Check test code coverage

[hluk]

1. Compile with --coverage flag,
2. run tests and
3. check which code wasn't executed, i.e. untested code.

[hluk]

Most of the code is covered by automatic tests.

Untested and possibly difficult to test:

• sending key press events and transforming to key name -- unfortunately, it's not possible since key press with QTest doesn't generate text --,
• passing next key press to editor with ,,
• disabling and enabling FakeVim,
• timeout for user mappings (need at least second to timeout),
• cooperation with external search tool,
• scrolling (needs visual confirmation),
• movement on current screen with H and similar (needs visual confirmation),
• working with command line (needs visual confirmation),
• exporting selection visually to editor widget (needs visual confirmation),
• splitting and focusing different editors,
• ZZ, ZQ,
• :w, :r, :source.

Should be tested:

• emitted signals for various functionality -- highlights, folds, move to matching parenthesis and similar, status messages etc. --,
• !, :! (with and without range, i.e. visual selection),
• ==, <=, >=,
• indentation commands in visual mode,
• jump to unknown mark (should cancel command?),
• [{, ]}, [(, ]),
• ; (repeat last f or t movement),
• |,
• line movement with +, -, Enter,
• E, gE, `,
• &,
• X,
• D and X in all visual modes,
• i on empty line,
• gI,
• R (enter replace mode),
• y in visual char mode,
• ~, u, U in visual line and block modes,
• u, U without visual mode,
• r in visual line mode,
• r<CR>,
• <TAB> in insert mode,
• <C-d> in insert mode,
• <S-INSERT> in insert mode,
• /<CR> for last search,
• complicated line address (and range) in Ex mode, e.g. combination of -3+5-8+13, ++ (+2), ", ',
• p in visual line and block mode,
• A in some visual modes.