Fix substring length calculation for backward search

[valdaarhun]

Currently, the substring from the beginning of the row till the cursor is picked for backward search. Due to this, the nearest match located prior to the cursor will get skipped when its position lies within the word.

Example:

orange orange
          ^

If the query is "orange" and backward search is performed, the cursor points to the first orange instead of the second orange.

[pflenker]

Thanks! I'm currently rewriting the hecto tutorial and will make sure this change makes its way into it, and that you are properly attributed.

[valdaarhun]

Hi. Sorry for the late reply.

Thanks! I'm currently rewriting the hecto tutorial and will make sure this change makes its way into it, and that you are properly attributed.

That's really nice to hear! And thank you for the tutorial. I really enjoyed working through it. It helped make the rust learning curve much less overwhelming for me.