[Bug Report] hi link groups inherits definition from former same name group

[laggardkernel]

Formerly posted here

hi! link merges definition from former hi group (not linked). And our clearance at the top hi clear is enough to solve the problem. Cause hi clear groupname and hi clear behaves differently. The later will load default (vim builtin?) color scheme definitions.

[laggardkernel]

It's the buggy hi wrapper function X and XAPI. When define a new highlight group definition, we should clear former hi definition.

Let's say hi Constant guifg=#000000, all the undefined part like ctermfg, ctermbg, cterm, guibg, gui will reuse former definition. The correct way is to pass =NONE for these values.

[laggardkernel]

I've fixed most of the part now. But should whether to add back bold attribute back. Keep the following lines for myself in case later I need to make some groups bold.

call <sid>X('Todo',           s:syntax_fg,     s:hue_6_2,   'bold')

MoreMsg        xxx ctermfg=2 gui=bold guifg=SeaGreen
                   links to OneSyntaxFg
ModeMsg        xxx cterm=bold gui=bold
                   links to OneSyntaxFg

Question       xxx ctermfg=2 gui=bold guifg=SeaGreen
                   links to OneHue2

Type           xxx ctermfg=2 gui=bold guifg=SeaGreen
                   links to OneHue62

Statement      xxx ctermfg=130 gui=bold guifg=Brown
                   links to OneHue3