Support @isset and @endisset directives.

indent/blade.vim

@@ -17,7 +17,7 @@ let b:did_indent = 1
 
 " Doesn't include 'foreach' and 'forelse' because these already get matched by 'for'.
 let s:directives_start = 'if\|else\|unless\|for\|while\|empty\|push\|section\|can\|hasSection\|verbatim\|php\|' .
-            \ 'component\|slot\|prepend\|auth\|guest'
+            \ 'component\|slot\|prepend\|auth\|guest\|isset'
 let s:directives_end = 'else\|end\|empty\|show\|stop\|append\|overwrite'
 
 if exists('g:blade_custom_directives_pairs')

syntax/blade.vim

@@ -32,12 +32,12 @@ syn region  bladeComment    matchgroup=bladeDelimiter start="{{--" end="--}}"  c
 syn keyword bladeKeyword @if @elseif @foreach @forelse @for @while @can @cannot @elsecan @elsecannot @include
     \ @includeIf @each @inject @extends @section @stack @push @unless @yield @parent @hasSection @break @continue
     \ @unset @lang @choice @component @slot @prepend @json @isset @auth @guest @switch @case @includeFirst @empty
-    \ @includeWhen
+    \ @includeWhen @isset
     \ nextgroup=bladePhpParenBlock skipwhite containedin=ALLBUT,@bladeExempt
 
 syn keyword bladeKeyword @else @endif @endunless @endfor @endforeach @endforelse @endwhile @endcan
     \ @endcannot @stop @append @endsection @endpush @show @overwrite @verbatim @endverbatim @endcomponent
-    \ @endslot @endprepend @endisset @endempty @endauth @endguest @endswitch
+    \ @endslot @endprepend @endisset @endempty @endauth @endguest @endswitch endisset
     \ containedin=ALLBUT,@bladeExempt
 
 if exists('g:blade_custom_directives')