Fix weird indentation issue of yaml

indent/yaml.vim

@@ -0,0 +1,159 @@
+if !exists('g:polyglot_disabled') || index(g:polyglot_disabled, 'yaml') == -1
+
+" Vim indent file
+" Language:         YAML
+" Maintainer:       Nikolai Pavlov <zyx.vim@gmail.com>
+" Last Change:	    2019 Sep 28
+
+" Only load this indent file when no other was loaded.
+if exists('b:did_indent')
+  finish
+endif
+
+let s:save_cpo = &cpo
+set cpo&vim
+
+let b:did_indent = 1
+
+setlocal indentexpr=GetYAMLIndent(v:lnum)
+setlocal indentkeys=!^F,o,O,0#,0},0],<:>,0-
+setlocal nosmartindent
+
+let b:undo_indent = 'setlocal indentexpr< indentkeys< smartindent<'
+
+" Only define the function once.
+if exists('*GetYAMLIndent')
+    finish
+endif
+
+function s:FindPrevLessIndentedLine(lnum, ...)
+    let prevlnum = prevnonblank(a:lnum-1)
+    let curindent = a:0 ? a:1 : indent(a:lnum)
+    while           prevlnum
+                \&&  indent(prevlnum) >=  curindent
+                \&& getline(prevlnum) !~# '^\s*#'
+        let prevlnum = prevnonblank(prevlnum-1)
+    endwhile
+    return prevlnum
+endfunction
+
+function s:FindPrevLEIndentedLineMatchingRegex(lnum, regex)
+    let plilnum = s:FindPrevLessIndentedLine(a:lnum, indent(a:lnum)+1)
+    while plilnum && getline(plilnum) !~# a:regex
+        let plilnum = s:FindPrevLessIndentedLine(plilnum)
+    endwhile
+    return plilnum
+endfunction
+
+let s:mapkeyregex='\v^\s*\#@!\S@=%(\''%([^'']|\''\'')*\'''.
+                \                 '|\"%([^"\\]|\\.)*\"'.
+                \                 '|%(%(\:\ )@!.)*)\:%(\ |$)'
+let s:liststartregex='\v^\s*%(\-%(\ |$))'
+
+let s:c_ns_anchor_char = '\v%([\n\r\uFEFF \t,[\]{}]@!\p)'
+let s:c_ns_anchor_name = s:c_ns_anchor_char.'+'
+let s:c_ns_anchor_property =  '\v\&'.s:c_ns_anchor_name
+
+let s:ns_word_char = '\v[[:alnum:]_\-]'
+let s:ns_tag_char  = '\v%(%\x\x|'.s:ns_word_char.'|[#/;?:@&=+$.~*''()])'
+let s:c_named_tag_handle     = '\v\!'.s:ns_word_char.'+\!'
+let s:c_secondary_tag_handle = '\v\!\!'
+let s:c_primary_tag_handle   = '\v\!'
+let s:c_tag_handle = '\v%('.s:c_named_tag_handle.
+            \            '|'.s:c_secondary_tag_handle.
+            \            '|'.s:c_primary_tag_handle.')'
+let s:c_ns_shorthand_tag = '\v'.s:c_tag_handle . s:ns_tag_char.'+'
+let s:c_non_specific_tag = '\v\!'
+let s:ns_uri_char  = '\v%(%\x\x|'.s:ns_word_char.'\v|[#/;?:@&=+$,.!~*''()[\]])'
+let s:c_verbatim_tag = '\v\!\<'.s:ns_uri_char.'+\>'
+let s:c_ns_tag_property = '\v'.s:c_verbatim_tag.
+            \               '\v|'.s:c_ns_shorthand_tag.
+            \               '\v|'.s:c_non_specific_tag
+
+let s:block_scalar_header = '\v[|>]%([+-]?[1-9]|[1-9]?[+-])?'
+
+function GetYAMLIndent(lnum)
+    if a:lnum == 1 || !prevnonblank(a:lnum-1)
+        return 0
+    endif
+
+    let prevlnum = prevnonblank(a:lnum-1)
+    let previndent = indent(prevlnum)
+
+    let line = getline(a:lnum)
+    if line =~# '^\s*#' && getline(a:lnum-1) =~# '^\s*#'
+        " Comment blocks should have identical indent
+        return previndent
+    elseif line =~# '^\s*[\]}]'
+        " Lines containing only closing braces should have previous indent
+        return indent(s:FindPrevLessIndentedLine(a:lnum))
+    endif
+
+    " Ignore comment lines when calculating indent
+    while getline(prevlnum) =~# '^\s*#'
+        let prevlnum = prevnonblank(prevlnum-1)
+        if !prevlnum
+            return previndent
+        endif
+    endwhile
+
+    let prevline = getline(prevlnum)
+    let previndent = indent(prevlnum)
+
+    " Any examples below assume that shiftwidth=2
+    if prevline =~# '\v[{[:]$|[:-]\ [|>][+\-]?%(\s+\#.*|\s*)$'
+        " Mapping key:
+        "     nested mapping: ...
+        "
+        " - {
+        "     key: [
+        "         list value
+        "     ]
+        " }
+        "
+        " - |-
+        "     Block scalar without indentation indicator
+        return previndent+shiftwidth()
+    elseif prevline =~# '\v[:-]\ [|>]%(\d+[+\-]?|[+\-]?\d+)%(\#.*|\s*)$'
+        " - |+2
+        "   block scalar with indentation indicator
+        "#^^ indent+2, not indent+shiftwidth
+        return previndent + str2nr(matchstr(prevline,
+                    \'\v([:-]\ [|>])@<=[+\-]?\d+%([+\-]?%(\s+\#.*|\s*)$)@='))
+    elseif prevline =~# '\v\"%([^"\\]|\\.)*\\$'
+        "    "Multiline string \
+        "     with escaped end"
+        let qidx = match(prevline, '\v\"%([^"\\]|\\.)*\\')
+        return virtcol([prevlnum, qidx+1])
+    elseif line =~# s:liststartregex
+        " List line should have indent equal to previous list line unless it was 
+        " caught by one of the previous rules
+        return indent(s:FindPrevLEIndentedLineMatchingRegex(a:lnum,
+                    \                                       s:liststartregex))
+    elseif line =~# s:mapkeyregex
+        " Same for line containing mapping key
+        let prevmapline = s:FindPrevLEIndentedLineMatchingRegex(a:lnum,
+                    \                                           s:mapkeyregex)
+        if getline(prevmapline) =~# '^\s*- '
+            return indent(prevmapline) + 2
+        else
+            return indent(prevmapline)
+        endif
+    elseif prevline =~# '^\s*- '
+        " - List with
+        "   multiline scalar
+        return previndent+2
+    elseif prevline =~# s:mapkeyregex . '\v\s*%(%('.s:c_ns_tag_property.
+                \                              '\v|'.s:c_ns_anchor_property.
+                \                              '\v|'.s:block_scalar_header.
+                \                             '\v)%(\s+|\s*%(\#.*)?$))*'
+        " Mapping with: value
+        "     that is multiline scalar
+        return previndent+shiftwidth()
+    endif
+    return previndent
+endfunction
+
+let &cpo = s:save_cpo
+
+endif