Fix #241 - Add support for import package

README.md

@@ -49,6 +49,9 @@ disabled if desired.
   - Support for `listings` package
   - Support for `minted` package
   - Support for `dot2tex` with nested syntax highlighting
+- Support for multi-file project packages
+  - [import](http://ctan.uib.no/macros/latex/contrib/import/import.pdf)
+  - [subfiles](http://ctan.uib.no/macros/latex/contrib/import/import.pdf) (partly)
 
 See the documentation for a more thorough introduction of the plugin (e.g. `:h
 vimtex`).

autoload/vimtex.vim

@@ -468,7 +468,7 @@ function! s:get_main() " {{{1
   endif
 
   "
-  " Search for main file recursively through \input and \include specifiers
+  " Search for main file recursively through include specifiers
   "
   let main = s:get_main_recurse(expand('%:p'))
   if filereadable(main)
@@ -528,15 +528,20 @@ function! s:get_main_recurse(file) " {{{1
   let l:candidates = split(globpath(fnameescape(l:dirs), '*.tex'), '\n')
 
   "
-  " Search through candidates for \include{current file}
+  " Search through candidates
   "
   for l:file in l:candidates
     " Avoid infinite recursion (checking the same file repeatedly)
     if l:file == a:file | continue | endif
 
-    if len(filter(readfile(l:file), 'v:val =~ ''\v\\(input|include)\{'
-          \ . '\s*((.*)\/)?'
-          \ . fnamemodify(a:file, ':t:r') . '(\.tex)?\s*''')) > 0
+    let l:file_re = '\s*((.*)\/)?' . fnamemodify(a:file, ':t:r')
+
+    let l:filter  = 'v:val =~# ''\v'
+    let l:filter .= '\\%(input|include)\{' . l:file_re
+    let l:filter .= '|\\subimport\{[^\}]*\}\{' . l:file_re
+    let l:filter .= ''''
+
+    if len(filter(readfile(l:file), l:filter)) > 0
       return s:get_main_recurse(l:file)
     endif
   endfor

autoload/vimtex/parser.vim

@@ -9,7 +9,7 @@ endfunction
 
 " }}}1
 function! vimtex#parser#init_script() " {{{1
-  let s:input_line_tex = '\v^\s*\\%(input|include)\s*\{'
+  let s:input_line_tex = '\v^\s*\\%(input|include|subimport)\s*\{'
   let s:input_line_aux = '\\@input{'
 endfunction
 
@@ -83,7 +83,15 @@ endfunction
 " Input line parsers
 "
 function! s:input_line_parser_tex(line, file) " {{{1
+  " Handle \space commands
   let l:file = substitute(a:line, '\\space\s*', ' ', 'g')
+
+  " Hande subimport commands
+  if a:line =~# '\\subimport'
+    let l:file = substitute(l:file, '}\s*{', '', 'g')
+  endif
+
+  " Parse file name
   let l:file = matchstr(l:file, s:input_line_tex . '\zs[^\}]+\ze}')
 
   " Trim whitespaces and quotes from beginning/end of string

doc/vimtex.txt

@@ -112,6 +112,9 @@ Feature overview~
   - Support for `listings` package
   - Support for `minted` package
   - Support for `dot2tex` with nested syntax highlighting
+- Support for multi-file project packages
+  - `import`
+  - `subfiles` (partly)
 
 ------------------------------------------------------------------------------
 Requirements~
@@ -201,6 +204,17 @@ Subfiles~
   Note that this is a special case in that it is only relevant for users who
   use the `subfiles` package.
 
+                                                                 *vimtex-import*
+Import~
+  |vimtex| also supports the `import` package, in that it should correctly
+  recognize the main file from sub files that are included through the
+  `subimport` command, e.g. >
+
+    \subimport{chapters/}{chapter1.tex}
+<
+  The support also extends into correctly parsing the project for table of
+  contents.
+
                                                                  *b:vimtex_main*
 Buffer variable~
   Finally, the main file may be specified through the buffer variable

test/issue/241/main.tex

@@ -4,5 +4,5 @@
 \begin{document}
 \subimport{preamble/}{preamble.tex}
 \cleardoublepage
-\subimport{chapter/}{chapter.tex}
+\subimport{parts/}{chapter.tex}
 \end{document}