Basically:
* Use `extend` for class definitions
* Use `new` for object instantiations
That includes some minor code cleanups along the way:
* Updated `Widget`'s docs to make the semantics clearer.
* Removed `should_restrict_JIT` (it's been dead code since https://github.com/koreader/android-luajit-launcher/pull/283)
* Minor refactoring of LuaSettings/LuaData/LuaDefaults/DocSettings to behave (mostly, they are instantiated via `open` instead of `new`) like everything else and handle inheritance properly (i.e., DocSettings is now a proper LuaSettings subclass).
* Default to `WidgetContainer` instead of `InputContainer` for stuff that doesn't actually setup key/gesture events.
* Ditto for explicit `*Listener` only classes, make sure they're based on `EventListener` instead of something uselessly fancier.
* Unless absolutely necessary, do not store references in class objects, ever; only values. Instead, always store references in instances, to avoid both sneaky inheritance issues, and sneaky GC pinning of stale references.
* ReaderUI: Fix one such issue with its `active_widgets` array, with critical implications, as it essentially pinned *all* of ReaderUI's modules, including their reference to the `Document` instance (i.e., that was a big-ass leak).
* Terminal: Make sure the shell is killed on plugin teardown.
* InputText: Fix Home/End/Del physical keys to behave sensibly.
* InputContainer/WidgetContainer: If necessary, compute self.dimen at paintTo time (previously, only InputContainers did, which might have had something to do with random widgets unconcerned about input using it as a baseclass instead of WidgetContainer...).
* OverlapGroup: Compute self.dimen at *init* time, because for some reason it needs to do that, but do it directly in OverlapGroup instead of going through a weird WidgetContainer method that it was the sole user of.
* ReaderCropping: Under no circumstances should a Document instance member (here, self.bbox) risk being `nil`ed!
* Kobo: Minor code cleanups.
This creates a new plugin system which hooks into a handful of reader
operations in order to allow plugins to add language-specific support
where the default reader falls short. The two hooks added are:
* During hold-without-pan taps, language plugins can modify the
selection in order to better match what users expect koreader to
highlight when selecting a single word.
The vast majority of CJK language words are more than one character,
but KOReader treats all CJK characters as a single word by default,
so adding this hook means that readers no longer need to manually
select the whole word every time they need to look something.
* During dictionary lookup, language plugins can propose alternative
candidate words to look up if the selected word could not be found in
the dictionary.
This is pretty necessary for Japanese and Korean, both of which are
highly agglutinative languages and the fuzzy searching system of
StarDict is simply not usable because often the inflection of the
word is so much longer than the dictionary form that sdcv decides to
chop off the actual word and search for the inflection (which yields
useless results).
This system is of particular interest for readers of CJK languages
(without this, looking up words using KOReader was fairly painful) but
this system is designed to be minimal and language-agnostic enough that
other languages could make use of it by creating their own plugins if
the default "whole word" highlight and fuzzy-search system doesn't match
their needs.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
