vim-patch:8.1.0218: cannot add matches to another window

Problem:    Cannot add matches to another window. (Qiming Zhao)
Solution:   Add the "window" argument to matchadd() and matchaddpos().
            (closes vim/vim#3260)

95e51470f1

runtime/doc/eval.txt

@@ -5554,7 +5554,7 @@ match({expr}, {pat} [, {start} [, {count}]])			*match()*
 		the pattern.  'smartcase' is NOT used.	The matching is always
 		done like 'magic' is set and 'cpoptions' is empty.
 
-					*matchadd()* *E798* *E799* *E801*
+				*matchadd()* *E798* *E799* *E801* *E957*
 matchadd({group}, {pattern}[, {priority}[, {id} [, {dict}]]])
 		Defines a pattern to be highlighted in the current window (a
 		"match").  It will be highlighted with {group}.  Returns an
@@ -5593,6 +5593,8 @@ matchadd({group}, {pattern}[, {priority}[, {id} [, {dict}]]])
 			conceal	    Special character to show instead of the
 				    match (only for |hl-Conceal| highlighed
 				    matches, see |:syn-cchar|)
+			window	    Instead of the current window use the
+				    window with this number or window ID.
 
 		The number of matches is not limited, as it is the case with
 		the |:match| commands.

src/nvim/eval.c

@@ -12528,6 +12528,31 @@ static void f_match(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   find_some_match(argvars, rettv, kSomeMatch);
 }
 
+static int matchadd_dict_arg(typval_T *tv, const char **conceal_char,
+                             win_T **win)
+{
+  dictitem_T *di;
+
+  if (tv->v_type != VAR_DICT) {
+    EMSG(_(e_dictreq));
+    return FAIL;
+  }
+
+  if ((di = tv_dict_find(tv->vval.v_dict, S_LEN("conceal"))) != NULL) {
+    *conceal_char = tv_get_string(&di->di_tv);
+  }
+
+  if ((di = tv_dict_find(tv->vval.v_dict, S_LEN("window"))) != NULL) {
+    *win = find_win_by_nr(&di->di_tv, NULL);
+    if (*win == NULL) {
+      EMSG(_("E957: Invalid window number"));
+      return FAIL;
+    }
+  }
+
+  return OK;
+}
+
 /*
  * "matchadd()" function
  */
@@ -12541,6 +12566,7 @@ static void f_matchadd(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   int id = -1;
   bool error = false;
   const char *conceal_char = NULL;
+  win_T *win = curwin;
 
   rettv->vval.v_number = -1;
 
@@ -12551,16 +12577,9 @@ static void f_matchadd(typval_T *argvars, typval_T *rettv, FunPtr fptr)
     prio = tv_get_number_chk(&argvars[2], &error);
     if (argvars[3].v_type != VAR_UNKNOWN) {
       id = tv_get_number_chk(&argvars[3], &error);
-      if (argvars[4].v_type != VAR_UNKNOWN) {
-        if (argvars[4].v_type != VAR_DICT) {
-          EMSG(_(e_dictreq));
-          return;
-        }
-        dictitem_T *di;
-        if ((di = tv_dict_find(argvars[4].vval.v_dict, S_LEN("conceal")))
-            != NULL) {
-          conceal_char = tv_get_string(&di->di_tv);
-        }
+      if (argvars[4].v_type != VAR_UNKNOWN
+          && matchadd_dict_arg(&argvars[4], &conceal_char, &win) == FAIL) {
+        return;
       }
     }
   }
@@ -12572,8 +12591,7 @@ static void f_matchadd(typval_T *argvars, typval_T *rettv, FunPtr fptr)
     return;
   }
 
-  rettv->vval.v_number = match_add(curwin, grp, pat, prio, id, NULL,
-                                   conceal_char);
+  rettv->vval.v_number = match_add(win, grp, pat, prio, id, NULL, conceal_char);
 }
 
 static void f_matchaddpos(typval_T *argvars, typval_T *rettv, FunPtr fptr)
@@ -12601,21 +12619,15 @@ static void f_matchaddpos(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   int prio = 10;
   int id = -1;
   const char *conceal_char = NULL;
+  win_T *win = curwin;
 
   if (argvars[2].v_type != VAR_UNKNOWN) {
     prio = tv_get_number_chk(&argvars[2], &error);
     if (argvars[3].v_type != VAR_UNKNOWN) {
       id = tv_get_number_chk(&argvars[3], &error);
-      if (argvars[4].v_type != VAR_UNKNOWN) {
-        if (argvars[4].v_type != VAR_DICT) {
-          EMSG(_(e_dictreq));
-          return;
-        }
-        dictitem_T *di;
-        if ((di = tv_dict_find(argvars[4].vval.v_dict, S_LEN("conceal")))
-            != NULL) {
-          conceal_char = tv_get_string(&di->di_tv);
-        }
+      if (argvars[4].v_type != VAR_UNKNOWN
+          && matchadd_dict_arg(&argvars[4], &conceal_char, &win) == FAIL) {
+        return;
       }
     }
   }
@@ -12629,8 +12641,7 @@ static void f_matchaddpos(typval_T *argvars, typval_T *rettv, FunPtr fptr)
     return;
   }
 
-  rettv->vval.v_number = match_add(curwin, group, NULL, prio, id, l,
-                                   conceal_char);
+  rettv->vval.v_number = match_add(win, group, NULL, prio, id, l, conceal_char);
 }
 
 /*

src/nvim/testdir/test_match.vim

@@ -202,6 +202,28 @@ func Test_matchaddpos()
   set hlsearch&
 endfunc
 
+func Test_matchaddpos_otherwin()
+  syntax on
+  new
+  call setline(1, ['12345', 'NP'])
+  let winid = win_getid()
+
+  wincmd w
+  call matchadd('Search', '4', 10, -1, {'window': winid})
+  call matchaddpos('Error', [[1,2], [2,2]], 10, -1, {'window': winid})
+  redraw!
+  call assert_notequal(screenattr(1,2), 0)
+  call assert_notequal(screenattr(1,4), 0)
+  call assert_notequal(screenattr(2,2), 0)
+  call assert_equal(screenattr(1,2), screenattr(2,2))
+  call assert_notequal(screenattr(1,2), screenattr(1,4))
+
+  wincmd w
+  bwipe!
+  call clearmatches()
+  syntax off
+endfunc
+
 func Test_matchaddpos_using_negative_priority()
   set hlsearch