Add support for :intersection as lua version.

This will only accept globals which are present in every Lua version
from 5.1-5.4. Using this for selflint currently fails, so let's fix
that next.

changelog.md

@@ -4,6 +4,7 @@
 
 ### Features
 * Settings file: `flsproject.fnl`. Settings are now editor agnostic.
+* Support `:intersection` as a Lua version; only includes globals present in every Lua.
 
 ### Bug Fixes
 * (set (. x y) z) wasn't being analyzed properly.

src/fennel-ls/docs.fnl

@@ -22,9 +22,14 @@
   (when (not (. lua-versions version))
     (error (.. "fennel-ls doesn't know about lua version " version "\n"
                "The allowed versions are: "
-               (fennel.view (doto (icollect [key (pairs lua-versions)] key) table.sort)))))
+               (fennel.view (doto (icollect [key (pairs lua-versions)] key)
+                              table.sort)))))
   (. lua-versions version))
 
+(set lua-versions.intersection
+     (collect [k v (pairs lua-versions.lua51)]
+       (if (. lua-versions.lua54 k) (values k v))))
+
 (local libraries
   {:tic-80 (require :fennel-ls.docs.generated.tic80)})
 

test/diagnostic.fnl

@@ -20,8 +20,8 @@
                       (= e.range.end.character   d.range.end.character))))
       i)))
 
-(fn check [file-contents expected unexpected]
-  (let [{: diagnostics} (create-client file-contents)]
+(fn check [file-contents expected unexpected ?opts]
+  (let [{: diagnostics} (create-client file-contents nil ?opts)]
     (each [_ e (ipairs unexpected)]
       (let [i (find diagnostics e)]
         (faith.= nil i (.. "Lint matching " (view e) "\n"
@@ -120,12 +120,12 @@
             (print x +))"
          [{:message "expected condition and body"}
           {:message "tried to reference a special form without calling it"}] [])
-  ;; ;; recovers from missing condition (when)
+  ;; TODO: recovers from missing condition (when)
   ;; (check "(let [x (when)]
   ;;           (print x +))"
   ;;        [{:message #($:find ".*macros.fnl:%d+: expected body")}
   ;;         {:message "tried to reference a special form without calling it"}] [])
-  ;; ;; recovers from missing body (when)
+  ;; TODO: recovers from missing body (when)
   ;; (check "(let [x (when (< (+ 9 10) 21))]
   ;;           (print x +))"
   ;;        [;; {:message #($:find ".*macros.fnl:%d+: expected body")}
@@ -136,7 +136,21 @@
         {:message "tried to reference a special form without calling it"}] [])
   nil)
 
-{: test-compile-error
+(fn test-lua-versions []
+  (check "(local t (unpack []))"
+         [] [{:message "unknown identifier: unpack"}]
+         {:lua-version "lua51"})
+  (check "(local t (unpack []))"
+         [{:message "unknown identifier: unpack"}] []
+         {:lua-version "lua52"})
+  ;; intersection should have only the things present in every version
+  (check "(print (unpack [_VERSION]))"
+         [{:message "unknown identifier: unpack"}]
+         [{:message "unknown identifier: _VERSION"}]
+         {:lua-version "intersection"}))
+
+{: test-lua-versions
+ : test-compile-error
  : test-parse-error
  : test-macro-error
  : test-multiple-errors}

test/utils/init.fnl

@@ -41,7 +41,7 @@
     (set result.text text)
     result))
 
-(fn create-client [file-contents ?opts]
+(fn create-client [file-contents ?opts ?config]
   ;; TODO big function, split up
   (let [opts (or ?opts {})
         (provide-root-uri file-contents) (if (= (type file-contents) :table)
@@ -81,6 +81,8 @@
                                  :jsonrpc "2.0"
                                  :method "initialize"
                                  : params})
+          _     (each [k v (pairs (or ?config []))]
+                  (tset server.configuration k v))
           [{:params {: diagnostics}}] (client:open-file! uri text)]
         {: client
          : server