sketch out global completion config setup

Author: zth

analysis/src/CompletionBackEnd.ml

@@ -1135,6 +1135,32 @@ and getCompletionsForContextPath ~debug ~full ~opens ~rawOpens ~pos ~env ~exact
                      | _ -> false
                    else true)
         in
+
+        (* TODO(config-complete-builtins) This config and config resolution should come from `package` instead. *)
+        let pretendPackageBuiltinsConfig =
+          Misc.StringMap.of_list
+            [("array", ["ArrayUtils"]); ("Fastify.t", ["FastifyExt"])]
+        in
+        let globallyConfiguredCompletionsForType =
+          match
+            pretendPackageBuiltinsConfig |> Misc.StringMap.find_opt mainTypeId
+          with
+          | None -> []
+          | Some completionPaths ->
+            completionPaths |> List.map (fun p -> String.split_on_char '.' p)
+        in
+
+        let globallyConfiguredCompletions =
+          globallyConfiguredCompletionsForType
+          |> List.map (fun completionPath ->
+                 completionsForPipeFromCompletionPath ~envCompletionIsMadeFrom
+                   ~opens ~pos ~scope ~debug ~prefix ~env ~rawOpens ~full
+                   completionPath)
+          |> List.flatten
+          |> TypeUtils.filterPipeableFunctions ~synthetic:true ~env ~full
+               ~targetTypeId:mainTypeId
+        in
+
         (* Extra completions can be drawn from the @editor.completeFrom attribute. Here we
            find and add those completions as well. *)
         let extraCompletions =
@@ -1154,7 +1180,8 @@ and getCompletionsForContextPath ~debug ~full ~opens ~rawOpens ~pos ~env ~exact
               ~full ~rawOpens typ
           else []
         in
-        jsxCompletions @ pipeCompletions @ extraCompletions))
+        jsxCompletions @ pipeCompletions @ extraCompletions
+        @ globallyConfiguredCompletions))
   | CTuple ctxPaths ->
     if Debug.verbose () then print_endline "[ctx_path]--> CTuple";
     (* Turn a list of context paths into a list of type expressions. *)

tests/analysis_tests/tests/src/ArrayUtils.res

@@ -0,0 +1 @@
+let empty = arr => Array.length(arr) === 0

tests/analysis_tests/tests/src/CompletionConfiguredBuiltins.res

@@ -0,0 +1,9 @@
+let x = [1, 2, 3]
+
+// x->em
+//      ^com
+
+external fastify: Fastify.t = "fastify"
+
+// fastify->doSt
+//              ^com

tests/analysis_tests/tests/src/Fastify.res

@@ -0,0 +1 @@
+type t

tests/analysis_tests/tests/src/FastifyExt.res

@@ -0,0 +1 @@
+let doStuff = (t: Fastify.t) => Console.log(t)

tests/analysis_tests/tests/src/expected/ArrayUtils.res.txt

@@ -0,0 +1,37 @@
+Complete src/CompletionConfiguredBuiltins.res 2:8
+posCursor:[2:8] posNoWhite:[2:7] Found expr:[2:3->2:8]
+Completable: Cpath Value[x]->em
+Package opens Stdlib.place holder Pervasives.JsxModules.place holder
+Resolved opens 1 Stdlib
+ContextPath Value[x]->em
+ContextPath Value[x]
+Path x
+Path Stdlib.Array.em
+Path ArrayUtils.em
+[{
+    "label": "ArrayUtils.empty",
+    "kind": 12,
+    "tags": [],
+    "detail": "array<'a> => bool",
+    "documentation": null
+  }]
+
+Complete src/CompletionConfiguredBuiltins.res 7:16
+posCursor:[7:16] posNoWhite:[7:15] Found expr:[7:3->7:16]
+Completable: Cpath Value[fastify]->doSt
+Package opens Stdlib.place holder Pervasives.JsxModules.place holder
+Resolved opens 1 Stdlib
+ContextPath Value[fastify]->doSt
+ContextPath Value[fastify]
+Path fastify
+CPPipe pathFromEnv:Fastify found:false
+Path Fastify.doSt
+Path FastifyExt.doSt
+[{
+    "label": "FastifyExt.doStuff",
+    "kind": 12,
+    "tags": [],
+    "detail": "Fastify.t => unit",
+    "documentation": null
+  }]
+

tests/analysis_tests/tests/src/expected/Completion.res.txt

@@ -415,6 +415,7 @@ ContextPath Value[String, split](Nolabel, Nolabel)
 ContextPath Value[String, split]
 Path String.split
 Path Stdlib.Array.ma
+Path ArrayUtils.ma
 [{
     "label": "Array.map",
     "kind": 12,

tests/analysis_tests/tests/src/expected/CompletionConfiguredBuiltins.res.txt

@@ -467,6 +467,7 @@ ContextPath Value[someArr]->a <<jsx>>
 ContextPath Value[someArr]
 Path someArr
 Path Stdlib.Array.a
+Path ArrayUtils.a
 [{
     "label": "React.array",
     "kind": 12,