Allow same-character matching (fix #102)

commit 9fbba60cee83af1f92a9deebc4b48ca4027d6537
Author: Andy K. Massimino <f8a663@normed.space>
Date:   Fri Nov 27 09:36:11 2020 -0500

    Cleanup for same match

commit 2bf5e26f9e6ecb3f0874426e00cf15dd3f09a11a
Author: Andy K. Massimino <f8a663@normed.space>
Date:   Thu Nov 19 16:10:13 2020 -0500

    WIP same experiments

commit dcc2d874c5b92bccb0d043213264ef31c9b3a033
Author: Andy K. Massimino <f8a663@normed.space>
Date:   Sun Aug 30 11:49:20 2020 -0400

    WIP same char

README.md

@@ -81,13 +81,13 @@ together with other plugins.
 | ------- | -------------------------------- | -------------- | ------------- | ------------- |
 | ([a.1]) | jump between matching words      | :thumbsup:     | :thumbsup:    | :x:           |
 | ([a.2]) | jump to open & close words       | :thumbsup:     | :thumbsup:    | :x:           |
-| ([a.3]) | jump inside                      | :thumbsup:     | :x:           | :x:           |
+| ([a.3]) | jump inside (`z%`)               | :thumbsup:     | :x:           | :x:           |
 | ([b.1]) | full set of text objects         | :thumbsup:     | :question:    | :x:           |
 | ([c.1]) | highlight `()`, `[]`, & `{}`     | :thumbsup:     | :x:           | :thumbsup:    |
 | ([c.2]) | highlight _all_ matches          | :thumbsup:     | :x:           | :x:           |
 | ([c.3]) | display matches off-screen       | :thumbsup:     | :x:           | :x:           |
+| ([c.4]) | show where you are (breadcrumbs) | :thumbsup:     | :x:           | :x:           |
 | ([d.1]) | modern, modular coding style     | :thumbsup:     | :x:           | :x:           |
-| ([d.2]) | actively developed               | :thumbsup:     | :x:           | :x:           |
 
 [a.1]: #a1-jump-between-matching-words
 [a.2]: #a2-jump-to-open-and-close-words
@@ -96,8 +96,8 @@ together with other plugins.
 [c.1]: #c1-highlight---and-
 [c.2]: #c2-highlight-all-matches
 [c.3]: #c3-display-matches-off-screen
+[c.4]: #c4-where-am-i
 [d.1]: #development
-[d.2]: #development
 [inclusive]: #inclusive-and-exclusive-motions
 [exclusive]: #inclusive-and-exclusive-motions
 
@@ -231,9 +231,42 @@ since these commands make sure not to leave stale matches around.
 
 If a open or close which would have been highlighted is on a line
 positioned outside the current window, the match is shown in the
-status line.  If both the open and close match are off-screen, the
+status line or popup window.
+If both the open and close match are off-screen, the
 close match is preferred.
-(See the option `g:matchup_matchparen_offscreen`).
+See the option `g:matchup_matchparen_offscreen` for more details.
+
+For popup style (supported in recent vim and neovim versions):
+
+```vim
+let g:matchup_matchparen_offscreen = {'method': 'popup'}
+```
+
+For status line style (default):
+
+```vim
+let g:matchup_matchparen_offscreen = {'method': 'status'}
+```
+
+#### (c.4) where am I?
+
+If you are lost, you can ask match-up where you are using
+
+    :MatchupWhereAmI?
+
+This echos your position in the code in a breadcrumb-style by finding
+successive matching words, like doing `[%` repeatedly.
+
+It's useful to bind this to a key (not bound by default)
+
+```vim
+nnoremap <c-k> :<c-u>MatchupWhereAmI?<cr>
+```
+
+If you are really lost, you can ask a bit harder to get a more detailed
+print out.
+
+    :MatchupWhereAmI??
 
 ### Inclusive and exclusive motions
 

after/ftplugin/tex_matchup.vim

@@ -71,6 +71,9 @@ function! s:get_match_words()
   " generic environment
   let l:match_words .= ',\\begin\s*{\([^}]*\)}:\\end\s*{\1}'
 
+  " dollar sign math
+  let l:match_words .= ',\$:\$\g{syn;!texMathZoneX}'
+
   return l:match_words
 endfunction
 

autoload/matchup/delim.vim

@@ -563,6 +563,21 @@ function! s:parser_delim_new(lnum, cnum, opts) " {{{1
         continue
       endif
 
+      " handle syntax check- currently used for 'same' matches
+      if has_key(l:extra_entry, 'syn')
+        let l:pat = l:extra_entry.syn
+        if l:pat[0] == '!'
+          let l:pat = l:pat[1:]
+          if matchup#util#in_synstack(l:pat, a:lnum, a:cnum)
+            continue
+          endif
+        else
+          if !matchup#util#in_synstack(l:pat, a:lnum, a:cnum)
+            continue
+          endif
+        endif
+      endif
+
       let l:found = 1
       break
     endfor
@@ -572,8 +587,6 @@ function! s:parser_delim_new(lnum, cnum, opts) " {{{1
     break
   endfor
 
-  " reset ignorecase (defunct)
-
   if !l:found
     return {}
   endif
@@ -716,15 +729,19 @@ function! s:get_matching_delims(down, stopline) dict " {{{1
   let l:open = l:ic . l:open
   let l:close = l:ic . l:close
 
-  let [l:lnum_corr, l:cnum_corr] = searchpairpos(l:open, '', l:close,
-        \ 'n'.l:flags, l:skip, l:stopline, matchup#perf#timeout())
+  " handle 'same' matches (TODO refactor to separate parser)
+  if l:open == l:close
+    let [l:lnum_corr, l:cnum_corr] = searchpos(l:open,
+          \ 'n'.l:flags, l:stopline, matchup#perf#timeout(), l:skip)
+  else
+    let [l:lnum_corr, l:cnum_corr] = searchpairpos(l:open, '', l:close,
+          \ 'n'.l:flags, l:skip, l:stopline, matchup#perf#timeout())
+  endif
 
   call matchup#perf#toc('get_matching_delims', 'initial_pair')
 
   " if nothing found, bail immediately
   if l:lnum_corr == 0
-    " reset ignorecase (defunct)
-
     return [['', 0, 0]]
   endif
 
@@ -740,8 +757,6 @@ function! s:get_matching_delims(down, stopline) dict " {{{1
   let l:matches = matchlist(getline(l:lnum_corr), l:re_anchored)
   let l:match_corr = l:matches[0]
 
-  " reset ignorecase (defunct)
-
   " store these in these groups
   if a:down
     " let l:id = len(self.regextwo.mid_list)+1
@@ -806,8 +821,6 @@ function! s:get_matching_delims(down, stopline) dict " {{{1
     call add(l:list, [l:match, l:lnum, l:cnum])
   endwhile
 
-  " reset ignorecase (defunct)
-
   call add(l:list, [l:match_corr, l:lnum_corr, l:cnum_corr])
 
   if !a:down

autoload/matchup/re.vim

@@ -16,7 +16,7 @@ let g:matchup#re#zs = s:nbsl . '\\zs'
 " \ze atom
 let g:matchup#re#ze = s:nbsl . '\\ze'
 
-" \g{special}, \g{special:arg}
+" \g{special}, \g{special;arg}
 let g:matchup#re#gspec = s:nbsl . '\\g{\(\w\+\);\?\(.\{-}\)\?}'
 
 " vim: fdm=marker sw=2

autoload/matchup/util.vim

@@ -46,6 +46,15 @@ function! matchup#util#in_syntax(name, ...) " {{{1
 endfunction
 
 " }}}1
+function! matchup#util#in_synstack(name, ...) abort " {{{1
+  let l:pos = a:0 > 0 ? [a:1, a:2] : [line('.'), col('.')]
+  let l:syn = map(synstack(l:pos[0], l:pos[1]),
+        \ "synIDattr(v:val, 'name')")
+  return match(l:syn, '^' . a:name) >= 0
+endfunction
+
+" }}}1
+
 function! matchup#util#in_whitespace(...) " {{{1
   let l:pos = a:0 > 0 ? [a:1, a:2] : [line('.'), col('.')]
   return matchstr(getline(l:pos[0]), '\%'.l:pos[1].'c.') =~# '\s'