Implement :VimwikiRebuildTags to rebuild metadata for all pages in current wiki

autoload/vimwiki/base.vim

@@ -1945,10 +1945,8 @@ let s:TAGS_METADATA_FILE_NAME = '.tags'
 "   a:full_rebuild == 1: re-scan entire wiki
 "   a:full_rebuild == 0: only re-scan current page
 function! vimwiki#base#update_tags(full_rebuild) "{{{
-  if a:full_rebuild
-    throw 'vimwiki#base#update_tags1: full rebuild not supported yet'
-  endif
-  "
+  if !a:full_rebuild
+    " Updating for one page (current)
     let page_name = expand('%:t:r')
     " Collect tags in current file
     let tags = vimwiki#base#scan_tags(getline(1, '$'), page_name)
@@ -1960,6 +1958,16 @@ function! vimwiki#base#update_tags(full_rebuild) "{{{
     let metadata = vimwiki#base#merge_tags(metadata, tags)
     " Save
     call vimwiki#base#write_tags_metadata(metadata)
+  else " full rebuild
+    let files = s:find_files(g:vimwiki_current_idx, 0)
+    let metadata = []
+    for file in files
+      let page_name = fnamemodify(file, ':t:r')
+      let tags = vimwiki#base#scan_tags(readfile(file), page_name)
+      let metadata = vimwiki#base#merge_tags(metadata, tags)
+    endfor
+    call vimwiki#base#write_tags_metadata(metadata)
+  endif
 endfunction " }}}
 
 " vimwiki#base#scan_tags

doc/vimwiki.txt

@@ -704,6 +704,10 @@ il                      A single list item.
     files are reachable from the index file. Errors are shown in the quickfix
     window.
 
+*:VimwikiRebuildTags*
+    Iterates over all files in a current wiki and rebuilds tags metadata (to
+    enable tags related commands).
+
 ==============================================================================
 5. Wiki syntax                                                *vimwiki-syntax*
 

ftplugin/vimwiki.vim

@@ -302,6 +302,9 @@ command! -buffer VimwikiTableMoveColumnRight call vimwiki#tbl#move_column_right(
 command! -buffer VimwikiDiaryNextDay call vimwiki#diary#goto_next_day()
 command! -buffer VimwikiDiaryPrevDay call vimwiki#diary#goto_prev_day()
 
+" tags commands
+command! -buffer VimwikiRebuildTags call vimwiki#base#update_tags(1)
+
 " COMMANDS }}}
 
 " KEYBINDINGS {{{