Send changedtick as first event if buffer contents weren't requested

3 files changed, 41 insertions, 35 deletions

diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index 756367f801..12d1feb370 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -80,7 +80,9 @@ String buffer_get_line(Buffer buffer, Integer index, Error *err)
 ///
 /// @param buffer The buffer handle
 /// @param send_buffer Set to true if the initial notification should contain
-///        the whole buffer
+///        the whole buffer. If so, the first notification will be a
+///        `nvim_buf_lines_event`. Otherwise, the first notification will be
+///        a `nvim_buf_changedtick_event`
 /// @param[out] err Details of an error that may have occurred
 /// @return False when updates couldn't be enabled because the buffer isn't
 ///         loaded; otherwise True.
diff --git a/src/nvim/buffer_updates.c b/src/nvim/buffer_updates.c
index 71ca800ee5..2852561ce0 100644
--- a/src/nvim/buffer_updates.c
+++ b/src/nvim/buffer_updates.c
@@ -28,20 +28,20 @@ bool buf_updates_register(buf_T *buf, uint64_t channel_id, bool send_buffer)
   // append the channelid to the list
   kv_push(buf->update_channels, channel_id);
 
-  Array args = ARRAY_DICT_INIT;
-  args.size = 6;
-  args.items = xcalloc(sizeof(Object), args.size);
-
-  // the first argument is always the buffer handle
-  args.items[0] = BUFFER_OBJ(buf->handle);
-  args.items[1] = INTEGER_OBJ(buf->b_changedtick);
-  // the first line that changed (zero-indexed)
-  args.items[2] = INTEGER_OBJ(-1);
-  // the last line that was changed
-  args.items[3] = INTEGER_OBJ(-1);
-  Array linedata = ARRAY_DICT_INIT;
-
   if (send_buffer) {
+    Array args = ARRAY_DICT_INIT;
+    args.size = 6;
+    args.items = xcalloc(sizeof(Object), args.size);
+
+    // the first argument is always the buffer handle
+    args.items[0] = BUFFER_OBJ(buf->handle);
+    args.items[1] = INTEGER_OBJ(buf->b_changedtick);
+    // the first line that changed (zero-indexed)
+    args.items[2] = INTEGER_OBJ(0);
+    // the last line that was changed
+    args.items[3] = INTEGER_OBJ(-1);
+    Array linedata = ARRAY_DICT_INIT;
+
     // collect buffer contents
 
     // True now, but a compile time reminder for future systems we support
@@ -50,8 +50,6 @@ bool buf_updates_register(buf_T *buf, uint64_t channel_id, bool send_buffer)
     size_t line_count = (size_t)buf->b_ml.ml_line_count;
 
     if (line_count >= 1) {
-      args.items[2] = INTEGER_OBJ(0);
-
       linedata.size = line_count;
       linedata.items = xcalloc(sizeof(Object), line_count);
       for (size_t i = 0; i < line_count; i++) {
@@ -66,12 +64,15 @@ bool buf_updates_register(buf_T *buf, uint64_t channel_id, bool send_buffer)
         linedata.items[i] = str;
       }
     }
-  }
 
-  args.items[4] = ARRAY_OBJ(linedata);
-  args.items[5] = BOOLEAN_OBJ(false);
+    args.items[4] = ARRAY_OBJ(linedata);
+    args.items[5] = BOOLEAN_OBJ(false);
+
+    rpc_send_event(channel_id, "nvim_buf_lines_event", args);
+  } else {
+    buf_updates_changedtick_single(buf, channel_id);
+  }
 
-  rpc_send_event(channel_id, "nvim_buf_lines_event", args);
   return true;
 }
 
@@ -207,9 +208,13 @@ void buf_updates_changedtick(buf_T *buf)
 {
   // notify each of the active channels
   for (size_t i = 0; i < kv_size(buf->update_channels); i++) {
-    uint64_t channelid = kv_A(buf->update_channels, i);
+    uint64_t channel_id = kv_A(buf->update_channels, i);
+    buf_updates_changedtick_single(buf, channel_id);
+  }
+}
 
-    // send through the changes now channel contents now
+void buf_updates_changedtick_single(buf_T *buf, uint64_t channel_id)
+{
     Array args = ARRAY_DICT_INIT;
     args.size = 2;
     args.items = xcalloc(sizeof(Object), args.size);
@@ -221,6 +226,5 @@ void buf_updates_changedtick(buf_T *buf)
     args.items[1] = INTEGER_OBJ(buf->b_changedtick);
 
     // don't try and clean up dead channels here
-    rpc_send_event(channelid, "nvim_buf_changedtick", args);
-  }
+    rpc_send_event(channel_id, "nvim_buf_changedtick_event", args);
 }
diff --git a/test/functional/api/buffer_updates_spec.lua b/test/functional/api/buffer_updates_spec.lua
index 3f15c8a8a5..1bbba91187 100644
--- a/test/functional/api/buffer_updates_spec.lua
+++ b/test/functional/api/buffer_updates_spec.lua
@@ -338,7 +338,7 @@ describe('buffer events', function()
     tick = tick + 1
     expectn('nvim_buf_lines_event', {b, tick, 1, 2, {}, false})
     tick = tick + 1
-    expectn('nvim_buf_changedtick', {b, tick})
+    expectn('nvim_buf_changedtick_event', {b, tick})
     command('set autoindent')
     command('normal! >>')
     tick = tick + 1
@@ -356,7 +356,7 @@ describe('buffer events', function()
     tick = tick + 1
     expectn('nvim_buf_lines_event', {b, tick, 1, 2, {}, false})
     tick = tick + 1
-    expectn('nvim_buf_changedtick', {b, tick})
+    expectn('nvim_buf_changedtick_event', {b, tick})
     command('normal! ggOmmm')
     tick = tick + 1
     expectn('nvim_buf_lines_event', {b, tick, 0, 0, {"\t"}, false})
@@ -376,7 +376,7 @@ describe('buffer events', function()
     tick = tick + 1
     expectn('nvim_buf_lines_event', {b, tick, 0, 1, {'Line 1'}, false})
     tick = tick + 1
-    expectn('nvim_buf_changedtick', {b, tick})
+    expectn('nvim_buf_changedtick_event', {b, tick})
 
     -- change the file directly
     local f = io.open(filename, 'a')
@@ -412,7 +412,7 @@ describe('buffer events', function()
     tick1 = tick1 + 1
     expectn('nvim_buf_lines_event', {b1, tick1, 0, 1, {'A1'}, false})
     tick1 = tick1 + 1
-    expectn('nvim_buf_changedtick', {b1, tick1})
+    expectn('nvim_buf_changedtick_event', {b1, tick1})
 
     command('b'..b2nr)
     command('normal! x')
@@ -422,7 +422,7 @@ describe('buffer events', function()
     tick2 = tick2 + 1
     expectn('nvim_buf_lines_event', {b2, tick2, 0, 1, {'B1'}, false})
     tick2 = tick2 + 1
-    expectn('nvim_buf_changedtick', {b2, tick2})
+    expectn('nvim_buf_changedtick_event', {b2, tick2})
 
     command('b'..b3nr)
     command('normal! x')
@@ -432,7 +432,7 @@ describe('buffer events', function()
     tick3 = tick3 + 1
     expectn('nvim_buf_lines_event', {b3, tick3, 0, 1, {'C1'}, false})
     tick3 = tick3 + 1
-    expectn('nvim_buf_changedtick', {b3, tick3})
+    expectn('nvim_buf_changedtick_event', {b3, tick3})
   end)
 
   it('doesn\'t get confused when you turn watching on/off many times',
@@ -514,8 +514,8 @@ describe('buffer events', function()
     wantn(2, 'nvim_buf_lines_event', {b, tick, 0, 1, {'AAA'}, false})
     wantn(3, 'nvim_buf_lines_event', {b, tick, 0, 1, {'AAA'}, false})
     tick = tick + 1
-    wantn(2, 'nvim_buf_changedtick', {b, tick})
-    wantn(3, 'nvim_buf_changedtick', {b, tick})
+    wantn(2, 'nvim_buf_changedtick_event', {b, tick})
+    wantn(3, 'nvim_buf_changedtick_event', {b, tick})
 
     -- make sure there are no other pending nvim_buf_lines_event messages going to
     -- channel 1
@@ -667,7 +667,7 @@ describe('buffer events', function()
     tick = tick + 1
     expectn('nvim_buf_lines_event', {b, tick, 0, 1, {'AAA'}, false})
     tick = tick + 1
-    expectn('nvim_buf_changedtick', {b, tick})
+    expectn('nvim_buf_changedtick_event', {b, tick})
 
     -- close our buffer by creating a new one
     command('enew')
@@ -694,7 +694,7 @@ describe('buffer events', function()
     tick = tick + 1
     expectn('nvim_buf_lines_event', {b, tick, 0, 1, {'AAA'}, false})
     tick = tick + 1
-    expectn('nvim_buf_changedtick', {b, tick})
+    expectn('nvim_buf_changedtick_event', {b, tick})
 
     -- close our buffer by creating a new one
     command('set hidden')
@@ -733,7 +733,7 @@ describe('buffer events', function()
     helpers.clear()
     local b, tick = editoriginal(false)
     ok(buffer('attach', b, false))
-    expectn('nvim_buf_lines_event', {b, tick, -1, -1, {}, false})
+    expectn('nvim_buf_changedtick_event', {b, tick})
   end)
 
 end)