Just like the cursor clears its goal column when it is moved in any
way other than vertically, the selection clears its goal range (the
range it will attempt to use when adding a selection below) when it
is changed in any way.
Just like the cursor tries to stay in its "goal column" when moving
vertically, here we try to keep the same selection even when adding
across shorter lines.
Previously EditSession.backspaceToBeginningOfLine() would do nothing
if at the beginning of the line.
Now it selects left and does a delete so it can be used to delete
multiple lines continuously without having to move the cursor.
Refs #134
Normally, we don't autoscroll to a cursor when the buffer changes. But
this is a change caused by the cursor itself, so it makes sense to
keep it in view.
- EditSessions destroy their Selections when they are destroyed
- Editors destroy their EditSessions when they are destroyed
- Editors unsubscribe from the document and window when they are
removed from the DOM.
- When an EditSession is destroyed via any code path, the Editor with
that EditSession removes it.
- Selections no longer trigger 'destroyed' events if their parent
EditSession has already been destroyed.
These are all really intertwined, so I'm doing them as one commit
since that was the only way to keep the specs green.
If we pass an explicit autoscroll option when selection, we don't want
to autoscroll the cursor. If the option is true, we'll autoscroll to
the middle of the selection. If the option is false, we don't want any
autoscrolling, including to the cursor. The cursor should only autoscroll
when the option is undefined.
Destroying the cursor will cause a redraw, which causes a problem when
we execute it synchronously in specs because destroying the cursor also
destroys the marker associated with the selection. Here we remove the
selection first to avoid this problem.
This commit makes autoscroll a 3-valued property on the cursor. If it
is set to true or false, that setting will stick until the cursor's
next visual update. That means we can explicitly move the cursor with
autoscroll set to false, but also still autoscroll by default when the
cursor's anchor moves on its own.
Any events emitted from DOM nodes should be prefixed with an identifier
for the node that emits them. This eliminates the possibility of ambiguity
when the events bubble up the DOM away from their emitter.
This avoids emitting selection change events when they aren't really needed. This extra event was causing the highlighted line to be updated when it didn't need to be.
