api: allow open non-current buffer as terminal (+ xmas bonus)

vim.api.nvim_chan_send(vim.api.nvim_open_term(0), io.open("/path/to/smile.cat", "r"):read("*a"))

src/nvim/api/vim.c

@@ -39,6 +39,7 @@
 #include "nvim/eval/typval.h"
 #include "nvim/eval/userfunc.h"
 #include "nvim/fileio.h"
+#include "nvim/move.h"
 #include "nvim/ops.h"
 #include "nvim/option.h"
 #include "nvim/state.h"
@@ -1246,6 +1247,99 @@ fail:
   return 0;
 }
 
+/// Open a terminal instance in a buffer
+///
+/// By default (and currently the only option) the terminal will not be
+/// connected to an external process. Instead, input send on the channel
+/// will be echoed directly by the terminal. This is useful to disply
+/// ANSI terminal sequences returned as part of a rpc message, or similar.
+///
+/// Note: to directly initiate the terminal using the right size, display the
+/// buffer in a configured window before calling this. For instance, for a
+/// floating display, first create an empty buffer using |nvim_create_buf()|,
+/// then display it using |nvim_open_win()|, and then  call this function.
+/// Then |nvim_chan_send()| cal be called immediately to process sequences
+/// in a virtual terminal having the intended size.
+///
+/// @param buffer the buffer to use (expected to be empty)
+/// @param opts   Optional parameters. Reserved for future use.
+/// @param[out] err Error details, if any
+Integer nvim_open_term(Buffer buffer, Dictionary opts, Error *err)
+  FUNC_API_SINCE(7)
+{
+  buf_T *buf = find_buffer_by_handle(buffer, err);
+  if (!buf) {
+    return 0;
+  }
+
+  if (opts.size > 0) {
+    api_set_error(err, kErrorTypeValidation, "opts dict isn't empty");
+    return 0;
+  }
+
+  TerminalOptions topts;
+  Channel *chan = channel_alloc(kChannelStreamInternal);
+  topts.data = chan;
+  // NB: overriden in terminal_check_size if a window is already
+  // displaying the buffer
+  topts.width = (uint16_t)MAX(curwin->w_width_inner - win_col_off(curwin), 0);
+  topts.height = (uint16_t)curwin->w_height_inner;
+  topts.write_cb = term_write;
+  topts.resize_cb = term_resize;
+  topts.close_cb = term_close;
+  Terminal *term = terminal_open(buf, topts);
+  terminal_check_size(term);
+  chan->term = term;
+  channel_incref(chan);
+  return (Integer)chan->id;
+}
+
+static void term_write(char *buf, size_t size, void *data)
+{
+  // TODO(bfredl): lua callback
+}
+
+static void term_resize(uint16_t width, uint16_t height, void *data)
+{
+  // TODO(bfredl): lua callback
+}
+
+static void term_close(void *data)
+{
+  Channel *chan = data;
+  terminal_destroy(chan->term);
+  chan->term = NULL;
+  channel_decref(chan);
+}
+
+
+/// Send data to channel `id`. For a job, it writes it to the
+/// stdin of the process. For the stdio channel |channel-stdio|,
+/// it writes to Nvim's stdout.  For an internal terminal instance
+/// (|nvim_open_term()|) it writes directly to terimal output.
+/// See |channel-bytes| for more information.
+///
+/// This function writes raw data, not RPC messages.  If the channel
+/// was created with `rpc=true` then the channel expects RPC
+/// messages, use |vim.rpcnotify()| and |vim.rpcrequest()| instead.
+///
+/// @param chan id of the channel
+/// @param data data to write. 8-bit clean: can contain NUL bytes.
+/// @param[out] err Error details, if any
+void nvim_chan_send(Integer chan, String data, Error *err)
+  FUNC_API_SINCE(7) FUNC_API_REMOTE_ONLY FUNC_API_LUA_ONLY
+{
+  const char *error = NULL;
+  if (!data.size) {
+    return;
+  }
+
+  channel_send((uint64_t)chan, data.data, data.size, &error);
+  if (error) {
+    api_set_error(err, kErrorTypeValidation, "%s", error);
+  }
+}
+
 /// Open a new window.
 ///
 /// Currently this is used to open floating and external windows.

src/nvim/channel.c

@@ -161,7 +161,7 @@ void channel_init(void)
 ///
 /// Channel is allocated with refcount 1, which should be decreased
 /// when the underlying stream closes.
-static Channel *channel_alloc(ChannelStreamType type)
+Channel *channel_alloc(ChannelStreamType type)
 {
   Channel *chan = xcalloc(1, sizeof(*chan));
   if (type == kChannelStreamStdio) {
@@ -503,7 +503,7 @@ size_t channel_send(uint64_t id, char *data, size_t len, const char **error)
 {
   Channel *chan = find_channel(id);
   if (!chan) {
-    EMSG(_(e_invchan));
+    *error = _(e_invchan);
     goto err;
   }
 
@@ -518,6 +518,11 @@ size_t channel_send(uint64_t id, char *data, size_t len, const char **error)
     return len * written;
   }
 
+  if (chan->streamtype == kChannelStreamInternal && chan->term) {
+    terminal_receive(chan->term, data, len);
+    return len;
+  }
+
 
   Stream *in = channel_instream(chan);
   if (in->closed) {
@@ -724,8 +729,8 @@ static void channel_callback_call(Channel *chan, CallbackReader *reader)
 /// Open terminal for channel
 ///
 /// Channel `chan` is assumed to be an open pty channel,
-/// and curbuf is assumed to be a new, unmodified buffer.
-void channel_terminal_open(Channel *chan)
+/// and `buf` is assumed to be a new, unmodified buffer.
+void channel_terminal_open(buf_T *buf, Channel *chan)
 {
   TerminalOptions topts;
   topts.data = chan;
@@ -734,8 +739,8 @@ void channel_terminal_open(Channel *chan)
   topts.write_cb = term_write;
   topts.resize_cb = term_resize;
   topts.close_cb = term_close;
-  curbuf->b_p_channel = (long)chan->id;  // 'channel' option
-  Terminal *term = terminal_open(topts);
+  buf->b_p_channel = (long)chan->id;  // 'channel' option
+  Terminal *term = terminal_open(buf, topts);
   chan->term = term;
   channel_incref(chan);
 }

src/nvim/eval/funcs.c

@@ -10731,7 +10731,7 @@ static void f_termopen(typval_T *argvars, typval_T *rettv, FunPtr fptr)
                INTEGER_OBJ(pid), false, false, &err);
   api_clear_error(&err);
 
-  channel_terminal_open(chan);
+  channel_terminal_open(curbuf, chan);
   channel_create_event(chan, NULL);
 }
 

src/nvim/generators/gen_api_dispatch.lua

@@ -104,8 +104,11 @@ for _,f in ipairs(shallowcopy(functions)) do
     elseif startswith(f.name, "nvim_tabpage_") then
       ismethod = true
     end
+    f.remote = f.remote_only or not f.lua_only
+    f.lua = f.lua_only or not f.remote_only
+    f.eval = (not f.lua_only) and (not f.remote_only)
   else
-    f.remote_only = true
+    f.remote = true
     f.since = 0
     f.deprecated_since = 1
   end
@@ -127,7 +130,8 @@ for _,f in ipairs(shallowcopy(functions)) do
       newf.return_type = "Object"
     end
     newf.impl_name = f.name
-    newf.remote_only = true
+    newf.lua = false
+    newf.eval = false
     newf.since = 0
     newf.deprecated_since = 1
     functions[#functions+1] = newf
@@ -192,7 +196,7 @@ end
 -- the real API.
 for i = 1, #functions do
   local fn = functions[i]
-  if fn.impl_name == nil and not fn.lua_only then
+  if fn.impl_name == nil and fn.remote then
     local args = {}
 
     output:write('Object handle_'..fn.name..'(uint64_t channel_id, Array args, Error *error)')
@@ -323,7 +327,7 @@ void msgpack_rpc_init_method_table(void)
 
 for i = 1, #functions do
   local fn = functions[i]
-  if not fn.lua_only then
+  if fn.remote then
       output:write('  msgpack_rpc_add_method_handler('..
                    '(String) {.data = "'..fn.name..'", '..
                    '.size = sizeof("'..fn.name..'") - 1}, '..
@@ -492,7 +496,7 @@ local function process_function(fn)
 end
 
 for _, fn in ipairs(functions) do
-  if not fn.remote_only or fn.name:sub(1, 4) == '_vim' then
+  if fn.lua or fn.name:sub(1, 4) == '_vim' then
     process_function(fn)
   end
 end

src/nvim/generators/gen_eval.lua

@@ -25,7 +25,7 @@ local gperfpipe = io.open(funcsfname .. '.gperf', 'wb')
 local funcs = require('eval').funcs
 local metadata = mpack.unpack(io.open(metadata_file, 'rb'):read("*all"))
 for _,fun in ipairs(metadata) do
-  if not (fun.remote_only or fun.lua_only) then
+  if fun.eval then
     funcs[fun.name] = {
       args=#fun.parameters,
       func='api_wrapper',

src/nvim/terminal.c

@@ -169,19 +169,20 @@ void terminal_teardown(void)
   multiqueue_free(refresh_timer.events);
   time_watcher_close(&refresh_timer, NULL);
   pmap_free(ptr_t)(invalidated_terminals);
+  invalidated_terminals = NULL;
 }
 
 // public API {{{
 
-Terminal *terminal_open(TerminalOptions opts)
+Terminal *terminal_open(buf_T *buf, TerminalOptions opts)
 {
   // Create a new terminal instance and configure it
   Terminal *rv = xcalloc(1, sizeof(Terminal));
   rv->opts = opts;
   rv->cursor.visible = true;
   // Associate the terminal instance with the new buffer
-  rv->buf_handle = curbuf->handle;
-  curbuf->terminal = rv;
+  rv->buf_handle = buf->handle;
+  buf->terminal = rv;
   // Create VTerm
   rv->vt = vterm_new(opts.height, opts.width);
   vterm_set_utf8(rv->vt, 1);
@@ -198,28 +199,36 @@ Terminal *terminal_open(TerminalOptions opts)
   // have as many lines as screen rows when refresh_scrollback is called
   rv->invalid_start = 0;
   rv->invalid_end = opts.height;
-  refresh_screen(rv, curbuf);
+
+  aco_save_T aco;
+  aucmd_prepbuf(&aco, buf);
+
+  refresh_screen(rv, buf);
   set_option_value("buftype", 0, "terminal", OPT_LOCAL);  // -V666
 
   // Default settings for terminal buffers
-  curbuf->b_p_ma = false;     // 'nomodifiable'
-  curbuf->b_p_ul = -1;        // 'undolevels'
-  curbuf->b_p_scbk =          // 'scrollback' (initialize local from global)
+  buf->b_p_ma = false;     // 'nomodifiable'
+  buf->b_p_ul = -1;        // 'undolevels'
+  buf->b_p_scbk =          // 'scrollback' (initialize local from global)
     (p_scbk < 0) ? 10000 : MAX(1, p_scbk);
-  curbuf->b_p_tw = 0;         // 'textwidth'
+  buf->b_p_tw = 0;         // 'textwidth'
   set_option_value("wrap", false, NULL, OPT_LOCAL);
   set_option_value("list", false, NULL, OPT_LOCAL);
-  buf_set_term_title(curbuf, (char *)curbuf->b_ffname);
+  if (buf->b_ffname != NULL) {
+    buf_set_term_title(buf, (char *)buf->b_ffname);
+  }
   RESET_BINDING(curwin);
   // Reset cursor in current window.
   curwin->w_cursor = (pos_T){ .lnum = 1, .col = 0, .coladd = 0 };
   // Apply TermOpen autocmds _before_ configuring the scrollback buffer.
-  apply_autocmds(EVENT_TERMOPEN, NULL, NULL, false, curbuf);
+  apply_autocmds(EVENT_TERMOPEN, NULL, NULL, false, buf);
   // Local 'scrollback' _after_ autocmds.
-  curbuf->b_p_scbk = (curbuf->b_p_scbk < 1) ? SB_MAX : curbuf->b_p_scbk;
+  buf->b_p_scbk = (buf->b_p_scbk < 1) ? SB_MAX : buf->b_p_scbk;
+
+  aucmd_restbuf(&aco);
 
   // Configure the scrollback buffer.
-  rv->sb_size = (size_t)curbuf->b_p_scbk;
+  rv->sb_size = (size_t)buf->b_p_scbk;
   rv->sb_buffer = xmalloc(sizeof(ScrollbackLine *) * rv->sb_size);
 
   // Configure the color palette. Try to get the color from:
@@ -511,7 +520,9 @@ void terminal_destroy(Terminal *term)
   }
 
   if (!term->refcount) {
-    if (pmap_has(ptr_t)(invalidated_terminals, term)) {
+    // might be destroyed after terminal_teardown is invoked
+    if (invalidated_terminals
+        && pmap_has(ptr_t)(invalidated_terminals, term)) {
       // flush any pending changes to the buffer
       block_autocmds();
       refresh_terminal(term);
@@ -1324,6 +1335,7 @@ static void refresh_scrollback(Terminal *term, buf_T *buf)
 // focused) of a invalidated terminal
 static void refresh_screen(Terminal *term, buf_T *buf)
 {
+  assert(buf == curbuf);  // TODO(bfredl): remove this condition
   int changed = 0;
   int added = 0;
   int height;

test/functional/api/vim_spec.lua

@@ -2087,4 +2087,67 @@ describe('API', function()
       eq("", meths.exec("messages", true))
     end)
   end)
+
+
+  describe('nvim_open_term', function()
+    local screen
+
+    before_each(function()
+      clear()
+      screen = Screen.new(100, 35)
+      screen:attach()
+      screen:set_default_attr_ids({
+        [0] = {bold=true, foreground=Screen.colors.Blue},
+        [1] = {background = Screen.colors.Plum1};
+        [2] = {background = tonumber('0xffff40'), bg_indexed = true};
+        [3] = {background = Screen.colors.Plum1, fg_indexed = true, foreground = tonumber('0x00e000')};
+        [4] = {bold = true, reverse = true, background = Screen.colors.Plum1};
+      })
+    end)
+
+    it('can batch process sequences', function()
+      local b = meths.create_buf(true,true)
+      meths.open_win(b, false, {width=79, height=31, row=1, col=1, relative='editor'})
+      local t = meths.open_term(b, {})
+
+      meths.chan_send(t, io.open("test/functional/fixtures/smile2.cat", "r"):read("*a"))
+      screen:expect{grid=[[
+        ^                                                                                                    |
+        {0:~}{1::smile                                                                         }{0:                    }|
+        {0:~}{1:                            }{2:oooo$$$$$$$$$$$$oooo}{1:                               }{0:                    }|
+        {0:~}{1:                        }{2:oo$$$$$$$$$$$$$$$$$$$$$$$$o}{1:                            }{0:                    }|
+        {0:~}{1:                     }{2:oo$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$o}{1:         }{2:o$}{1:   }{2:$$}{1: }{2:o$}{1:      }{0:                    }|
+        {0:~}{1:     }{2:o}{1: }{2:$}{1: }{2:oo}{1:        }{2:o$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$o}{1:       }{2:$$}{1: }{2:$$}{1: }{2:$$o$}{1:     }{0:                    }|
+        {0:~}{1:  }{2:oo}{1: }{2:$}{1: }{2:$}{1: "}{2:$}{1:      }{2:o$$$$$$$$$}{1:    }{2:$$$$$$$$$$$$$}{1:    }{2:$$$$$$$$$o}{1:       }{2:$$$o$$o$}{1:      }{0:                    }|
+        {0:~}{1:  "}{2:$$$$$$o$}{1:     }{2:o$$$$$$$$$}{1:      }{2:$$$$$$$$$$$}{1:      }{2:$$$$$$$$$$o}{1:    }{2:$$$$$$$$}{1:       }{0:                    }|
+        {0:~}{1:    }{2:$$$$$$$}{1:    }{2:$$$$$$$$$$$}{1:      }{2:$$$$$$$$$$$}{1:      }{2:$$$$$$$$$$$$$$$$$$$$$$$}{1:       }{0:                    }|
+        {0:~}{1:    }{2:$$$$$$$$$$$$$$$$$$$$$$$}{1:    }{2:$$$$$$$$$$$$$}{1:    }{2:$$$$$$$$$$$$$$}{1:  """}{2:$$$}{1:         }{0:                    }|
+        {0:~}{1:     "}{2:$$$}{1:""""}{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:     "}{2:$$$}{1:        }{0:                    }|
+        {0:~}{1:      }{2:$$$}{1:   }{2:o$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:     "}{2:$$$o}{1:      }{0:                    }|
+        {0:~}{1:     }{2:o$$}{1:"   }{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:       }{2:$$$o}{1:     }{0:                    }|
+        {0:~}{1:     }{2:$$$}{1:    }{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:" "}{2:$$$$$$ooooo$$$$o}{1:   }{0:                    }|
+        {0:~}{1:    }{2:o$$$oooo$$$$$}{1:  }{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:   }{2:o$$$$$$$$$$$$$$$$$}{1:  }{0:                    }|
+        {0:~}{1:    }{2:$$$$$$$$}{1:"}{2:$$$$}{1:   }{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:     }{2:$$$$}{1:""""""""        }{0:                    }|
+        {0:~}{1:   """"       }{2:$$$$}{1:    "}{2:$$$$$$$$$$$$$$$$$$$$$$$$$$$$}{1:"      }{2:o$$$}{1:                 }{0:                    }|
+        {0:~}{1:              "}{2:$$$o}{1:     """}{2:$$$$$$$$$$$$$$$$$$}{1:"}{2:$$}{1:"         }{2:$$$}{1:                  }{0:                    }|
+        {0:~}{1:                }{2:$$$o}{1:          "}{2:$$}{1:""}{2:$$$$$$}{1:""""           }{2:o$$$}{1:                   }{0:                    }|
+        {0:~}{1:                 }{2:$$$$o}{1:                                }{2:o$$$}{1:"                    }{0:                    }|
+        {0:~}{1:                  "}{2:$$$$o}{1:      }{2:o$$$$$$o}{1:"}{2:$$$$o}{1:        }{2:o$$$$}{1:                      }{0:                    }|
+        {0:~}{1:                    "}{2:$$$$$oo}{1:     ""}{2:$$$$o$$$$$o}{1:   }{2:o$$$$}{1:""                       }{0:                    }|
+        {0:~}{1:                       ""}{2:$$$$$oooo}{1:  "}{2:$$$o$$$$$$$$$}{1:"""                          }{0:                    }|
+        {0:~}{1:                          ""}{2:$$$$$$$oo}{1: }{2:$$$$$$$$$$}{1:                               }{0:                    }|
+        {0:~}{1:                                  """"}{2:$$$$$$$$$$$}{1:                              }{0:                    }|
+        {0:~}{1:                                      }{2:$$$$$$$$$$$$}{1:                             }{0:                    }|
+        {0:~}{1:                                       }{2:$$$$$$$$$$}{1:"                             }{0:                    }|
+        {0:~}{1:                                        "}{2:$$$}{1:""""                               }{0:                    }|
+        {0:~}{1:                                                                               }{0:                    }|
+        {0:~}{3:Press ENTER or type command to continue}{1:                                        }{0:                    }|
+        {0:~}{4:term://~/config2/docs/pres//32693:vim --clean +smile         29,39          All}{0:                    }|
+        {0:~}{1::call nvim__screenshot("smile2.cat")                                           }{0:                    }|
+        {0:~                                                                                                   }|
+        {0:~                                                                                                   }|
+                                                                                                            |
+      ]]}
+    end)
+  end)
 end)

test/functional/fixtures/smile2.cat

@@ -0,0 +1,32 @@
+31,79
+[?25l:smile                                                                         
+                            oooo$$$$$$$$$$$$oooo(B                               
+                        oo$$$$$$$$$$$$$$$$$$$$$$$$o(B                            
+                     oo$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$o(B         o$(B   $$(B o$(B      
+     o(B $(B oo(B        o$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$o(B       $$(B $$(B $$o$(B     
+  oo(B $(B $(B "$(B      o$$$$$$$$$(B    $$$$$$$$$$$$$(B    $$$$$$$$$o(B       $$$o$$o$(B      
+  "$$$$$$o$(B     o$$$$$$$$$(B      $$$$$$$$$$$(B      $$$$$$$$$$o(B    $$$$$$$$(B       
+    $$$$$$$(B    $$$$$$$$$$$(B      $$$$$$$$$$$(B      $$$$$$$$$$$$$$$$$$$$$$$(B       
+    $$$$$$$$$$$$$$$$$$$$$$$(B    $$$$$$$$$$$$$(B    $$$$$$$$$$$$$$(B  """$$$(B         
+     "$$$(B""""$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$(B     "$$$(B        
+      $$$(B   o$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$(B     "$$$o(B      
+     o$$(B"   $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$(B       $$$o(B     
+     $$$(B    $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$(B" "$$$$$$ooooo$$$$o(B   
+    o$$$oooo$$$$$(B  $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$(B   o$$$$$$$$$$$$$$$$$(B  
+    $$$$$$$$(B"$$$$(B   $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$(B     $$$$(B""""""""        
+   """"       $$$$(B    "$$$$$$$$$$$$$$$$$$$$$$$$$$$$(B"      o$$$(B                 
+              "$$$o(B     """$$$$$$$$$$$$$$$$$$(B"$$(B"         $$$(B                  
+                $$$o(B          "$$(B""$$$$$$(B""""           o$$$(B                   
+                 $$$$o(B                                o$$$(B"                    
+                  "$$$$o(B      o$$$$$$o(B"$$$$o(B        o$$$$(B                      
+                    "$$$$$oo(B     ""$$$$o$$$$$o(B   o$$$$(B""                       
+                       ""$$$$$oooo(B  "$$$o$$$$$$$$$(B"""                          
+                          ""$$$$$$$oo(B $$$$$$$$$$(B                               
+                                  """"$$$$$$$$$$$(B                              
+                                      $$$$$$$$$$$$(B                             
+                                       $$$$$$$$$$(B"                             
+                                        "$$$(B""""                               
+                                                                               
+Press ENTER or type command to continue(B                                        
+(Bterm://~/config2/docs/pres//32693:vim --clean +smile         29,39          All
+(B:call nvim__screenshot("smile2.cat")                                           [?25h