vim-patch:9.0.0335: checks for Dictionary argument often give a vague error (#23309)

Problem:    Checks for Dictionary argument often give a vague error message.
Solution:   Give a useful error message. (Yegappan Lakshmanan, closes vim/vim#11009)

https://github.com/vim/vim/commit/04c4c5746e15884768d2cb41370c3276a196cd4c

Cherry-pick removal of E922 from docs from patch 9.0.1403.

Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>

7 files changed, 79 insertions, 78 deletions

diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 35738cdfa9..bc33697c62 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -5357,8 +5357,7 @@ void common_function(typval_T *argvars, typval_T *rettv, bool is_funcref)
         arg_idx = 1;
       }
       if (dict_idx > 0) {
-        if (argvars[dict_idx].v_type != VAR_DICT) {
-          emsg(_("E922: expected a dict"));
+        if (tv_check_for_dict_arg(argvars, dict_idx) == FAIL) {
           xfree(name);
           goto theend;
         }
@@ -8726,7 +8725,7 @@ int typval_compare(typval_T *typ1, typval_T *typ2, exprtype_T type, bool ic)
   const bool type_is = type == EXPR_IS || type == EXPR_ISNOT;
 
   if (type_is && typ1->v_type != typ2->v_type) {
-    // For "is" a different type always means false, for "notis"
+    // For "is" a different type always means false, for "isnot"
     // it means true.
     n1 = type == EXPR_ISNOT;
   } else if (typ1->v_type == VAR_BLOB || typ2->v_type == VAR_BLOB) {
diff --git a/src/nvim/eval/funcs.c b/src/nvim/eval/funcs.c
index d903d498e7..2a5f1cb720 100644
--- a/src/nvim/eval/funcs.c
+++ b/src/nvim/eval/funcs.c
@@ -597,8 +597,7 @@ static void f_call(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 
   dict_T *selfdict = NULL;
   if (argvars[2].v_type != VAR_UNKNOWN) {
-    if (argvars[2].v_type != VAR_DICT) {
-      emsg(_(e_dictreq));
+    if (tv_check_for_dict_arg(argvars, 2) == FAIL) {
       if (owned) {
         func_unref(func);
       }
@@ -7359,8 +7358,7 @@ static void f_setcharpos(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 
 static void f_setcharsearch(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 {
-  if (argvars[0].v_type != VAR_DICT) {
-    emsg(_(e_dictreq));
+  if (tv_check_for_dict_arg(argvars, 0) == FAIL) {
     return;
   }
 
@@ -7631,8 +7629,7 @@ static void f_settagstack(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   }
 
   // second argument: dict with items to set in the tag stack
-  if (argvars[1].v_type != VAR_DICT) {
-    emsg(_(e_dictreq));
+  if (tv_check_for_dict_arg(argvars, 1) == FAIL) {
     return;
   }
   dict_T *d = argvars[1].vval.v_dict;
@@ -8987,11 +8984,10 @@ static void f_timer_start(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   }
 
   if (argvars[2].v_type != VAR_UNKNOWN) {
-    dict_T *dict = argvars[2].vval.v_dict;
-    if (argvars[2].v_type != VAR_DICT || dict == NULL) {
-      semsg(_(e_invarg2), tv_get_string(&argvars[2]));
+    if (tv_check_for_nonnull_dict_arg(argvars, 2) == FAIL) {
       return;
     }
+    dict_T *dict = argvars[2].vval.v_dict;
     dictitem_T *const di = tv_dict_find(dict, S_LEN("repeat"));
     if (di != NULL) {
       repeat = (int)tv_get_number(&di->di_tv);
diff --git a/src/nvim/eval/typval.c b/src/nvim/eval/typval.c
index 357ef6414d..e4b809d98d 100644
--- a/src/nvim/eval/typval.c
+++ b/src/nvim/eval/typval.c
@@ -60,6 +60,8 @@ static const char e_invalid_value_for_blob_nr[]
   = N_("E1239: Invalid value for blob: %d");
 static const char e_string_or_function_required_for_argument_nr[]
   = N_("E1256: String or function required for argument %d");
+static const char e_non_null_dict_required_for_argument_nr[]
+  = N_("E1297: Non-NULL Dictionary required for argument %d");
 
 bool tv_in_free_unref_items = false;
 
@@ -1232,8 +1234,7 @@ static void do_sort_uniq(typval_T *argvars, typval_T *rettv, bool sort)
 
       if (argvars[2].v_type != VAR_UNKNOWN) {
         // optional third argument: {dict}
-        if (argvars[2].v_type != VAR_DICT) {
-          emsg(_(e_dictreq));
+        if (tv_check_for_dict_arg(argvars, 2) == FAIL) {
           goto theend;
         }
         info.item_compare_selfdict = argvars[2].vval.v_dict;
@@ -2993,10 +2994,10 @@ void f_values(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 /// "has_key()" function
 void f_has_key(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 {
-  if (argvars[0].v_type != VAR_DICT) {
-    emsg(_(e_dictreq));
+  if (tv_check_for_dict_arg(argvars, 0) == FAIL) {
     return;
   }
+
   if (argvars[0].vval.v_dict == NULL) {
     return;
   }
@@ -4051,6 +4052,20 @@ int tv_check_for_dict_arg(const typval_T *const args, const int idx)
   return OK;
 }
 
+/// Give an error and return FAIL unless "args[idx]" is a non-NULL dict.
+int tv_check_for_nonnull_dict_arg(const typval_T *const args, const int idx)
+  FUNC_ATTR_NONNULL_ALL FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_PURE
+{
+  if (tv_check_for_dict_arg(args, idx) == FAIL) {
+    return FAIL;
+  }
+  if (args[idx].vval.v_dict == NULL) {
+    semsg(_(e_non_null_dict_required_for_argument_nr), idx + 1);
+    return FAIL;
+  }
+  return OK;
+}
+
 /// Check for an optional dict argument at "idx"
 int tv_check_for_opt_dict_arg(const typval_T *const args, const int idx)
   FUNC_ATTR_NONNULL_ALL FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_PURE
diff --git a/src/nvim/eval/window.c b/src/nvim/eval/window.c
index 25de236d90..9976c56879 100644
--- a/src/nvim/eval/window.c
+++ b/src/nvim/eval/window.c
@@ -651,8 +651,7 @@ void f_win_splitmove(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
     dict_T *d;
     dictitem_T *di;
 
-    if (argvars[2].v_type != VAR_DICT || argvars[2].vval.v_dict == NULL) {
-      emsg(_(e_invarg));
+    if (tv_check_for_nonnull_dict_arg(argvars, 2) == FAIL) {
       return;
     }
 
@@ -796,51 +795,50 @@ void f_winrestcmd(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 /// "winrestview()" function
 void f_winrestview(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 {
-  dict_T *dict = argvars[0].vval.v_dict;
+  if (tv_check_for_nonnull_dict_arg(argvars, 0) == FAIL) {
+    return;
+  }
 
-  if (argvars[0].v_type != VAR_DICT || dict == NULL) {
-    emsg(_(e_invarg));
-  } else {
-    dictitem_T *di;
-    if ((di = tv_dict_find(dict, S_LEN("lnum"))) != NULL) {
-      curwin->w_cursor.lnum = (linenr_T)tv_get_number(&di->di_tv);
-    }
-    if ((di = tv_dict_find(dict, S_LEN("col"))) != NULL) {
-      curwin->w_cursor.col = (colnr_T)tv_get_number(&di->di_tv);
-    }
-    if ((di = tv_dict_find(dict, S_LEN("coladd"))) != NULL) {
-      curwin->w_cursor.coladd = (colnr_T)tv_get_number(&di->di_tv);
-    }
-    if ((di = tv_dict_find(dict, S_LEN("curswant"))) != NULL) {
-      curwin->w_curswant = (colnr_T)tv_get_number(&di->di_tv);
-      curwin->w_set_curswant = false;
-    }
-    if ((di = tv_dict_find(dict, S_LEN("topline"))) != NULL) {
-      set_topline(curwin, (linenr_T)tv_get_number(&di->di_tv));
-    }
-    if ((di = tv_dict_find(dict, S_LEN("topfill"))) != NULL) {
-      curwin->w_topfill = (int)tv_get_number(&di->di_tv);
-    }
-    if ((di = tv_dict_find(dict, S_LEN("leftcol"))) != NULL) {
-      curwin->w_leftcol = (colnr_T)tv_get_number(&di->di_tv);
-    }
-    if ((di = tv_dict_find(dict, S_LEN("skipcol"))) != NULL) {
-      curwin->w_skipcol = (colnr_T)tv_get_number(&di->di_tv);
-    }
+  dict_T *dict = argvars[0].vval.v_dict;
+  dictitem_T *di;
+  if ((di = tv_dict_find(dict, S_LEN("lnum"))) != NULL) {
+    curwin->w_cursor.lnum = (linenr_T)tv_get_number(&di->di_tv);
+  }
+  if ((di = tv_dict_find(dict, S_LEN("col"))) != NULL) {
+    curwin->w_cursor.col = (colnr_T)tv_get_number(&di->di_tv);
+  }
+  if ((di = tv_dict_find(dict, S_LEN("coladd"))) != NULL) {
+    curwin->w_cursor.coladd = (colnr_T)tv_get_number(&di->di_tv);
+  }
+  if ((di = tv_dict_find(dict, S_LEN("curswant"))) != NULL) {
+    curwin->w_curswant = (colnr_T)tv_get_number(&di->di_tv);
+    curwin->w_set_curswant = false;
+  }
+  if ((di = tv_dict_find(dict, S_LEN("topline"))) != NULL) {
+    set_topline(curwin, (linenr_T)tv_get_number(&di->di_tv));
+  }
+  if ((di = tv_dict_find(dict, S_LEN("topfill"))) != NULL) {
+    curwin->w_topfill = (int)tv_get_number(&di->di_tv);
+  }
+  if ((di = tv_dict_find(dict, S_LEN("leftcol"))) != NULL) {
+    curwin->w_leftcol = (colnr_T)tv_get_number(&di->di_tv);
+  }
+  if ((di = tv_dict_find(dict, S_LEN("skipcol"))) != NULL) {
+    curwin->w_skipcol = (colnr_T)tv_get_number(&di->di_tv);
+  }
 
-    check_cursor();
-    win_new_height(curwin, curwin->w_height);
-    win_new_width(curwin, curwin->w_width);
-    changed_window_setting();
+  check_cursor();
+  win_new_height(curwin, curwin->w_height);
+  win_new_width(curwin, curwin->w_width);
+  changed_window_setting();
 
-    if (curwin->w_topline <= 0) {
-      curwin->w_topline = 1;
-    }
-    if (curwin->w_topline > curbuf->b_ml.ml_line_count) {
-      curwin->w_topline = curbuf->b_ml.ml_line_count;
-    }
-    check_topfill(curwin, true);
+  if (curwin->w_topline <= 0) {
+    curwin->w_topline = 1;
+  }
+  if (curwin->w_topline > curbuf->b_ml.ml_line_count) {
+    curwin->w_topline = curbuf->b_ml.ml_line_count;
   }
+  check_topfill(curwin, true);
 }
 
 /// "winsaveview()" function
diff --git a/src/nvim/mapping.c b/src/nvim/mapping.c
index c1565a84f5..f88c0deb87 100644
--- a/src/nvim/mapping.c
+++ b/src/nvim/mapping.c
@@ -2204,8 +2204,7 @@ void f_mapset(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   const int mode = get_map_mode((char **)&which, 0);
   const bool is_abbr = tv_get_number(&argvars[1]) != 0;
 
-  if (argvars[2].v_type != VAR_DICT) {
-    emsg(_(e_dictreq));
+  if (tv_check_for_dict_arg(argvars, 2) == FAIL) {
     return;
   }
   dict_T *d = argvars[2].vval.v_dict;
diff --git a/src/nvim/search.c b/src/nvim/search.c
index 694c4cad52..50e72eee86 100644
--- a/src/nvim/search.c
+++ b/src/nvim/search.c
@@ -2772,8 +2772,7 @@ void f_searchcount(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
     dictitem_T *di;
     bool error = false;
 
-    if (argvars[0].v_type != VAR_DICT || argvars[0].vval.v_dict == NULL) {
-      emsg(_(e_dictreq));
+    if (tv_check_for_nonnull_dict_arg(argvars, 0) == FAIL) {
       return;
     }
     dict = argvars[0].vval.v_dict;
@@ -3348,8 +3347,7 @@ static void do_fuzzymatch(const typval_T *const argvars, typval_T *const rettv,
   bool matchseq = false;
   long max_matches = 0;
   if (argvars[2].v_type != VAR_UNKNOWN) {
-    if (argvars[2].v_type != VAR_DICT || argvars[2].vval.v_dict == NULL) {
-      emsg(_(e_dictreq));
+    if (tv_check_for_nonnull_dict_arg(argvars, 2) == FAIL) {
       return;
     }
 
diff --git a/src/nvim/sign.c b/src/nvim/sign.c
index 50a55ddd5c..0e49a1e441 100644
--- a/src/nvim/sign.c
+++ b/src/nvim/sign.c
@@ -2017,8 +2017,7 @@ void f_sign_define(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
     return;
   }
 
-  if (argvars[1].v_type != VAR_UNKNOWN && argvars[1].v_type != VAR_DICT) {
-    emsg(_(e_dictreq));
+  if (tv_check_for_opt_dict_arg(argvars, 1) == FAIL) {
     return;
   }
 
@@ -2061,12 +2060,10 @@ void f_sign_getplaced(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
     }
 
     if (argvars[1].v_type != VAR_UNKNOWN) {
-      dict_T *dict;
-      if (argvars[1].v_type != VAR_DICT
-          || ((dict = argvars[1].vval.v_dict) == NULL)) {
-        emsg(_(e_dictreq));
+      if (tv_check_for_nonnull_dict_arg(argvars, 1) == FAIL) {
         return;
       }
+      dict_T *dict = argvars[1].vval.v_dict;
       if ((di = tv_dict_find(dict, "lnum", -1)) != NULL) {
         // get signs placed at this line
         lnum = (linenr_T)tv_get_number_chk(&di->di_tv, &notanum);
@@ -2263,11 +2260,11 @@ void f_sign_place(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 
   rettv->vval.v_number = -1;
 
-  if (argvars[4].v_type != VAR_UNKNOWN
-      && (argvars[4].v_type != VAR_DICT
-          || ((dict = argvars[4].vval.v_dict) == NULL))) {
-    emsg(_(e_dictreq));
-    return;
+  if (argvars[4].v_type != VAR_UNKNOWN) {
+    if (tv_check_for_nonnull_dict_arg(argvars, 4) == FAIL) {
+      return;
+    }
+    dict = argvars[4].vval.v_dict;
   }
 
   rettv->vval.v_number = sign_place_from_dict(&argvars[0], &argvars[1], &argvars[2], &argvars[3],
@@ -2415,8 +2412,7 @@ void f_sign_unplace(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   }
 
   if (argvars[1].v_type != VAR_UNKNOWN) {
-    if (argvars[1].v_type != VAR_DICT) {
-      emsg(_(e_dictreq));
+    if (tv_check_for_dict_arg(argvars, 1) == FAIL) {
       return;
     }
     dict = argvars[1].vval.v_dict;