Convert dualmode_insertcell.js

[sheshtawy]

This PR is addressing issue #3335 in order to convert js tests to selenium. It contains the conversion of the file notebook/tests/notebook/dualmode_insertcell.js

[takluyver]

👍 are you waiting for anything from us?

[sheshtawy]

No, I'm sorry I just got busy with a little task at work. I'll start working on notebook once I'm done with it I promise it will be soon). Thanks for checking in :)

[sheshtawy]

@takluyver I have a question
For the code block below (it's from from dualmode_cellinsert.js) I don't understand why it exists, it kinda feels repetitive. Can you help me understand why do we have it?

this.then(function () {
        this.select_cell(2);
        this.trigger_keydown('y'); // switch it to code for the next test
        this.test.assertEquals(this.get_cell(2).cell_type, 'code', 'test cell is code');
        this.trigger_keydown('b'); // new cell below
        this.test.assertEquals(this.get_cell(3).cell_type, 'code', 'b; inserts a code cell below code cell');
        this.trigger_keydown('a'); // new cell above
        this.test.assertEquals(this.get_cell(3).cell_type, 'code', 'a; inserts a code cell above code cell');
    });
    
    this.then(function () {
        this.set_cell_text(1, 'cell1');
        this.select_cell(1);
        this.select_cell(2, false);
        this.trigger_keydown('a');
        this.test.assertEquals(this.get_cell_text(1), '', 'a; New cell 1 text is empty');
        this.test.assertEquals(this.get_cell_text(2), 'cell1', 'a; Cell 2 text is old cell 1');
        
        this.set_cell_text(1, 'cell1');
        this.set_cell_text(2, 'cell2');
        this.set_cell_text(3, 'cell3');
        this.select_cell(1);
        this.select_cell(2, false);
        this.trigger_keydown('b');
        this.test.assertEquals(this.get_cell_text(1), 'cell1', 'b; Cell 1 remains');
        this.test.assertEquals(this.get_cell_text(2), 'cell2', 'b; Cell 2 remains');
        this.test.assertEquals(this.get_cell_text(3), '', 'b; Cell 3 is new');
        this.test.assertEquals(this.get_cell_text(4), 'cell3', 'b; Cell 4 text is old cell 3');
    });

[takluyver]

The first chunk is a simple test for inserting a cell above and below the current one, though it doesn't look like it's a very good test.

The second part is testing with multiple cells selected, to check that the new cell is added in the right place - before the first selected cell, or after the last selected cell.

[sheshtawy]

So just to make sure I understand the purpose of the test correctly and not just copy it from js to python:

• The main purpose of this test case is to test the "insert" functionality in both edit and command modes? Or is it just about testing out insertion in different scenarios? @takluyver

[takluyver]

I think it's only dealing with command mode. IIRC, all the dualmode_*.js test files were added when we introduced the distinction between edit mode and command mode, to test the behaviour and the new shortcuts.

[takluyver]

I think the thing this is trying to test no longer works like that. We used to insert a new cell of the same type as the one you had selected, but we eventually decided it was easier to follow if it was always a code cell that was inserted. The test passes, but I think that's two accidents cancelling each other out - the cell you converted to markdown becomes number 3, then number 4, as you insert other cells.

[sheshtawy]

Oh .. okay. I will remove those steps and assertions then. Do you have any other comments?

[sheshtawy]

I was actually confused about that. I tried to do the test manually and I wasn't able to insert markdown cells. It all makes sense now

[sheshtawy]

Also, I deeply apologize for the delay in submitting this PR. I will do my best to make sure this doesn't happen again and I hope this doesn't affect your idea of how committed I am to the team and the project.

[takluyver]

No need to apologise! Everyone gets busy at times, and no-one expects volunteer contributors to do things by any set deadline. We might ping you on unfinished pull requests in case you've forgotten about it, or in case you're waiting for us to answer something, but if you don't have time to work on it, that's fine. If it's urgent, someone else can pick it up and finish it, and if not, it can wait. :-)

[takluyver]

I'm a bit too tired for a detailed review now, but I think it's still missing the tests from the JS version which check inserting a cell when multiple cells are already selected?

Once you're happy that you've made Python equivalents of the JS tests, feel free to go ahead and delete the JS file in this PR.

[takluyver]

For something like this, I think it would be an improvement to get all the cells at once:

assert notebook.get_cells_contents()[:4] == ["", "cell1", "cell2", ""]

If the test fails, I think the comparison of the lists will give a more informative error to see what has gone wrong. It's also shorter and I guess it's more efficient (less requests to the browser).

[takluyver]

Thanks!