fix: vim.validate() order is not deterministic #28377

Problem:
The order of the validation performed by vim.validate() is
unpredictable.
- harder to write reliable tests.
- confusing UX because validation result might return different errors randomly.

Solution:
Iterate the input using `vim.spairs()`.

Future:
Ideally, the caller could provide an "ordered dict".

1 files changed, 2 insertions, 1 deletions

diff --git a/runtime/doc/lua.txt b/runtime/doc/lua.txt
index c760e762ee..2c0307a409 100644
--- a/runtime/doc/lua.txt
+++ b/runtime/doc/lua.txt
@@ -2376,7 +2376,8 @@ vim.trim({s})                                                     *vim.trim()*
       • https://www.lua.org/pil/20.2.html
 
 vim.validate({opt})                                           *vim.validate()*
-    Validates a parameter specification (types and values).
+    Validates a parameter specification (types and values). Specs are
+    evaluated in alphanumeric order, until the first failure.
 
     Usage example: >lua
         function user.new(name, age, hobbies)