refactor(api): always use TRY_WRAP #31600

Problem:  Two separate try/end wrappers, that only marginally differ by
          restoring a few variables. Wrappers that don't restore
          previous state are dangerous to use in "api-fast" functions.
Solution: Remove wrappers that don't restore the previous state.
          Always use TRY_WRAP.

10 files changed, 359 insertions, 409 deletions

diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index 9480292d9a..2b6aa8b371 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -360,93 +360,91 @@ void nvim_buf_set_lines(uint64_t channel_id, Buffer buffer, Integer start, Integ
     memchrsub(lines[i], NUL, NL, l.size);
   }
 
-  try_start();
-
-  if (!MODIFIABLE(buf)) {
-    api_set_error(err, kErrorTypeException, "Buffer is not 'modifiable'");
-    goto end;
-  }
-
-  if (u_save_buf(buf, (linenr_T)(start - 1), (linenr_T)end) == FAIL) {
-    api_set_error(err, kErrorTypeException, "Failed to save undo information");
-    goto end;
-  }
-
-  bcount_t deleted_bytes = get_region_bytecount(buf, (linenr_T)start, (linenr_T)end, 0, 0);
-
-  // If the size of the range is reducing (ie, new_len < old_len) we
-  // need to delete some old_len. We do this at the start, by
-  // repeatedly deleting line "start".
-  size_t to_delete = (new_len < old_len) ? old_len - new_len : 0;
-  for (size_t i = 0; i < to_delete; i++) {
-    if (ml_delete_buf(buf, (linenr_T)start, false) == FAIL) {
-      api_set_error(err, kErrorTypeException, "Failed to delete line");
+  TRY_WRAP(err, {
+    if (!MODIFIABLE(buf)) {
+      api_set_error(err, kErrorTypeException, "Buffer is not 'modifiable'");
       goto end;
     }
-  }
 
-  if (to_delete > 0) {
-    extra -= (ptrdiff_t)to_delete;
-  }
+    if (u_save_buf(buf, (linenr_T)(start - 1), (linenr_T)end) == FAIL) {
+      api_set_error(err, kErrorTypeException, "Failed to save undo information");
+      goto end;
+    }
 
-  // For as long as possible, replace the existing old_len with the
-  // new old_len. This is a more efficient operation, as it requires
-  // less memory allocation and freeing.
-  size_t to_replace = old_len < new_len ? old_len : new_len;
-  bcount_t inserted_bytes = 0;
-  for (size_t i = 0; i < to_replace; i++) {
-    int64_t lnum = start + (int64_t)i;
+    bcount_t deleted_bytes = get_region_bytecount(buf, (linenr_T)start, (linenr_T)end, 0, 0);
 
-    VALIDATE(lnum < MAXLNUM, "%s", "Index out of bounds", {
-      goto end;
-    });
+    // If the size of the range is reducing (ie, new_len < old_len) we
+    // need to delete some old_len. We do this at the start, by
+    // repeatedly deleting line "start".
+    size_t to_delete = (new_len < old_len) ? old_len - new_len : 0;
+    for (size_t i = 0; i < to_delete; i++) {
+      if (ml_delete_buf(buf, (linenr_T)start, false) == FAIL) {
+        api_set_error(err, kErrorTypeException, "Failed to delete line");
+        goto end;
+      }
+    }
 
-    if (ml_replace_buf(buf, (linenr_T)lnum, lines[i], false, true) == FAIL) {
-      api_set_error(err, kErrorTypeException, "Failed to replace line");
-      goto end;
+    if (to_delete > 0) {
+      extra -= (ptrdiff_t)to_delete;
     }
 
-    inserted_bytes += (bcount_t)strlen(lines[i]) + 1;
-  }
+    // For as long as possible, replace the existing old_len with the
+    // new old_len. This is a more efficient operation, as it requires
+    // less memory allocation and freeing.
+    size_t to_replace = old_len < new_len ? old_len : new_len;
+    bcount_t inserted_bytes = 0;
+    for (size_t i = 0; i < to_replace; i++) {
+      int64_t lnum = start + (int64_t)i;
+
+      VALIDATE(lnum < MAXLNUM, "%s", "Index out of bounds", {
+        goto end;
+      });
+
+      if (ml_replace_buf(buf, (linenr_T)lnum, lines[i], false, true) == FAIL) {
+        api_set_error(err, kErrorTypeException, "Failed to replace line");
+        goto end;
+      }
 
-  // Now we may need to insert the remaining new old_len
-  for (size_t i = to_replace; i < new_len; i++) {
-    int64_t lnum = start + (int64_t)i - 1;
+      inserted_bytes += (bcount_t)strlen(lines[i]) + 1;
+    }
 
-    VALIDATE(lnum < MAXLNUM, "%s", "Index out of bounds", {
-      goto end;
-    });
+    // Now we may need to insert the remaining new old_len
+    for (size_t i = to_replace; i < new_len; i++) {
+      int64_t lnum = start + (int64_t)i - 1;
 
-    if (ml_append_buf(buf, (linenr_T)lnum, lines[i], 0, false) == FAIL) {
-      api_set_error(err, kErrorTypeException, "Failed to insert line");
-      goto end;
-    }
+      VALIDATE(lnum < MAXLNUM, "%s", "Index out of bounds", {
+        goto end;
+      });
 
-    inserted_bytes += (bcount_t)strlen(lines[i]) + 1;
+      if (ml_append_buf(buf, (linenr_T)lnum, lines[i], 0, false) == FAIL) {
+        api_set_error(err, kErrorTypeException, "Failed to insert line");
+        goto end;
+      }
 
-    extra++;
-  }
+      inserted_bytes += (bcount_t)strlen(lines[i]) + 1;
 
-  // Adjust marks. Invalidate any which lie in the
-  // changed range, and move any in the remainder of the buffer.
-  linenr_T adjust = end > start ? MAXLNUM : 0;
-  mark_adjust_buf(buf, (linenr_T)start, (linenr_T)(end - 1), adjust, (linenr_T)extra,
-                  true, true, kExtmarkNOOP);
+      extra++;
+    }
 
-  extmark_splice(buf, (int)start - 1, 0, (int)(end - start), 0,
-                 deleted_bytes, (int)new_len, 0, inserted_bytes,
-                 kExtmarkUndo);
+    // Adjust marks. Invalidate any which lie in the
+    // changed range, and move any in the remainder of the buffer.
+    linenr_T adjust = end > start ? MAXLNUM : 0;
+    mark_adjust_buf(buf, (linenr_T)start, (linenr_T)(end - 1), adjust, (linenr_T)extra,
+                    true, true, kExtmarkNOOP);
 
-  changed_lines(buf, (linenr_T)start, 0, (linenr_T)end, (linenr_T)extra, true);
+    extmark_splice(buf, (int)start - 1, 0, (int)(end - start), 0,
+                   deleted_bytes, (int)new_len, 0, inserted_bytes,
+                   kExtmarkUndo);
 
-  FOR_ALL_TAB_WINDOWS(tp, win) {
-    if (win->w_buffer == buf) {
-      fix_cursor(win, (linenr_T)start, (linenr_T)end, (linenr_T)extra);
-    }
-  }
+    changed_lines(buf, (linenr_T)start, 0, (linenr_T)end, (linenr_T)extra, true);
 
-end:
-  try_end(err);
+    FOR_ALL_TAB_WINDOWS(tp, win) {
+      if (win->w_buffer == buf) {
+        fix_cursor(win, (linenr_T)start, (linenr_T)end, (linenr_T)extra);
+      }
+    }
+    end:;
+  });
 }
 
 /// Sets (replaces) a range in the buffer
@@ -593,101 +591,99 @@ void nvim_buf_set_text(uint64_t channel_id, Buffer buffer, Integer start_row, In
     new_byte += (bcount_t)(last_item.size) + 1;
   }
 
-  try_start();
-
-  if (!MODIFIABLE(buf)) {
-    api_set_error(err, kErrorTypeException, "Buffer is not 'modifiable'");
-    goto end;
-  }
-
-  // Small note about undo states: unlike set_lines, we want to save the
-  // undo state of one past the end_row, since end_row is inclusive.
-  if (u_save_buf(buf, (linenr_T)start_row - 1, (linenr_T)end_row + 1) == FAIL) {
-    api_set_error(err, kErrorTypeException, "Failed to save undo information");
-    goto end;
-  }
-
-  ptrdiff_t extra = 0;  // lines added to text, can be negative
-  size_t old_len = (size_t)(end_row - start_row + 1);
-
-  // If the size of the range is reducing (ie, new_len < old_len) we
-  // need to delete some old_len. We do this at the start, by
-  // repeatedly deleting line "start".
-  size_t to_delete = (new_len < old_len) ? old_len - new_len : 0;
-  for (size_t i = 0; i < to_delete; i++) {
-    if (ml_delete_buf(buf, (linenr_T)start_row, false) == FAIL) {
-      api_set_error(err, kErrorTypeException, "Failed to delete line");
+  TRY_WRAP(err, {
+    if (!MODIFIABLE(buf)) {
+      api_set_error(err, kErrorTypeException, "Buffer is not 'modifiable'");
       goto end;
     }
-  }
 
-  if (to_delete > 0) {
-    extra -= (ptrdiff_t)to_delete;
-  }
-
-  // For as long as possible, replace the existing old_len with the
-  // new old_len. This is a more efficient operation, as it requires
-  // less memory allocation and freeing.
-  size_t to_replace = old_len < new_len ? old_len : new_len;
-  for (size_t i = 0; i < to_replace; i++) {
-    int64_t lnum = start_row + (int64_t)i;
-
-    VALIDATE((lnum < MAXLNUM), "%s", "Index out of bounds", {
+    // Small note about undo states: unlike set_lines, we want to save the
+    // undo state of one past the end_row, since end_row is inclusive.
+    if (u_save_buf(buf, (linenr_T)start_row - 1, (linenr_T)end_row + 1) == FAIL) {
+      api_set_error(err, kErrorTypeException, "Failed to save undo information");
       goto end;
-    });
+    }
 
-    if (ml_replace_buf(buf, (linenr_T)lnum, lines[i], false, true) == FAIL) {
-      api_set_error(err, kErrorTypeException, "Failed to replace line");
-      goto end;
+    ptrdiff_t extra = 0;  // lines added to text, can be negative
+    size_t old_len = (size_t)(end_row - start_row + 1);
+
+    // If the size of the range is reducing (ie, new_len < old_len) we
+    // need to delete some old_len. We do this at the start, by
+    // repeatedly deleting line "start".
+    size_t to_delete = (new_len < old_len) ? old_len - new_len : 0;
+    for (size_t i = 0; i < to_delete; i++) {
+      if (ml_delete_buf(buf, (linenr_T)start_row, false) == FAIL) {
+        api_set_error(err, kErrorTypeException, "Failed to delete line");
+        goto end;
+      }
     }
-  }
 
-  // Now we may need to insert the remaining new old_len
-  for (size_t i = to_replace; i < new_len; i++) {
-    int64_t lnum = start_row + (int64_t)i - 1;
+    if (to_delete > 0) {
+      extra -= (ptrdiff_t)to_delete;
+    }
 
-    VALIDATE((lnum < MAXLNUM), "%s", "Index out of bounds", {
-      goto end;
-    });
+    // For as long as possible, replace the existing old_len with the
+    // new old_len. This is a more efficient operation, as it requires
+    // less memory allocation and freeing.
+    size_t to_replace = old_len < new_len ? old_len : new_len;
+    for (size_t i = 0; i < to_replace; i++) {
+      int64_t lnum = start_row + (int64_t)i;
 
-    if (ml_append_buf(buf, (linenr_T)lnum, lines[i], 0, false) == FAIL) {
-      api_set_error(err, kErrorTypeException, "Failed to insert line");
-      goto end;
+      VALIDATE((lnum < MAXLNUM), "%s", "Index out of bounds", {
+        goto end;
+      });
+
+      if (ml_replace_buf(buf, (linenr_T)lnum, lines[i], false, true) == FAIL) {
+        api_set_error(err, kErrorTypeException, "Failed to replace line");
+        goto end;
+      }
     }
 
-    extra++;
-  }
+    // Now we may need to insert the remaining new old_len
+    for (size_t i = to_replace; i < new_len; i++) {
+      int64_t lnum = start_row + (int64_t)i - 1;
 
-  colnr_T col_extent = (colnr_T)(end_col
-                                 - ((end_row == start_row) ? start_col : 0));
-
-  // Adjust marks. Invalidate any which lie in the
-  // changed range, and move any in the remainder of the buffer.
-  // Do not adjust any cursors. need to use column-aware logic (below)
-  linenr_T adjust = end_row >= start_row ? MAXLNUM : 0;
-  mark_adjust_buf(buf, (linenr_T)start_row, (linenr_T)end_row, adjust, (linenr_T)extra,
-                  true, true, kExtmarkNOOP);
-
-  extmark_splice(buf, (int)start_row - 1, (colnr_T)start_col,
-                 (int)(end_row - start_row), col_extent, old_byte,
-                 (int)new_len - 1, (colnr_T)last_item.size, new_byte,
-                 kExtmarkUndo);
-
-  changed_lines(buf, (linenr_T)start_row, 0, (linenr_T)end_row + 1, (linenr_T)extra, true);
-
-  FOR_ALL_TAB_WINDOWS(tp, win) {
-    if (win->w_buffer == buf) {
-      if (win->w_cursor.lnum >= start_row && win->w_cursor.lnum <= end_row) {
-        fix_cursor_cols(win, (linenr_T)start_row, (colnr_T)start_col, (linenr_T)end_row,
-                        (colnr_T)end_col, (linenr_T)new_len, (colnr_T)last_item.size);
-      } else {
-        fix_cursor(win, (linenr_T)start_row, (linenr_T)end_row, (linenr_T)extra);
+      VALIDATE((lnum < MAXLNUM), "%s", "Index out of bounds", {
+        goto end;
+      });
+
+      if (ml_append_buf(buf, (linenr_T)lnum, lines[i], 0, false) == FAIL) {
+        api_set_error(err, kErrorTypeException, "Failed to insert line");
+        goto end;
       }
+
+      extra++;
     }
-  }
 
-end:
-  try_end(err);
+    colnr_T col_extent = (colnr_T)(end_col
+                                   - ((end_row == start_row) ? start_col : 0));
+
+    // Adjust marks. Invalidate any which lie in the
+    // changed range, and move any in the remainder of the buffer.
+    // Do not adjust any cursors. need to use column-aware logic (below)
+    linenr_T adjust = end_row >= start_row ? MAXLNUM : 0;
+    mark_adjust_buf(buf, (linenr_T)start_row, (linenr_T)end_row, adjust, (linenr_T)extra,
+                    true, true, kExtmarkNOOP);
+
+    extmark_splice(buf, (int)start_row - 1, (colnr_T)start_col,
+                   (int)(end_row - start_row), col_extent, old_byte,
+                   (int)new_len - 1, (colnr_T)last_item.size, new_byte,
+                   kExtmarkUndo);
+
+    changed_lines(buf, (linenr_T)start_row, 0, (linenr_T)end_row + 1, (linenr_T)extra, true);
+
+    FOR_ALL_TAB_WINDOWS(tp, win) {
+      if (win->w_buffer == buf) {
+        if (win->w_cursor.lnum >= start_row && win->w_cursor.lnum <= end_row) {
+          fix_cursor_cols(win, (linenr_T)start_row, (colnr_T)start_col, (linenr_T)end_row,
+                          (colnr_T)end_col, (linenr_T)new_len, (colnr_T)last_item.size);
+        } else {
+          fix_cursor(win, (linenr_T)start_row, (linenr_T)end_row, (linenr_T)extra);
+        }
+      }
+    }
+    end:;
+  });
 }
 
 /// Gets a range from the buffer.
@@ -965,26 +961,27 @@ void nvim_buf_set_name(Buffer buffer, String name, Error *err)
     return;
   }
 
-  try_start();
-
-  const bool is_curbuf = buf == curbuf;
-  const int save_acd = p_acd;
-  if (!is_curbuf) {
-    // Temporarily disable 'autochdir' when setting file name for another buffer.
-    p_acd = false;
-  }
+  int ren_ret = OK;
+  TRY_WRAP(err, {
+    const bool is_curbuf = buf == curbuf;
+    const int save_acd = p_acd;
+    if (!is_curbuf) {
+      // Temporarily disable 'autochdir' when setting file name for another buffer.
+      p_acd = false;
+    }
 
-  // Using aucmd_*: autocommands will be executed by rename_buffer
-  aco_save_T aco;
-  aucmd_prepbuf(&aco, buf);
-  int ren_ret = rename_buffer(name.data);
-  aucmd_restbuf(&aco);
+    // Using aucmd_*: autocommands will be executed by rename_buffer
+    aco_save_T aco;
+    aucmd_prepbuf(&aco, buf);
+    ren_ret = rename_buffer(name.data);
+    aucmd_restbuf(&aco);
 
-  if (!is_curbuf) {
-    p_acd = save_acd;
-  }
+    if (!is_curbuf) {
+      p_acd = save_acd;
+    }
+  });
 
-  if (try_end(err)) {
+  if (ERROR_SET(err)) {
     return;
   }
 
@@ -1204,15 +1201,18 @@ Object nvim_buf_call(Buffer buffer, LuaRef fun, Error *err)
   if (!buf) {
     return NIL;
   }
-  try_start();
-  aco_save_T aco;
-  aucmd_prepbuf(&aco, buf);
 
-  Array args = ARRAY_DICT_INIT;
-  Object res = nlua_call_ref(fun, NULL, args, kRetLuaref, NULL, err);
+  Object res = OBJECT_INIT;
+  TRY_WRAP(err, {
+    aco_save_T aco;
+    aucmd_prepbuf(&aco, buf);
+
+    Array args = ARRAY_DICT_INIT;
+    res = nlua_call_ref(fun, NULL, args, kRetLuaref, NULL, err);
+
+    aucmd_restbuf(&aco);
+  });
 
-  aucmd_restbuf(&aco);
-  try_end(err);
   return res;
 }
 
diff --git a/src/nvim/api/private/helpers.c b/src/nvim/api/private/helpers.c
index 5bf66a092f..4389ae3b35 100644
--- a/src/nvim/api/private/helpers.c
+++ b/src/nvim/api/private/helpers.c
@@ -42,8 +42,10 @@
 
 /// Start block that may cause Vimscript exceptions while evaluating another code
 ///
-/// Used when caller is supposed to be operating when other Vimscript code is being
-/// processed and that “other Vimscript code” must not be affected.
+/// Used just in case caller is supposed to be operating when other Vimscript code
+/// is being processed and that “other Vimscript code” must not be affected.
+///
+/// @warning Avoid calling directly; use TRY_WRAP instead.
 ///
 /// @param[out]  tstate  Location where try state should be saved.
 void try_enter(TryState *const tstate)
@@ -55,75 +57,33 @@ void try_enter(TryState *const tstate)
     .current_exception = current_exception,
     .msg_list = (const msglist_T *const *)msg_list,
     .private_msg_list = NULL,
-    .trylevel = trylevel,
     .got_int = got_int,
     .did_throw = did_throw,
     .need_rethrow = need_rethrow,
     .did_emsg = did_emsg,
   };
+  // `msg_list` controls the collection of abort-causing non-exception errors,
+  // which would otherwise be ignored.  This pattern is from do_cmdline().
   msg_list = &tstate->private_msg_list;
   current_exception = NULL;
-  trylevel = 1;
   got_int = false;
   did_throw = false;
   need_rethrow = false;
   did_emsg = false;
-}
-
-/// End try block, set the error message if any and restore previous state
-///
-/// @warning Return is consistent with most functions (false on error), not with
-///          try_end (true on error).
-///
-/// @param[in]  tstate  Previous state to restore.
-/// @param[out]  err  Location where error should be saved.
-///
-/// @return false if error occurred, true otherwise.
-bool try_leave(const TryState *const tstate, Error *const err)
-  FUNC_ATTR_NONNULL_ALL FUNC_ATTR_WARN_UNUSED_RESULT
-{
-  const bool ret = !try_end(err);
-  assert(trylevel == 0);
-  assert(!need_rethrow);
-  assert(!got_int);
-  assert(!did_throw);
-  assert(!did_emsg);
-  assert(msg_list == &tstate->private_msg_list);
-  assert(*msg_list == NULL);
-  assert(current_exception == NULL);
-  msg_list = (msglist_T **)tstate->msg_list;
-  current_exception = tstate->current_exception;
-  trylevel = tstate->trylevel;
-  got_int = tstate->got_int;
-  did_throw = tstate->did_throw;
-  need_rethrow = tstate->need_rethrow;
-  did_emsg = tstate->did_emsg;
-  return ret;
-}
-
-/// Starts a block that may cause Vimscript exceptions; must be mirrored by `try_end()` call.
-///
-/// Note: use `TRY_WRAP` instead (except in `FUNC_API_FAST` functions such as nvim_get_runtime_file).
-///
-/// To be used as a replacement of `:try … catch … endtry` in C code, in cases
-/// when error flag could not already be set. If there may be pending error
-/// state at the time try_start() is executed which needs to be preserved,
-/// try_enter()/try_leave() pair should be used instead.
-void try_start(void)
-{
   trylevel++;
 }
 
-/// Ends a `try_start` block; sets error message if any and returns true if an error occurred.
+/// Ends a `try_enter` block; sets error message if any.
 ///
-/// Note: use `TRY_WRAP` instead (except in `FUNC_API_FAST` functions such as nvim_get_runtime_file).
+/// @warning Avoid calling directly; use TRY_WRAP instead.
 ///
-/// @param err Pointer to the stack-allocated error object
-/// @return true if an error occurred
-bool try_end(Error *err)
+/// @param[out] err Pointer to the stack-allocated error object
+void try_leave(const TryState *const tstate, Error *const err)
+  FUNC_ATTR_NONNULL_ALL
 {
   // Note: all globals manipulated here should be saved/restored in
   // try_enter/try_leave.
+  assert(trylevel > 0);
   trylevel--;
 
   // Set by emsg(), affects aborting().  See also enter_cleanup().
@@ -166,7 +126,20 @@ bool try_end(Error *err)
     discard_current_exception();
   }
 
-  return ERROR_SET(err);
+  assert(msg_list == &tstate->private_msg_list);
+  assert(*msg_list == NULL);
+  assert(current_exception == NULL);
+  assert(!got_int);
+  assert(!did_throw);
+  assert(!need_rethrow);
+  assert(!did_emsg);
+  // Restore the exception context.
+  msg_list = (msglist_T **)tstate->msg_list;
+  current_exception = tstate->current_exception;
+  got_int = tstate->got_int;
+  did_throw = tstate->did_throw;
+  need_rethrow = tstate->need_rethrow;
+  did_emsg = tstate->did_emsg;
 }
 
 /// Recursively expands a vimscript value in a dict
diff --git a/src/nvim/api/private/helpers.h b/src/nvim/api/private/helpers.h
index d06f5c9c65..03ff811449 100644
--- a/src/nvim/api/private/helpers.h
+++ b/src/nvim/api/private/helpers.h
@@ -147,27 +147,19 @@ typedef struct {
   except_T *current_exception;
   msglist_T *private_msg_list;
   const msglist_T *const *msg_list;
-  int trylevel;
   int got_int;
   bool did_throw;
   int need_rethrow;
   int did_emsg;
 } TryState;
 
-// `msg_list` controls the collection of abort-causing non-exception errors,
-// which would otherwise be ignored.  This pattern is from do_cmdline().
-//
 // TODO(bfredl): prepare error-handling at "top level" (nv_event).
 #define TRY_WRAP(err, code) \
   do { \
-    msglist_T **saved_msg_list = msg_list; \
-    msglist_T *private_msg_list; \
-    msg_list = &private_msg_list; \
-    private_msg_list = NULL; \
-    try_start(); \
+    TryState tstate; \
+    try_enter(&tstate); \
     code; \
-    try_end(err); \
-    msg_list = saved_msg_list;  /* Restore the exception context. */ \
+    try_leave(&tstate, err); \
   } while (0)
 
 // Execute code with cursor position saved and restored and textlock active.
diff --git a/src/nvim/api/tabpage.c b/src/nvim/api/tabpage.c
index 56a3f1cf23..b4d519dc98 100644
--- a/src/nvim/api/tabpage.c
+++ b/src/nvim/api/tabpage.c
@@ -146,11 +146,9 @@ void nvim_tabpage_set_win(Tabpage tabpage, Window win, Error *err)
   }
 
   if (tp == curtab) {
-    try_start();
-    win_goto(wp);
-    if (!try_end(err) && curwin != wp) {
-      api_set_error(err, kErrorTypeException, "Failed to switch to window %d", win);
-    }
+    TRY_WRAP(err, {
+      win_goto(wp);
+    });
   } else if (tp->tp_curwin != wp) {
     tp->tp_prevwin = tp->tp_curwin;
     tp->tp_curwin = wp;
diff --git a/src/nvim/api/vim.c b/src/nvim/api/vim.c
index d82f90d1dd..fce7a86245 100644
--- a/src/nvim/api/vim.c
+++ b/src/nvim/api/vim.c
@@ -594,12 +594,10 @@ ArrayOf(String) nvim_get_runtime_file(String name, Boolean all, Arena *arena, Er
   kvi_init(cookie.rv);
 
   int flags = DIP_DIRFILE | (all ? DIP_ALL : 0);
-  TryState tstate;
 
-  // XXX: intentionally not using `TRY_WRAP`, to avoid `did_emsg=false` in `try_end`.
-  try_enter(&tstate);
-  do_in_runtimepath((name.size ? name.data : ""), flags, find_runtime_cb, &cookie);
-  vim_ignored = try_leave(&tstate, err);
+  TRY_WRAP(err, {
+    do_in_runtimepath((name.size ? name.data : ""), flags, find_runtime_cb, &cookie);
+  });
 
   return arena_take_arraybuilder(arena, &cookie.rv);
 }
@@ -952,68 +950,70 @@ void nvim_set_current_win(Window window, Error *err)
 Buffer nvim_create_buf(Boolean listed, Boolean scratch, Error *err)
   FUNC_API_SINCE(6)
 {
-  try_start();
-  // Block autocommands for now so they don't mess with the buffer before we
-  // finish configuring it.
-  block_autocmds();
-
-  buf_T *buf = buflist_new(NULL, NULL, 0,
-                           BLN_NOOPT | BLN_NEW | (listed ? BLN_LISTED : 0));
-  if (buf == NULL) {
-    unblock_autocmds();
-    goto fail;
-  }
+  Buffer ret = 0;
 
-  // Open the memline for the buffer. This will avoid spurious autocmds when
-  // a later nvim_buf_set_lines call would have needed to "open" the buffer.
-  if (ml_open(buf) == FAIL) {
-    unblock_autocmds();
-    goto fail;
-  }
-
-  // Set last_changedtick to avoid triggering a TextChanged autocommand right
-  // after it was added.
-  buf->b_last_changedtick = buf_get_changedtick(buf);
-  buf->b_last_changedtick_i = buf_get_changedtick(buf);
-  buf->b_last_changedtick_pum = buf_get_changedtick(buf);
+  TRY_WRAP(err, {
+    // Block autocommands for now so they don't mess with the buffer before we
+    // finish configuring it.
+    block_autocmds();
+
+    buf_T *buf = buflist_new(NULL, NULL, 0,
+                             BLN_NOOPT | BLN_NEW | (listed ? BLN_LISTED : 0));
+    if (buf == NULL) {
+      unblock_autocmds();
+      goto fail;
+    }
 
-  // Only strictly needed for scratch, but could just as well be consistent
-  // and do this now. Buffer is created NOW, not when it later first happens
-  // to reach a window or aucmd_prepbuf() ..
-  buf_copy_options(buf, BCO_ENTER | BCO_NOHELP);
+    // Open the memline for the buffer. This will avoid spurious autocmds when
+    // a later nvim_buf_set_lines call would have needed to "open" the buffer.
+    if (ml_open(buf) == FAIL) {
+      unblock_autocmds();
+      goto fail;
+    }
 
-  if (scratch) {
-    set_option_direct_for(kOptBufhidden, STATIC_CSTR_AS_OPTVAL("hide"), OPT_LOCAL, 0,
-                          kOptScopeBuf, buf);
-    set_option_direct_for(kOptBuftype, STATIC_CSTR_AS_OPTVAL("nofile"), OPT_LOCAL, 0,
-                          kOptScopeBuf, buf);
-    assert(buf->b_ml.ml_mfp->mf_fd < 0);  // ml_open() should not have opened swapfile already
-    buf->b_p_swf = false;
-    buf->b_p_ml = false;
-  }
+    // Set last_changedtick to avoid triggering a TextChanged autocommand right
+    // after it was added.
+    buf->b_last_changedtick = buf_get_changedtick(buf);
+    buf->b_last_changedtick_i = buf_get_changedtick(buf);
+    buf->b_last_changedtick_pum = buf_get_changedtick(buf);
+
+    // Only strictly needed for scratch, but could just as well be consistent
+    // and do this now. Buffer is created NOW, not when it later first happens
+    // to reach a window or aucmd_prepbuf() ..
+    buf_copy_options(buf, BCO_ENTER | BCO_NOHELP);
+
+    if (scratch) {
+      set_option_direct_for(kOptBufhidden, STATIC_CSTR_AS_OPTVAL("hide"), OPT_LOCAL, 0,
+                            kOptScopeBuf, buf);
+      set_option_direct_for(kOptBuftype, STATIC_CSTR_AS_OPTVAL("nofile"), OPT_LOCAL, 0,
+                            kOptScopeBuf, buf);
+      assert(buf->b_ml.ml_mfp->mf_fd < 0);  // ml_open() should not have opened swapfile already
+      buf->b_p_swf = false;
+      buf->b_p_ml = false;
+    }
 
-  unblock_autocmds();
+    unblock_autocmds();
 
-  bufref_T bufref;
-  set_bufref(&bufref, buf);
-  if (apply_autocmds(EVENT_BUFNEW, NULL, NULL, false, buf)
-      && !bufref_valid(&bufref)) {
-    goto fail;
-  }
-  if (listed
-      && apply_autocmds(EVENT_BUFADD, NULL, NULL, false, buf)
-      && !bufref_valid(&bufref)) {
-    goto fail;
-  }
+    bufref_T bufref;
+    set_bufref(&bufref, buf);
+    if (apply_autocmds(EVENT_BUFNEW, NULL, NULL, false, buf)
+        && !bufref_valid(&bufref)) {
+      goto fail;
+    }
+    if (listed
+        && apply_autocmds(EVENT_BUFADD, NULL, NULL, false, buf)
+        && !bufref_valid(&bufref)) {
+      goto fail;
+    }
 
-  try_end(err);
-  return buf->b_fnum;
+    ret = buf->b_fnum;
+    fail:;
+  });
 
-fail:
-  if (!try_end(err)) {
+  if (ret == 0 && !ERROR_SET(err)) {
     api_set_error(err, kErrorTypeException, "Failed to create buffer");
   }
-  return 0;
+  return ret;
 }
 
 /// Open a terminal instance in a buffer
diff --git a/src/nvim/api/vimscript.c b/src/nvim/api/vimscript.c
index 0ff2b037ce..67db615b20 100644
--- a/src/nvim/api/vimscript.c
+++ b/src/nvim/api/vimscript.c
@@ -78,24 +78,24 @@ String exec_impl(uint64_t channel_id, String src, Dict(exec_opts) *opts, Error *
     capture_ga = &capture_local;
   }
 
-  try_start();
-  if (opts->output) {
-    msg_silent++;
-    msg_col = 0;  // prevent leading spaces
-  }
+  TRY_WRAP(err, {
+    if (opts->output) {
+      msg_silent++;
+      msg_col = 0;  // prevent leading spaces
+    }
 
-  const sctx_T save_current_sctx = api_set_sctx(channel_id);
+    const sctx_T save_current_sctx = api_set_sctx(channel_id);
 
-  do_source_str(src.data, "nvim_exec2()");
-  if (opts->output) {
-    capture_ga = save_capture_ga;
-    msg_silent = save_msg_silent;
-    // Put msg_col back where it was, since nothing should have been written.
-    msg_col = save_msg_col;
-  }
+    do_source_str(src.data, "nvim_exec2()");
+    if (opts->output) {
+      capture_ga = save_capture_ga;
+      msg_silent = save_msg_silent;
+      // Put msg_col back where it was, since nothing should have been written.
+      msg_col = save_msg_col;
+    }
 
-  current_sctx = save_current_sctx;
-  try_end(err);
+    current_sctx = save_current_sctx;
+  });
 
   if (ERROR_SET(err)) {
     goto theend;
diff --git a/src/nvim/api/window.c b/src/nvim/api/window.c
index f5e8d8f086..387dad899e 100644
--- a/src/nvim/api/window.c
+++ b/src/nvim/api/window.c
@@ -368,19 +368,16 @@ void nvim_win_hide(Window window, Error *err)
   }
 
   tabpage_T *tabpage = win_find_tabpage(win);
-  TryState tstate;
-  try_enter(&tstate);
-
-  // Never close the autocommand window.
-  if (is_aucmd_win(win)) {
-    emsg(_(e_autocmd_close));
-  } else if (tabpage == curtab) {
-    win_close(win, false, false);
-  } else {
-    win_close_othertab(win, false, tabpage);
-  }
-
-  vim_ignored = try_leave(&tstate, err);
+  TRY_WRAP(err, {
+    // Never close the autocommand window.
+    if (is_aucmd_win(win)) {
+      emsg(_(e_autocmd_close));
+    } else if (tabpage == curtab) {
+      win_close(win, false, false);
+    } else {
+      win_close_othertab(win, false, tabpage);
+    }
+  });
 }
 
 /// Closes the window (like |:close| with a |window-ID|).
@@ -400,10 +397,9 @@ void nvim_win_close(Window window, Boolean force, Error *err)
   }
 
   tabpage_T *tabpage = win_find_tabpage(win);
-  TryState tstate;
-  try_enter(&tstate);
-  ex_win_close(force, win, tabpage == curtab ? NULL : tabpage);
-  vim_ignored = try_leave(&tstate, err);
+  TRY_WRAP(err, {
+    ex_win_close(force, win, tabpage == curtab ? NULL : tabpage);
+  });
 }
 
 /// Calls a function with window as temporary current window.
diff --git a/src/nvim/ex_getln.c b/src/nvim/ex_getln.c
index 85fbdbd20a..2c1653006c 100644
--- a/src/nvim/ex_getln.c
+++ b/src/nvim/ex_getln.c
@@ -787,9 +787,7 @@ static uint8_t *command_line_enter(int firstc, int count, int indent, bool clear
   setmouse();
   setcursor();
 
-  TryState tstate;
   Error err = ERROR_INIT;
-  bool tl_ret = true;
   char firstcbuf[2];
   firstcbuf[0] = (char)(firstc > 0 ? firstc : '-');
   firstcbuf[1] = 0;
@@ -802,20 +800,19 @@ static uint8_t *command_line_enter(int firstc, int count, int indent, bool clear
     tv_dict_add_str(dict, S_LEN("cmdtype"), firstcbuf);
     tv_dict_add_nr(dict, S_LEN("cmdlevel"), ccline.level);
     tv_dict_set_keys_readonly(dict);
-    try_enter(&tstate);
+    TRY_WRAP(&err, {
+      apply_autocmds(EVENT_CMDLINEENTER, firstcbuf, firstcbuf, false, curbuf);
+      restore_v_event(dict, &save_v_event);
+    });
 
-    apply_autocmds(EVENT_CMDLINEENTER, firstcbuf, firstcbuf, false, curbuf);
-    restore_v_event(dict, &save_v_event);
-
-    tl_ret = try_leave(&tstate, &err);
-    if (!tl_ret && ERROR_SET(&err)) {
+    if (ERROR_SET(&err)) {
       msg_putchar('\n');
       msg_scroll = true;
       msg_puts_hl(err.msg, HLF_E, true);
       api_clear_error(&err);
       redrawcmd();
     }
-    tl_ret = true;
+    err = ERROR_INIT;
   }
   may_trigger_modechanged();
 
@@ -873,10 +870,10 @@ static uint8_t *command_line_enter(int firstc, int count, int indent, bool clear
     // not readonly:
     tv_dict_add_bool(dict, S_LEN("abort"),
                      s->gotesc ? kBoolVarTrue : kBoolVarFalse);
-    try_enter(&tstate);
-    apply_autocmds(EVENT_CMDLINELEAVE, firstcbuf, firstcbuf, false, curbuf);
-    // error printed below, to avoid redraw issues
-    tl_ret = try_leave(&tstate, &err);
+    TRY_WRAP(&err, {
+      apply_autocmds(EVENT_CMDLINELEAVE, firstcbuf, firstcbuf, false, curbuf);
+      // error printed below, to avoid redraw issues
+    });
     if (tv_dict_get_number(dict, "abort") != 0) {
       s->gotesc = true;
     }
@@ -929,7 +926,7 @@ static uint8_t *command_line_enter(int firstc, int count, int indent, bool clear
   msg_scroll = s->save_msg_scroll;
   redir_off = false;
 
-  if (!tl_ret && ERROR_SET(&err)) {
+  if (ERROR_SET(&err)) {
     msg_putchar('\n');
     emsg(err.msg);
     did_emsg = false;
@@ -937,7 +934,7 @@ static uint8_t *command_line_enter(int firstc, int count, int indent, bool clear
   }
 
   // When the command line was typed, no need for a wait-return prompt.
-  if (s->some_key_typed && tl_ret) {
+  if (s->some_key_typed && !ERROR_SET(&err)) {
     need_wait_return = false;
   }
 
@@ -2315,11 +2312,13 @@ static win_T *cmdpreview_open_win(buf_T *cmdpreview_buf)
 
   win_T *preview_win = curwin;
   Error err = ERROR_INIT;
+  int result = OK;
 
   // Switch to preview buffer
-  try_start();
-  int result = do_buffer(DOBUF_GOTO, DOBUF_FIRST, FORWARD, cmdpreview_buf->handle, 0);
-  if (try_end(&err) || result == FAIL) {
+  TRY_WRAP(&err, {
+    result = do_buffer(DOBUF_GOTO, DOBUF_FIRST, FORWARD, cmdpreview_buf->handle, 0);
+  });
+  if (ERROR_SET(&err) || result == FAIL) {
     api_clear_error(&err);
     return NULL;
   }
@@ -2600,9 +2599,10 @@ static bool cmdpreview_may_show(CommandLineState *s)
   // open the preview window. The preview callback also handles doing the changes and highlights for
   // the preview.
   Error err = ERROR_INIT;
-  try_start();
-  cmdpreview_type = execute_cmd(&ea, &cmdinfo, true);
-  if (try_end(&err)) {
+  TRY_WRAP(&err, {
+    cmdpreview_type = execute_cmd(&ea, &cmdinfo, true);
+  });
+  if (ERROR_SET(&err)) {
     api_clear_error(&err);
     cmdpreview_type = 0;
   }
@@ -2643,7 +2643,6 @@ end:
 static void do_autocmd_cmdlinechanged(int firstc)
 {
   if (has_event(EVENT_CMDLINECHANGED)) {
-    TryState tstate;
     Error err = ERROR_INIT;
     save_v_event_T save_v_event;
     dict_T *dict = get_v_event(&save_v_event);
@@ -2656,13 +2655,11 @@ static void do_autocmd_cmdlinechanged(int firstc)
     tv_dict_add_str(dict, S_LEN("cmdtype"), firstcbuf);
     tv_dict_add_nr(dict, S_LEN("cmdlevel"), ccline.level);
     tv_dict_set_keys_readonly(dict);
-    try_enter(&tstate);
-
-    apply_autocmds(EVENT_CMDLINECHANGED, firstcbuf, firstcbuf, false, curbuf);
-    restore_v_event(dict, &save_v_event);
-
-    bool tl_ret = try_leave(&tstate, &err);
-    if (!tl_ret && ERROR_SET(&err)) {
+    TRY_WRAP(&err, {
+      apply_autocmds(EVENT_CMDLINECHANGED, firstcbuf, firstcbuf, false, curbuf);
+      restore_v_event(dict, &save_v_event);
+    });
+    if (ERROR_SET(&err)) {
       msg_putchar('\n');
       msg_scroll = true;
       msg_puts_hl(err.msg, HLF_E, true);
@@ -3179,11 +3176,9 @@ static bool color_cmdline(CmdlineInfo *colored_ccline)
   static int prev_prompt_errors = 0;
   Callback color_cb = CALLBACK_NONE;
   bool can_free_cb = false;
-  TryState tstate;
   Error err = ERROR_INIT;
   const char *err_errmsg = e_intern2;
   bool dgc_ret = true;
-  bool tl_ret = true;
 
   if (colored_ccline->prompt_id != prev_prompt_id) {
     prev_prompt_errors = 0;
@@ -3196,16 +3191,16 @@ static bool color_cmdline(CmdlineInfo *colored_ccline)
     assert(colored_ccline->input_fn);
     color_cb = colored_ccline->highlight_callback;
   } else if (colored_ccline->cmdfirstc == ':') {
-    try_enter(&tstate);
-    err_errmsg = N_("E5408: Unable to get g:Nvim_color_cmdline callback: %s");
-    dgc_ret = tv_dict_get_callback(&globvardict, S_LEN("Nvim_color_cmdline"),
-                                   &color_cb);
-    tl_ret = try_leave(&tstate, &err);
+    TRY_WRAP(&err, {
+      err_errmsg = N_("E5408: Unable to get g:Nvim_color_cmdline callback: %s");
+      dgc_ret = tv_dict_get_callback(&globvardict, S_LEN("Nvim_color_cmdline"),
+                                     &color_cb);
+    });
     can_free_cb = true;
   } else if (colored_ccline->cmdfirstc == '=') {
     color_expr_cmdline(colored_ccline, ccline_colors);
   }
-  if (!tl_ret || !dgc_ret) {
+  if (ERROR_SET(&err) || !dgc_ret) {
     goto color_cmdline_error;
   }
 
@@ -3226,20 +3221,22 @@ static bool color_cmdline(CmdlineInfo *colored_ccline)
   // correct, with msg_col it just misses leading `:`. Since `redraw!` in
   // callback lags this is least of the user problems.
   //
-  // Also using try_enter() because error messages may overwrite typed
+  // Also using TRY_WRAP because error messages may overwrite typed
   // command-line which is not expected.
   getln_interrupted_highlight = false;
-  try_enter(&tstate);
-  err_errmsg = N_("E5407: Callback has thrown an exception: %s");
-  const int saved_msg_col = msg_col;
-  msg_silent++;
-  const bool cbcall_ret = callback_call(&color_cb, 1, &arg, &tv);
-  msg_silent--;
-  msg_col = saved_msg_col;
-  if (got_int) {
-    getln_interrupted_highlight = true;
-  }
-  if (!try_leave(&tstate, &err) || !cbcall_ret) {
+  bool cbcall_ret = true;
+  TRY_WRAP(&err, {
+    err_errmsg = N_("E5407: Callback has thrown an exception: %s");
+    const int saved_msg_col = msg_col;
+    msg_silent++;
+    cbcall_ret = callback_call(&color_cb, 1, &arg, &tv);
+    msg_silent--;
+    msg_col = saved_msg_col;
+    if (got_int) {
+      getln_interrupted_highlight = true;
+    }
+  });
+  if (ERROR_SET(&err) || !cbcall_ret) {
     goto color_cmdline_error;
   }
   if (tv.v_type != VAR_LIST) {
diff --git a/src/nvim/lua/stdlib.c b/src/nvim/lua/stdlib.c
index 5ebff3a809..4de25f4265 100644
--- a/src/nvim/lua/stdlib.c
+++ b/src/nvim/lua/stdlib.c
@@ -623,38 +623,32 @@ static int nlua_with(lua_State *L)
   cmdmod.cmod_flags = flags;
   apply_cmdmod(&cmdmod);
 
-  if (buf || win) {
-    try_start();
-  }
-
-  aco_save_T aco;
-  win_execute_T win_execute_args;
   Error err = ERROR_INIT;
+  TRY_WRAP(&err, {
+    aco_save_T aco;
+    win_execute_T win_execute_args;
 
-  if (win) {
-    tabpage_T *tabpage = win_find_tabpage(win);
-    if (!win_execute_before(&win_execute_args, win, tabpage)) {
-      goto end;
+    if (win) {
+      tabpage_T *tabpage = win_find_tabpage(win);
+      if (!win_execute_before(&win_execute_args, win, tabpage)) {
+        goto end;
+      }
+    } else if (buf) {
+      aucmd_prepbuf(&aco, buf);
     }
-  } else if (buf) {
-    aucmd_prepbuf(&aco, buf);
-  }
 
-  int s = lua_gettop(L);
-  lua_pushvalue(L, 2);
-  status = lua_pcall(L, 0, LUA_MULTRET, 0);
-  rets = lua_gettop(L) - s;
+    int s = lua_gettop(L);
+    lua_pushvalue(L, 2);
+    status = lua_pcall(L, 0, LUA_MULTRET, 0);
+    rets = lua_gettop(L) - s;
 
-  if (win) {
-    win_execute_after(&win_execute_args);
-  } else if (buf) {
-    aucmd_restbuf(&aco);
-  }
-
-end:
-  if (buf || win) {
-    try_end(&err);
-  }
+    if (win) {
+      win_execute_after(&win_execute_args);
+    } else if (buf) {
+      aucmd_restbuf(&aco);
+    }
+    end:;
+  });
 
   undo_cmdmod(&cmdmod);
   cmdmod = save_cmdmod;
diff --git a/src/nvim/option.c b/src/nvim/option.c
index e261f06b42..9ad8256f16 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -3933,7 +3933,7 @@ static bool switch_option_context(void *const ctx, OptScope scope, void *const f
         == FAIL) {
       restore_win_noblock(switchwin, true);
 
-      if (try_end(err)) {
+      if (ERROR_SET(err)) {
         return false;
       }
       api_set_error(err, kErrorTypeException, "Problem while switching windows");