py/repl: Generalise REPL autocomplete to use qstr probing.
This patch changes the way REPL autocomplete finds matches. It now probes the target object for all qstrs via mp_load_method_maybe to look for a match with the given input string. Similar to how the builtin dir() function works, this new algorithm now find all methods and instances of user-defined classes including attributes of their parent classes. This helps a lot at the REPL prompt for user-discovery and to autocomplete names even for classes that are derived. The downside is that this new algorithm is slower than the previous one, and in particular will be slower the more qstrs there are in the system. But because REPL autocomplete is primarily used in an interactive way it is not that important to make it fast, as long as it is "fast enough" compared to human reaction. On a slow microcontroller (CPU running at 16MHz) the autocomplete time for a list of 35 names in the outer namespace (pressing tab at a bare prompt) takes about 160ms with this algorithm, compared to about 40ms for the previous implementation (this time includes the actual printing of the names as well). This time of 160ms is very reasonable especially given the new functionality of listing all the names. This patch also decreases code size by: bare-arm: +0 minimal x86: -128 unix x64: -128 unix nanbox: -224 stm32: -88 cc3200: -80 esp8266: -92 esp32: -84
Showing with 39 additions and 55 deletions