vim-patch:8.1.1526: no numerical value for the patchlevel

Problem:    No numerical value for the patchlevel.
Solution:   Add v:versionlong.

37df9a4401

Restore "highest_patch()" solely for "v:versionlong".
Copy/paste Test_vvar_scriptversion2() from patch 9.1.1540.
It works without ":scriptversion 2".
In general, if Vim's test works with ":scriptversion 1", just port it
for additional coverage.

---

vim-patch:8.1.1565: MS-Windows: no sound support

Problem:    MS-Windows: no sound support.
Solution:   Add sound support for MS-Windows. (Yasuhiro Matsumoto, Ken Takata,
            closes vim/vim#4522)

9b283523f2

----

"sound" feature is N/A now but this updates "v:versionlong" docs.

Co-authored-by: Bram Moolenaar <Bram@vim.org>

src/nvim/eval.c

@@ -266,6 +266,7 @@ static struct vimvar {
   VV(VV_TYPE_BOOL,        "t_bool",           VAR_NUMBER, VV_RO),
   VV(VV_TYPE_BLOB,        "t_blob",           VAR_NUMBER, VV_RO),
   VV(VV_EVENT,            "event",            VAR_DICT, VV_RO),
+  VV(VV_VERSIONLONG,      "versionlong",      VAR_NUMBER, VV_RO),
   VV(VV_ECHOSPACE,        "echospace",        VAR_NUMBER, VV_RO),
   VV(VV_ARGV,             "argv",             VAR_LIST, VV_RO),
   VV(VV_COLLATE,          "collate",          VAR_STRING, VV_RO),
@@ -433,6 +434,7 @@ void eval_init(void)
     }
   }
   vimvars[VV_VERSION].vv_nr = VIM_VERSION_100;
+  vimvars[VV_VERSIONLONG].vv_nr = VIM_VERSION_100 * 10000 + highest_patch();
 
   dict_T *const msgpack_types_dict = tv_dict_alloc();
   for (size_t i = 0; i < ARRAY_SIZE(msgpack_type_names); i++) {

src/nvim/eval.h

@@ -162,6 +162,7 @@ typedef enum {
   VV_TYPE_BOOL,
   VV_TYPE_BLOB,
   VV_EVENT,
+  VV_VERSIONLONG,
   VV_ECHOSPACE,
   VV_ARGV,
   VV_COLLATE,

src/nvim/version.c

@@ -2528,6 +2528,12 @@ bool has_nvim_version(const char *const version_str)
                       && patch <= NVIM_VERSION_PATCH))));
 }
 
+int highest_patch(void)
+{
+  // this relies on the highest patch number to be the first entry
+  return included_patches[0];
+}
+
 /// Checks whether a Vim patch has been included.
 ///
 /// @param n Patch number.

src/nvim/vvars.lua

@@ -878,6 +878,21 @@ M.vars = {
       <
     ]=],
   },
+  versionlong = {
+    type = 'integer',
+    desc = [=[
+      Like v:version, but also including the patchlevel in the last
+      four digits.  Version 8.1 with patch 123 has value 8010123.
+      This can be used like this: >
+        if v:versionlong >= 8010123
+      <
+      However, if there are gaps in the list of patches included
+      this will not work well.  This can happen if a recent patch
+      was included into an older version, e.g. for a security fix.
+      Use the has() function to make sure the patch is actually
+      included.
+    ]=],
+  },
   vim_did_enter = {
     type = 'integer',
     desc = [=[