2 files changed, 22 insertions, 48 deletions

diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index 9cd178eaeb..3613a8f8bc 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -380,8 +380,6 @@ void nvim_buf_set_lines(uint64_t channel_id,
     }
   }
 
-  win_T *save_curwin = NULL;
-  tabpage_T *save_curtab = NULL;
   size_t new_len = replacement.size;
   size_t old_len = (size_t)(end - start);
   ptrdiff_t extra = 0;  // lines added to text, can be negative
@@ -397,8 +395,8 @@ void nvim_buf_set_lines(uint64_t channel_id,
   }
 
   try_start();
-  bufref_T save_curbuf = { NULL, 0, 0 };
-  switch_to_win_for_buf(buf, &save_curwin, &save_curtab, &save_curbuf);
+  aco_save_T aco;
+  aucmd_prepbuf(&aco, (buf_T *)buf);
 
   if (u_save((linenr_T)(start - 1), (linenr_T)end) == FAIL) {
     api_set_error(err, kErrorTypeException, "Failed to save undo information");
@@ -465,27 +463,21 @@ void nvim_buf_set_lines(uint64_t channel_id,
   // changed range, and move any in the remainder of the buffer.
   // Only adjust marks if we managed to switch to a window that holds
   // the buffer, otherwise line numbers will be invalid.
-  if (save_curbuf.br_buf == NULL) {
-    mark_adjust((linenr_T)start,
-                (linenr_T)(end - 1),
-                MAXLNUM,
-                (long)extra,
-                false);
-  }
+  mark_adjust((linenr_T)start,
+              (linenr_T)(end - 1),
+              MAXLNUM,
+              (long)extra,
+              false);
 
   changed_lines((linenr_T)start, 0, (linenr_T)end, (long)extra, true);
 
-  if (save_curbuf.br_buf == NULL) {
-    fix_cursor((linenr_T)start, (linenr_T)end, (linenr_T)extra);
-  }
-
 end:
   for (size_t i = 0; i < new_len; i++) {
     xfree(lines[i]);
   }
 
   xfree(lines);
-  restore_win_for_buf(save_curwin, save_curtab, &save_curbuf);
+  aucmd_restbuf(&aco);
   try_end(err);
 }
 
@@ -1109,28 +1101,6 @@ free_exit:
   return 0;
 }
 
-// Check if deleting lines made the cursor position invalid.
-// Changed the lines from "lo" to "hi" and added "extra" lines (negative if
-// deleted).
-static void fix_cursor(linenr_T lo, linenr_T hi, linenr_T extra)
-{
-  if (curwin->w_cursor.lnum >= lo) {
-    // Adjust the cursor position if it's in/after the changed
-    // lines.
-    if (curwin->w_cursor.lnum >= hi) {
-      curwin->w_cursor.lnum += extra;
-      check_cursor_col();
-    } else if (extra < 0) {
-      curwin->w_cursor.lnum = lo;
-      check_cursor();
-    } else {
-      check_cursor_col();
-    }
-    changed_cline_bef_curs();
-  }
-  invalidate_botline();
-}
-
 // Normalizes 0-based indexes to buffer line numbers
 static int64_t normalize_index(buf_T *buf, int64_t index, bool *oob)
 {
diff --git a/src/nvim/api/vim.c b/src/nvim/api/vim.c
index 94d1697083..a773234ea0 100644
--- a/src/nvim/api/vim.c
+++ b/src/nvim/api/vim.c
@@ -15,6 +15,7 @@
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/dispatch.h"
 #include "nvim/api/buffer.h"
+#include "nvim/api/window.h"
 #include "nvim/msgpack_rpc/channel.h"
 #include "nvim/msgpack_rpc/helpers.h"
 #include "nvim/lua/executor.h"
@@ -31,6 +32,7 @@
 #include "nvim/edit.h"
 #include "nvim/eval.h"
 #include "nvim/eval/typval.h"
+#include "nvim/fileio.h"
 #include "nvim/option.h"
 #include "nvim/state.h"
 #include "nvim/syntax.h"
@@ -978,11 +980,12 @@ Buffer nvim_create_buf(Boolean listed, Boolean scratch, Error *err)
     return 0;
   }
   if (scratch) {
-    WITH_BUFFER(buf, {
-      set_option_value("bh", 0L, "hide", OPT_LOCAL);
-      set_option_value("bt", 0L, "nofile", OPT_LOCAL);
-      set_option_value("swf", 0L, NULL, OPT_LOCAL);
-    });
+    aco_save_T aco;
+    aucmd_prepbuf(&aco, buf);
+    set_option_value("bh", 0L, "hide", OPT_LOCAL);
+    set_option_value("bt", 0L, "nofile", OPT_LOCAL);
+    set_option_value("swf", 0L, NULL, OPT_LOCAL);
+    aucmd_restbuf(&aco);
   }
   return buf->b_fnum;
 }
@@ -995,6 +998,8 @@ Buffer nvim_create_buf(Boolean listed, Boolean scratch, Error *err)
 /// GUI with the |ui-multigrid| extension. External windows are only supported
 /// with multigrid GUIs, and are displayed as separate top-level windows.
 ///
+/// For a general overview of floats, see |api-floatwin|.
+///
 /// Exactly one of `external` and `relative` must be specified.
 ///
 /// @param buffer handle of buffer to be displayed in the window
@@ -1047,7 +1052,6 @@ Window nvim_open_win(Buffer buffer, Boolean enter,
                      Dictionary options, Error *err)
   FUNC_API_SINCE(6)
 {
-  win_T *old = curwin;
   FloatConfig config = FLOAT_CONFIG_INIT;
   if (!parse_float_config(options, &config, false, err)) {
     return 0;
@@ -1056,11 +1060,11 @@ Window nvim_open_win(Buffer buffer, Boolean enter,
   if (!wp) {
     return 0;
   }
-  if (buffer > 0) {
-    nvim_set_current_buf(buffer, err);
+  if (enter) {
+    win_enter(wp, false);
   }
-  if (!enter) {
-    win_enter(old, false);
+  if (buffer > 0) {
+    nvim_win_set_buf(wp->handle, buffer, err);
   }
   return wp->handle;
 }