fix broken selection when the first column is invisible

[azmy60]

When starting tabulator with SelectRange enabled, the selection is not on the top left. This is because we have a table that the first column is invisible and that column get processed, which shouldn't.

Demo: https://jsfiddle.net/zqd0kgwr/

[olifolkerd]

Hey @azmy60

Thanks for the fix, i will include it in the 6.0 release.

Just a quick note on your variable definitions, as I've had to tidy these up on some of your past commits. It is considered bad practice to declare a variable anywhere other than at the top of the function if using a var (let can be defined at top of logical block). When you define them later in the function you are making more work for the interpreter as it has to hoist them to the top of the function anyway before it can execute the code.

You should define all variables used in a function at the top of the function, then assign them later if needed.

To be clear, this is how your PR has your code structured:

resetRanges() {
    ....
    if(this.table.rowManager.activeRows.length){
        var visibleCells = this.table.rowManager.activeRows[0].cells.filter((cell) => cell.column.visible);
        cell = visibleCells[this.rowHeader ? 1 : 0];
    }
}

It should be:

resetRanges() {
    var visibleCells;
    ....
    if(this.table.rowManager.activeRows.length){
        visibleCells = this.table.rowManager.activeRows[0].cells.filter((cell) => cell.column.visible);
        cell = visibleCells[this.rowHeader ? 1 : 0];
    }
}

Not only does this reduce the work on the JS interpreter (it has to do this hoisting anyway before it can execute the code), it makes it clear to other developers what variables are available inside the function call.

Cheers

Oli :)

[azmy60]

Ah, I see why that needs to be on top. Thanks!