  });

  test("basic", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [3]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      equal(args.previous, 3, "previous arg");
      equal(args.current, 4, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      equal(args.pageSize, 0, "pageSize arg");
      equal(args.pageNum, 0, "pageNum arg");
      equal(args.totalRows, 4, "totalRows arg");
      count++;
    });
    dv.addItem({id: 3, val: 1337});
    equal(count, 3, "events fired");
    same(dv.getItems()[3], {id: 3, val: 1337}, "item updated");
    same(dv.getItem(3), {id: 3, val: 1337}, "item updated");
    assertConsistency(dv);
  });

  test("add an item not passing the filter", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.setFilter(function (o) {
      return o["val"] !== 1337;
    });
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(false, "onRowCountChanged called");
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(false, "onPagingInfoChanged called");
    });
    dv.addItem({id: 3, val: 1337});
    same(dv.getItems()[3], {id: 3, val: 1337}, "item updated");
    assertConsistency(dv);
  });

  module("insertItem");

  test("must have id", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    try {
      dv.insertItem(0, {val: 1337});
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
  });

  test("must have id (custom)", function () {
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {uid: 0, val: 0},
      {uid: 1, val: 1},
      {uid: 2, val: 2}
    ], "uid");
    try {
      dv.insertItem(0, {id: 3, val: 1337});
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
  });

  test("insert at the beginning", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [0, 1, 2, 3]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      equal(args.previous, 3, "previous arg");
      equal(args.current, 4, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      equal(args.pageSize, 0, "pageSize arg");
      equal(args.pageNum, 0, "pageNum arg");
      equal(args.totalRows, 4, "totalRows arg");
      count++;
    });
    dv.insertItem(0, {id: 3, val: 1337});
    equal(count, 3, "events fired");
    same(dv.getItem(0), {id: 3, val: 1337}, "item updated");
    equal(dv.getItems().length, 4, "items updated");
    equal(dv.getLength(), 4, "rows updated");
    assertConsistency(dv);
  });

  test("insert in the middle", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [2, 3]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      equal(args.previous, 3, "previous arg");
      equal(args.current, 4, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      equal(args.pageSize, 0, "pageSize arg");
      equal(args.pageNum, 0, "pageNum arg");
      equal(args.totalRows, 4, "totalRows arg");
      count++;
    });
    dv.insertItem(2, {id: 3, val: 1337});
    equal(count, 3, "events fired");
    same(dv.getItem(2), {id: 3, val: 1337}, "item updated");
    equal(dv.getItems().length, 4, "items updated");
    equal(dv.getLength(), 4, "rows updated");
    assertConsistency(dv);
  });

  test("insert at the end", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [3]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      equal(args.previous, 3, "previous arg");
      equal(args.current, 4, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      equal(args.pageSize, 0, "pageSize arg");
      equal(args.pageNum, 0, "pageNum arg");
      equal(args.totalRows, 4, "totalRows arg");
      count++;
    });
    dv.insertItem(3, {id: 3, val: 1337});
    equal(count, 3, "events fired");
    same(dv.getItem(3), {id: 3, val: 1337}, "item updated");
    equal(dv.getItems().length, 4, "items updated");
    equal(dv.getLength(), 4, "rows updated");
    assertConsistency(dv);
  });

  module("deleteItem");

  test("must have id", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 0, val: 0},
      {id: 1, val: 1},
      {id: 2, val: 2}
    ]);
    try {
      dv.deleteItem(-1);
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
    try {
      dv.deleteItem(undefined);
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
    try {
      dv.deleteItem(null);
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
    try {
      dv.deleteItem(3);
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
  });

  test("must have id (custom)", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {uid: 0, id: -1, val: 0},
      {uid: 1, id: 3, val: 1},
      {uid: 2, id: null, val: 2}
    ], "uid");
    try {
      dv.deleteItem(-1);
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
    try {
      dv.deleteItem(undefined);
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
    try {
      dv.deleteItem(null);
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
    try {
      dv.deleteItem(3);
      ok(false, "exception thrown");
    }
    catch (ex) {
    }
  });

  test("delete at the beginning", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 05, val: 0},
      {id: 15, val: 1},
      {id: 25, val: 2}
    ]);
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [0, 1]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      equal(args.previous, 3, "previous arg");
      equal(args.current, 2, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      equal(args.pageSize, 0, "pageSize arg");
      equal(args.pageNum, 0, "pageNum arg");
      equal(args.totalRows, 2, "totalRows arg");
      count++;
    });
    dv.deleteItem(05);
    equal(count, 3, "events fired");
    equal(dv.getItems().length, 2, "items updated");
    equal(dv.getLength(), 2, "rows updated");
    assertConsistency(dv);
  });

  test("delete in the middle", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 05, val: 0},
      {id: 15, val: 1},
      {id: 25, val: 2}
    ]);
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(true, "onRowsChanged called");
      same(args, {rows: [1]}, "args");
      count++;
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      equal(args.previous, 3, "previous arg");
      equal(args.current, 2, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      equal(args.pageSize, 0, "pageSize arg");
      equal(args.pageNum, 0, "pageNum arg");
      equal(args.totalRows, 2, "totalRows arg");
      count++;
    });
    dv.deleteItem(15);
    equal(count, 3, "events fired");
    equal(dv.getItems().length, 2, "items updated");
    equal(dv.getLength(), 2, "rows updated");
    assertConsistency(dv);
  });

  test("delete at the end", function () {
    var count = 0;
    var dv = new Slick.Data.DataView();
    dv.setItems([
      {id: 05, val: 0},
      {id: 15, val: 1},
      {id: 25, val: 2}
    ]);
    dv.onRowsChanged.subscribe(function (e, args) {
      ok(false, "onRowsChanged called");
    });
    dv.onRowCountChanged.subscribe(function (e, args) {
      ok(true, "onRowCountChanged called");
      equal(args.previous, 3, "previous arg");
      equal(args.current, 2, "current arg");
      count++;
    });
    dv.onPagingInfoChanged.subscribe(function (e, args) {
      ok(true, "onPagingInfoChanged called");
      equal(args.pageSize, 0, "pageSize arg");
      equal(args.pageNum, 0, "pageNum arg");
      equal(args.totalRows, 2, "totalRows arg");
      count++;
    });
    dv.deleteItem(25);
    equal(count, 2, "events fired");
    equal(dv.getItems().length, 2, "items updated");
    equal(dv.getLength(), 2, "rows updated");
    assertConsistency(dv);
  });

// TODO: paging
// TODO: combination


})(jQuery);