fix "unknown module field" when accessing fields from doc objects with no known fields

this means stuff like `io.stderr:write` isn't a warning anymore

src/fennel-ls/analyzer.fnl

@@ -65,14 +65,16 @@ find the definition `10`, but if `opts.stop-early?` is set, it would find
   (stack-add-split! stack (utils.multi-sym-split symbol)))
 
 (λ search-document [server document stack opts]
-  (when (and (not= (tostring (?. document :binding)) :_G)
-             (= (length stack) 1))
+  (when (not= (tostring (?. document :binding)) :_G)
     (set opts.searched-through-require-with-stack-size-1 true))
   (if (= 0 (length stack))
     document
     (and document.fields
          (. document.fields (. stack (length stack))))
-    (search-document server (. document.fields (table.remove stack)) stack opts)))
+    (search-document server (. document.fields (table.remove stack)) stack opts)
+    (not document.fields)
+    (do
+      (set opts.searched-through-require-indeterminate true))))
 
 (λ search-val [server file ?ast stack opts]
   "searches for the definition of the ast, adjusted to 1 value"

src/fennel-ls/lint.fnl

@@ -46,7 +46,9 @@ the `file.diagnostics` field, filling it with diagnostics."
   "if ?ast is a module field that isn't known, return a diagnostic"
   (let [opts {}
         item (analyzer.search-ast server file ?ast stack opts)]
-    (if (and (not item) opts.searched-through-require-with-stack-size-1)
+    (if (and (not item)
+             opts.searched-through-require-with-stack-size-1
+             (not opts.searched-through-require-indeterminate))
       {:range (message.ast->range server file symbol)
        :message (.. "unknown field: " (tostring symbol))
        :severity message.severity.WARN

test/init.fnl

@@ -3,7 +3,8 @@
 
 (case (os.getenv "FAITH_TEST")
   target (let [(module function) (target:match "([^ ]+) ([^ ]+)")]
-            (xpcall (. (require module) function) #(print ($:tostring target))))
+           (tset package.loaded module {function (. (require module) function)})
+           (faith.run [module]))
   _ (faith.run
       [:test.json-rpc
        :test.string-processing

test/lint.fnl

@@ -110,6 +110,9 @@
                      field.unknown"}
          []
          [{:code 302}])
+  (check "package.loaded.mymodule io.stderr.write"
+         []
+         [{:code 302}])
   nil)
 
 (fn test-unnecessary-colon []