Recognize deprecated functions that haven't been removed yet.

TODO.md

@@ -22,6 +22,10 @@ refactor brainstorm:
 Here is my feature wishlist. I don't expect to ever get all of this
 done, but these are the sort of enhancements I am thinking about.
 
+- [ ] Improved global checks
+    - [ ] (or table.unpack _G.unpack) should be allowed on any Lua version
+- [ ] generate man page
+- [ ] load lints from external sources (sandboxed)
 - [X] Able to connect to a client
 - [X] Support for UTF-8 characters that aren't just plain ASCII. (especially `λ`) (perhaps just tell the IDE that I want to communicate with utf-8 offsets)
 - [ ] People have tried fennel-ls in:
@@ -30,10 +34,6 @@ done, but these are the sort of enhancements I am thinking about.
     - [X] helix
     - [X] vscode (publish an extension)
     - [ ] vim+coc (publish a node thingy)
-- [ ] Improved global checks
-    - [ ] (or table.unpack _G.unpack) should be allowed on any Lua version
-- [ ] generate man page
-- [ ] load lints from external sources (sandboxed)
 - [x] Go-to-definition:
     - [X] literal table constructor
     - [X] table destructuring

src/fennel-ls/docs.fnl

@@ -37,6 +37,12 @@
 (set lua-versions.lua51.package.fields.config
      lua-versions.lua52.package.fields.config)
 
+;; deprecated but not removed
+(each [_ f (ipairs [:atan2 :cosh :sinh :tanh :pow :frexp :ldexp])]
+  (set (. lua-versions.lua53.math.fields f) (. lua-versions.lua52.math.fields f)))
+
+(set lua-versions.lua53.bit32 lua-versions.lua52.bit32)
+
 (each [_ version (pairs lua-versions)]
   (each [k v (pairs version)]
     (set (. lua-versions.union k) v)))

test/diagnostic.fnl

@@ -155,7 +155,12 @@
          []
          [{:message "unknown identifier: unpack"}
           {:message "unknown identifier: warn"}]
-         {:lua-version "union"}))
+         {:lua-version "union"})
+  ;; deprecated functions still work
+  (check "(print (math.atan2 (tonumber (io.read))))"
+         []
+         [{:message "unknown field: math.atan2"}]
+         {:lua-version "lua5.3"}))
 
 {: test-lua-versions
  : test-compile-error