patch 8.2.4197: cannot use an import in the "expr" part of 'spellsuggest'

Problem:    Cannot use an import in the "expr" part of 'spellsuggest'.
Solution:   Set the script context when evaluating "expr" of 'spellsuggest'.

src/evalvars.c

@@ -495,12 +495,17 @@ eval_spell_expr(char_u *badword, char_u *expr)
     typval_T	rettv;
     list_T	*list = NULL;
     char_u	*p = skipwhite(expr);
+    sctx_T	saved_sctx = current_sctx;
+    sctx_T	*ctx;
 
     // Set "v:val" to the bad word.
     prepare_vimvar(VV_VAL, &save_val);
     set_vim_var_string(VV_VAL, badword, -1);
     if (p_verbose == 0)
 	++emsg_off;
+    ctx = get_option_sctx("spellsuggest");
+    if (ctx != NULL)
+	current_sctx = *ctx;
 
     if (eval1(&p, &rettv, &EVALARG_EVALUATE) == OK)
     {
@@ -514,6 +519,7 @@ eval_spell_expr(char_u *badword, char_u *expr)
 	--emsg_off;
     clear_tv(get_vim_var_tv(VV_VAL));
     restore_vimvar(VV_VAL, &save_val);
+    current_sctx = saved_sctx;
 
     return list;
 }

src/testdir/test_vim9_import.vim

@@ -936,6 +936,34 @@ def Test_import_in_charconvert()
   set charconvert&
 enddef
 
+func Test_import_in_spellsuggest_expr()
+  CheckFeature spell
+  call Run_Test_import_in_spellsuggest_expr()
+endfunc
+
+def Run_Test_import_in_spellsuggest_expr()
+  var lines =<< trim END
+      vim9script
+      export def MySuggest(): list<any>
+        return [['Fox', 8], ['Fop', 9]]
+      enddef
+  END
+  writefile(lines, 'Xsuggest.vim')
+
+  lines =<< trim END
+      vim9script
+      import './Xsuggest.vim' as sugg
+      set spell spellsuggest=expr:sugg.MySuggest()
+  END
+  CheckScriptSuccess(lines)
+
+  set verbose=1  # report errors
+  call assert_equal(['Fox', 'Fop'], spellsuggest('Fo', 2))
+
+  delete('Xsuggest.vim')
+  set nospell spellsuggest& verbose=0
+enddef
+
 def Test_export_fails()
   CheckScriptFailure(['export var some = 123'], 'E1042:')
   CheckScriptFailure(['vim9script', 'export var g:some'], 'E1022:')

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4197,
 /**/
     4196,
 /**/