illustrate new issue with pipe completion paths

Author: zth

analysis/src/CompletionBackEnd.ml

@@ -857,9 +857,14 @@ and getCompletionsForContextPath ~full ~opens ~rawOpens ~allFiles ~pos ~env
     with
     | None -> []
     | Some (typ, envFromCompletionItem) -> (
+      (* Passing `envFromCompletionItem` into `resolveTypeForPipeCompletion`
+         fixes the issue in `CompletionInferValues.res`, but breaks other pipe
+         chains. Change it and see what breaks instead. *)
       let env, typ =
         typ
-        |> TypeUtils.resolveTypeForPipeCompletion ~env ~package ~full ~lhsLoc
+        |> TypeUtils.resolveTypeForPipeCompletion
+           (* by doing this ~env:envFromCompletionItem*)
+             ~env ~package ~full ~lhsLoc
       in
       let completionPath =
         match typ with

analysis/tests/src/CompletionInferValues.res

@@ -154,3 +154,11 @@ let fn3 = (~cb: sameFileRecord => unit) => {
 // Handles pipe chains as input for switch
 // let x = 123; switch x->Belt.Int.toString->Js.String2.split("/") { | }
 //                                                                    ^com
+
+// Regular completion works
+// let renderer = CompletionSupport2.makeRenderer(~prepare=() => "hello",~render=({support}) => {support.},())
+//                                                                                                       ^com
+
+// But pipe completion gets the wrong completion path. Should be `ReactDOM.Client.Root.t`, but ends up being `CompletionSupport2.ReactDOM.Client.Root.t`.
+// let renderer = CompletionSupport2.makeRenderer(~prepare=() => "hello",~render=({support:{root}}) => {root->},())
+//                                                                                                            ^com

analysis/tests/src/CompletionSupport2.res

@@ -0,0 +1,17 @@
+module Internal = {
+  type prepareProps<'prepared> = {
+    someName: string,
+    support: CompletionSupport.Nested.config,
+    prepared: 'prepared,
+  }
+}
+
+let makeRenderer = (
+  ~prepare: unit => 'prepared,
+  ~render: Internal.prepareProps<'prepared> => React.element,
+  (),
+) => {
+  let _ = prepare
+  let _ = render
+  "123"
+}

analysis/tests/src/expected/CompletionInferValues.res.txt

@@ -508,3 +508,27 @@ Completable: Cpattern Value[Js, String2, split](Nolabel, Nolabel)
     "insertTextFormat": 2
   }]
 
+Complete src/CompletionInferValues.res 158:105
+posCursor:[158:105] posNoWhite:[158:104] Found expr:[158:18->158:110]
+Pexp_apply ...[158:18->158:49] (~prepare158:51->158:58=...[158:59->158:72], ~render158:74->158:80=...[158:81->158:106], ...[158:107->158:109])
+posCursor:[158:105] posNoWhite:[158:104] Found expr:[158:81->158:106]
+posCursor:[158:105] posNoWhite:[158:104] Found expr:[158:97->158:105]
+Pexp_field [158:97->158:104] _:[158:105->158:105]
+Completable: Cpath Value[support].""
+[{
+    "label": "root",
+    "kind": 5,
+    "tags": [],
+    "detail": "root: ReactDOM.Client.Root.t\n\ntype config = {root: ReactDOM.Client.Root.t}",
+    "documentation": null
+  }]
+
+Complete src/CompletionInferValues.res 162:110
+posCursor:[162:110] posNoWhite:[162:109] Found expr:[162:18->162:115]
+Pexp_apply ...[162:18->162:49] (~prepare162:51->162:58=...[162:59->162:72], ~render162:74->162:80=...[162:81->162:111], ...[162:112->162:114])
+posCursor:[162:110] posNoWhite:[162:109] Found expr:[162:81->162:111]
+posCursor:[162:110] posNoWhite:[162:109] Found expr:[162:104->0:-1]
+posCursor:[162:110] posNoWhite:[162:109] Found expr:[162:104->0:-1]
+Completable: Cpath Value[root]->
+[]
+