vim-patch:8.1.1437: code to handle callbacks is duplicated

Problem:    Code to handle callbacks is duplicated.
Solution:   Add callback_T and functions to deal with it.
3a97bb3f0f

Port Vim's put_callback() as callback_put()
because Neovim's naming convention is {type}_{action},
not {action}_{type}.

Renaming put_callback type as PutCallback.
https://neovim.io/develop/style-guide.xml#Type_Names

src/nvim/eval.c

@@ -7324,14 +7324,7 @@ void add_timer_info(typval_T *rettv, timer_T *timer)
     return;
   }
 
-  if (timer->callback.type == kCallbackPartial) {
-    di->di_tv.v_type = VAR_PARTIAL;
-    di->di_tv.vval.v_partial = timer->callback.data.partial;
-    timer->callback.data.partial->pt_refcount++;
-  } else if (timer->callback.type == kCallbackFuncref) {
-    di->di_tv.v_type = VAR_FUNC;
-    di->di_tv.vval.v_string = vim_strsave(timer->callback.data.funcref);
-  }
+  callback_put(&timer->callback, &di->di_tv);
 }
 
 void add_timer_info_all(typval_T *rettv)

src/nvim/eval/typval.c

@@ -1164,6 +1164,21 @@ void callback_free(Callback *callback)
   callback->type = kCallbackNone;
 }
 
+/// Copy a callback into a typval_T.
+void callback_put(Callback *cb, typval_T *tv)
+  FUNC_ATTR_NONNULL_ALL
+{
+  if (cb->type == kCallbackPartial) {
+    tv->v_type = VAR_PARTIAL;
+    tv->vval.v_partial = cb->data.partial;
+    cb->data.partial->pt_refcount++;
+  } else if (cb->type == kCallbackFuncref) {
+    tv->v_type = VAR_FUNC;
+    tv->vval.v_string = vim_strsave(cb->data.funcref);
+    func_ref(cb->data.funcref);
+  }
+}
+
 /// Remove watcher from a dictionary
 ///
 /// @param  dict  Dictionary to remove watcher from.

src/nvim/event/multiqueue.c

@@ -73,7 +73,7 @@ struct multiqueue_item {
 struct multiqueue {
   MultiQueue *parent;
   QUEUE headtail;  // circularly-linked
-  put_callback put_cb;
+  PutCallback put_cb;
   void *data;
   size_t size;
 };
@@ -91,7 +91,7 @@ typedef struct {
 
 static Event NILEVENT = { .handler = NULL, .argv = {NULL} };
 
-MultiQueue *multiqueue_new_parent(put_callback put_cb, void *data)
+MultiQueue *multiqueue_new_parent(PutCallback put_cb, void *data)
 {
   return multiqueue_new(NULL, put_cb, data);
 }
@@ -104,7 +104,7 @@ MultiQueue *multiqueue_new_child(MultiQueue *parent)
   return multiqueue_new(parent, NULL, NULL);
 }
 
-static MultiQueue *multiqueue_new(MultiQueue *parent, put_callback put_cb,
+static MultiQueue *multiqueue_new(MultiQueue *parent, PutCallback put_cb,
                                   void *data)
 {
   MultiQueue *rv = xmalloc(sizeof(MultiQueue));

src/nvim/event/multiqueue.h

@@ -7,7 +7,7 @@
 #include "nvim/lib/queue.h"
 
 typedef struct multiqueue MultiQueue;
-typedef void (*put_callback)(MultiQueue *multiq, void *data);
+typedef void (*PutCallback)(MultiQueue *multiq, void *data);
 
 #define multiqueue_put(q, h, ...) \
   multiqueue_put_event(q, event_create(h, __VA_ARGS__));