From cc2affea11781d4ad1e1b9d7a9c7d729064c2c10 Mon Sep 17 00:00:00 2001
From: Maxime Coste <frrrwww@gmail.com>
Date: Thu, 13 Oct 2016 21:37:44 +0100
Subject: [PATCH] Always allow to delete a buffer, just recreate a scratch
 buffer if needed

Fixes #850
---
 src/buffer_manager.cc |  4 ++--
 src/client.cc         |  3 ++-
 src/client_manager.cc | 26 +++++++-------------------
 src/commands.cc       |  3 ---
 4 files changed, 11 insertions(+), 25 deletions(-)

diff --git a/src/buffer_manager.cc b/src/buffer_manager.cc
index bc88a752..ea6519e2 100644
--- a/src/buffer_manager.cc
+++ b/src/buffer_manager.cc
@@ -57,11 +57,11 @@ void BufferManager::delete_buffer(Buffer& buffer)
                       { return p.get() == &buffer; });
     kak_assert(it != m_buffers.end());
 
-    ClientManager::instance().ensure_no_client_uses_buffer(buffer);
-
     m_buffer_trash.emplace_back(std::move(*it));
     m_buffers.erase(it);
 
+    ClientManager::instance().ensure_no_client_uses_buffer(buffer);
+
     buffer.on_unregistered();
 }
 
diff --git a/src/client.cc b/src/client.cc
index a2d06cf0..405a82d8 100644
--- a/src/client.cc
+++ b/src/client.cc
@@ -144,7 +144,8 @@ void Client::change_buffer(Buffer& buffer)
     if (m_buffer_reload_dialog_opened)
         close_buffer_reload_dialog();
 
-    m_last_buffer = &m_window->buffer();
+    auto* current = &m_window->buffer();
+    m_last_buffer = contains(BufferManager::instance(), current) ? current : nullptr;
 
     auto& client_manager = ClientManager::instance();
     m_window->options().unregister_watcher(*this);
diff --git a/src/client_manager.cc b/src/client_manager.cc
index 889f0777..666df922 100644
--- a/src/client_manager.cc
+++ b/src/client_manager.cc
@@ -109,33 +109,21 @@ void ClientManager::ensure_no_client_uses_buffer(Buffer& buffer)
 {
     for (auto& client : m_clients)
     {
-        client->context().jump_list().forget_buffer(buffer);
+        auto& context = client->context();
+        context.jump_list().forget_buffer(buffer);
         if (client->last_buffer() == &buffer)
             client->set_last_buffer(nullptr);
 
-        if (&client->context().buffer() != &buffer)
+        if (&context.buffer() != &buffer)
             continue;
 
-        if (client->context().is_editing())
+        if (context.is_editing())
             throw runtime_error(format("client '{}' is inserting in buffer '{}'",
-                                       client->context().name(),
+                                       context.name(),
                                        buffer.display_name()));
 
-        if (Buffer* last_buffer = client->last_buffer())
-        {
-            client->context().change_buffer(*last_buffer);
-            continue;
-        }
-
-        for (auto& buf : BufferManager::instance())
-        {
-            if (buf.get() != &buffer)
-            {
-               client->context().change_buffer(*buf);
-               client->set_last_buffer(nullptr);
-               break;
-            }
-        }
+        Buffer* last = client->last_buffer();
+        context.change_buffer(last ? *last : BufferManager::instance().get_first_buffer());
     }
     auto end = std::remove_if(m_free_windows.begin(), m_free_windows.end(),
                               [&buffer](const WindowAndSelections& ws)
diff --git a/src/commands.cc b/src/commands.cc
index cae54822..b5034959 100644
--- a/src/commands.cc
+++ b/src/commands.cc
@@ -566,9 +566,6 @@ void delete_buffer(const ParametersParser& parser, Context& context, const Shell
     if (not force and (buffer.flags() & Buffer::Flags::File) and buffer.is_modified())
         throw runtime_error(format("buffer '{}' is modified", buffer.name()));
 
-    if (manager.count() == 1)
-        throw runtime_error(format("buffer '{}' is the last one", buffer.name()));
-
     manager.delete_buffer(buffer);
 }