lua/stdlib: Introduce vim.shared

This is where "pure functions" can live, which can be shared by Nvim and
test logic which may not have a running Nvim instance available.

If in the future we use Nvim itself as the Lua engine for tests, then
these functions could be moved directly onto the `vim` Lua module.

closes #6580
This commit is contained in:
Justin M. Keyes
2019-01-18 00:44:35 +01:00
parent 2b87485c22
commit bba75eb184
5 changed files with 88 additions and 36 deletions

View File

@@ -0,0 +1,39 @@
--- Shared functions
-- - Used by Nvim and tests
-- - Can run in vanilla Lua (do not require a running instance of Nvim)
--- Merge map-like tables.
--
--@see |extend()|
--
-- behavior: Decides what to do if a key is found in more than one map:
-- "error": raise an error
-- "keep": skip
-- "force": set the item again
local function tbl_extend(behavior, ...)
if (behavior ~= 'error' and behavior ~= 'keep' and behavior ~= 'force') then
error('invalid "behavior": '..tostring(behavior))
end
local ret = {}
for i = 1, select('#', ...) do
local tbl = select(i, ...)
if tbl then
for k, v in pairs(tbl) do
if behavior ~= 'force' and ret[k] ~= nil then
if behavior == 'error' then
error('key found in more than one map: '..k)
end -- Else behavior is "keep".
else
ret[k] = v
end
end
end
end
return ret
end
local module = {
tbl_extend = tbl_extend,
}
return module