Follow file paths without extension

When a file path under the cursor does not have an extension (which is
quite common in `import` statements in JavaScript projects), Vim will
now try to append it so the `gf` command can function properly.

This has only been applied to JavaScript and TypeScript files (including
their JSX flavours).

.vimrc

@@ -40,6 +40,8 @@ let g:prettier#config#bracket_spacing = 'true'
 let g:prettier#config#arrow_parens = 'avoid'
 let g:prettier#config#trailing_comma = 'none'
 
+au BufNewFile,BufRead *.jsx set filetype=javascript
+au BufNewFile,BufRead *.tsx set filetype=typescript
 au BufNewFile,BufRead *.ejs,*.hbs set filetype=html
 au BufNewFile,BufRead *.js.ejs set filetype=javascript
 au BufNewFile,BufRead *.json.ejs set filetype=json
@@ -96,6 +98,21 @@ nnoremap <C-l> :call LineNumberToggle()<CR>
 :au FocusGained * :set relativenumber
 " End: line number management
 
+" Follow file paths without extensions
+augroup suffixes
+  autocmd!
+
+  let fileTypeToExtensions = {
+    \'javascript': '.js,.jsx,.json',
+    \'typescript': '.ts,.tsx'
+  \}
+
+  for [fileType, extensions] in items(fileTypeToExtensions)
+    execute 'autocmd FileType ' . fileType . ' setlocal suffixesadd=' . extensions
+    unlet fileType extensions
+  endfor
+augroup END
+
 " Display buffer list in the alphabetical order
 command! -bang Ls redir @" | silent ls<bang> | redir END | echo " " |
  \ perl {

README.md

@@ -32,6 +32,8 @@ cursors)
 
 **Ctrl-l** - toggle line numbers (including relative to the current line)
 
+**gf** - follow local `import` paths even if they don't have e.g. the `.js` extension
+
 **:Ls** - show file buffer list ordered alphabetically
 
 # Working with plugins