1 files changed, 72 insertions, 1 deletions

diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 4d66e34a70..b7ae0d4dc1 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -10404,6 +10404,23 @@ static void f_gettabwinvar(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   getwinvar(argvars, rettv, 1);
 }
 
+// "gettagstack()" function
+static void f_gettagstack(typval_T *argvars, typval_T *rettv, FunPtr fptr)
+{
+    win_T        *wp = curwin;                  // default is current window
+
+    tv_dict_alloc_ret(rettv);
+
+    if (argvars[0].v_type != VAR_UNKNOWN) {
+        wp = find_win_by_nr_or_id(&argvars[0]);
+        if (wp == NULL) {
+          return;
+        }
+    }
+
+    get_tagstack(wp, rettv->vval.v_dict);
+}
+
 /// Returns information about a window as a dictionary.
 static dict_T *get_win_info(win_T *wp, int16_t tpnr, int16_t winnr)
 {
@@ -15198,6 +15215,60 @@ static void f_settabwinvar(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   setwinvar(argvars, rettv, 1);
 }
 
+// "settagstack()" function
+static void f_settagstack(typval_T *argvars, typval_T *rettv, FunPtr fptr)
+{
+    static char *e_invact2 = N_("E962: Invalid action: '%s'");
+    win_T       *wp;
+    dict_T      *d;
+    int         action = 'r';
+
+    rettv->vval.v_number = -1;
+
+    // first argument: window number or id
+    wp = find_win_by_nr_or_id(&argvars[0]);
+    if (wp == NULL) {
+      return;
+    }
+
+    // second argument: dict with items to set in the tag stack
+    if (argvars[1].v_type != VAR_DICT) {
+        EMSG(_(e_dictreq));
+        return;
+    }
+    d = argvars[1].vval.v_dict;
+    if (d == NULL) {
+      return;
+    }
+
+    // third argument: action - 'a' for append and 'r' for replace.
+    // default is to replace the stack.
+    if (argvars[2].v_type == VAR_UNKNOWN) {
+      action = 'r';
+    } else if (argvars[2].v_type == VAR_STRING) {
+        const char *actstr;
+        actstr = tv_get_string_chk(&argvars[2]);
+        if (actstr == NULL) {
+          return;
+        }
+        if ((*actstr == 'r' || *actstr == 'a') && actstr[1] == NUL) {
+          action = *actstr;
+        } else {
+            EMSG2(_(e_invact2), actstr);
+            return;
+        }
+    } else {
+        EMSG(_(e_stringreq));
+        return;
+    }
+
+    if (set_tagstack(wp, d, action) == OK) {
+      rettv->vval.v_number = 0;
+    } else {
+      EMSG(_(e_listreq));
+    }
+}
+
 /*
  * "setwinvar()" function
  */
@@ -18220,7 +18291,7 @@ pos_T *var2fpos(const typval_T *const tv, const int dollar_lnum,
  * Return FAIL when conversion is not possible, doesn't check the position for
  * validity.
  */
-static int list2fpos(typval_T *arg, pos_T *posp, int *fnump, colnr_T *curswantp)
+int list2fpos(typval_T *arg, pos_T *posp, int *fnump, colnr_T *curswantp)
 {
   list_T *l;
   long i = 0;