object_to_vim: Fix buffer/window/tabpage conversion on BE systems

Since data.integer is a different (larger) integer type than
data.{buffer,window,tabpage}, we cannot abuse the union by using
data.integer to access the value for all 4 types.  Instead, remove the
{buffer,window,tabpage} members and always use the integer member.

In order to accomodate this, perform distinct validation and coercion
between the Integer type and Buffer/Window/Tabpage types in
object_to_vim, msgpack_rpc helpers, and gendispatch.lua.

1 files changed, 8 insertions, 2 deletions

diff --git a/scripts/gendispatch.lua b/scripts/gendispatch.lua
index 94789e1ef0..397ccc9aaf 100644
--- a/scripts/gendispatch.lua
+++ b/scripts/gendispatch.lua
@@ -232,8 +232,14 @@ for i = 1, #functions do
       converted = 'arg_'..j
       local rt = real_type(param[1])
       if rt ~= 'Object' then
-        output:write('\n  if (args.items['..(j - 1)..'].type == kObjectType'..rt..') {')
-        output:write('\n    '..converted..' = args.items['..(j - 1)..'].data.'..rt:lower()..';')
+        if rt:match('^Buffer$') or rt:match('^Window$') or rt:match('^Tabpage$') then
+          -- Buffer, Window, and Tabpage have a specific type, but are stored in integer
+          output:write('\n  if (args.items['..(j - 1)..'].type == kObjectType'..rt..' && args.items['..(j - 1)..'].data.integer >= 0) {')
+          output:write('\n    '..converted..' = (handle_T)args.items['..(j - 1)..'].data.integer;')
+        else
+          output:write('\n  if (args.items['..(j - 1)..'].type == kObjectType'..rt..') {')
+          output:write('\n    '..converted..' = args.items['..(j - 1)..'].data.'..rt:lower()..';')
+        end
         if rt:match('^Buffer$') or rt:match('^Window$') or rt:match('^Tabpage$') or rt:match('^Boolean$') then
           -- accept nonnegative integers for Booleans, Buffers, Windows and Tabpages
           output:write('\n  } else if (args.items['..(j - 1)..'].type == kObjectTypeInteger && args.items['..(j - 1)..'].data.integer >= 0) {')