pipe complete only for functions that take the expected type as the first argument

Author: zth

analysis/src/CompletionBackEnd.ml

@@ -1113,6 +1113,7 @@ and getCompletionsForContextPath ~debug ~full ~opens ~rawOpens ~pos ~env ~exact
         TypeUtils.getExtraModuleToCompleteFromForType typ
           ~env:envFromCompletionItem ~full
       in
+      let tPath = TypeUtils.pathFromTypeExpr typ in
       let env, typ =
         typ
         |> TypeUtils.resolveTypeForPipeCompletion ~env ~package ~full ~lhsLoc
@@ -1123,10 +1124,6 @@ and getCompletionsForContextPath ~debug ~full ~opens ~rawOpens ~pos ~env ~exact
             (QueryEnv.toString env)
             (QueryEnv.toString envFromCompletionItem)
         else Printf.printf "CPPipe env:%s\n" (QueryEnv.toString env);
-      let tPath =
-        match typ with
-        | Builtin (_, t) | TypExpr t -> TypeUtils.pathFromTypeExpr t
-      in
       let completionPath =
         match typ with
         | Builtin (builtin, _) ->

analysis/src/TypeUtils.ml

@@ -1172,7 +1172,16 @@ let rec fnTakesTypeAsFirstArg ~env ~full ~path t =
       let p = pathFromTypeExpr t in
       match p with
       | None -> false
-      | Some p -> Path.same p path || Path.name p = "t")
+      | Some p ->
+        (*
+           Rules:
+           - The path p of the current type in the module we're looking at is relative to the current module.
+           - The path we're comparing against, `path`, is assumed to belong to this current module, because we're completing from it.
+
+           Therefore, we can safely pluck out just the last part of the `path`, but need to use the entire name of the current type
+           we're comparing with.
+        *)
+        Path.name p = Path.last path || Path.name p = "t")
     | _ -> false)
   | _ -> false
 

analysis/tests/src/CompletionPipeChain.res

@@ -103,3 +103,12 @@ let r = %re("/t/g")
 
 // r->la
 //      ^com
+
+module Xyz = {
+  type xx = One
+  let do = (_: xx) => ""
+}
+
+let xx = Xyz.One
+// xx->
+//     ^com

analysis/tests/src/CompletionPipeSubmodules.res

@@ -1,14 +1,13 @@
 module A = {
   module B1 = {
     type b1 = B1
-    type t = b1 // TODO(pipe-filter) Should be allowed without needing type t
     let xx = B1
-    let d = (_: t) => ""
+    let d = (_: b1) => ""
   }
   module B2 = {
     let yy = 20
   }
-  type t = {v: B1.t} // TODO(pipe-filter) Should be allowed without needing type t
+  type t2 = {v: B1.b1}
   let x = {v: B1.B1}
 }
 
@@ -28,8 +27,7 @@ module C = {
 module D = {
   module C2 = {
     type t2 = C2
-    type t = t2 // TODO(pipe-filter) Should be allowed without needing type t
-    let do = (_: t) => ""
+    let do = (_: t2) => ""
   }
 
   type d = {v: C.t, v2: C2.t2}

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

@@ -501,3 +501,23 @@ Path Js.Re.la
     "documentation": {"kind": "markdown", "value": "\nReturns the index where the next match will start its search. This property\nwill be modified when the RegExp object is used, if the global (\"g\") flag is\nset.\n\n## Examples\n\n```rescript\nlet re = %re(\"/ab*TODO/g\")\nlet str = \"abbcdefabh\"\n\nlet break = ref(false)\nwhile !break.contents {\n  switch Js.Re.exec_(re, str) {\n  | Some(result) => Js.Nullable.iter(Js.Re.captures(result)[0], (. match_) => {\n      let next = Belt.Int.toString(Js.Re.lastIndex(re))\n      Js.log(\"Found \" ++ (match_ ++ (\". Next match starts at \" ++ next)))\n    })\n  | None => break := true\n  }\n}\n```\n\nSee\n[`RegExp: lastIndex`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/lastIndex)\non MDN.\n"}
   }]
 
+Complete src/CompletionPipeChain.res 112:7
+posCursor:[112:7] posNoWhite:[112:6] Found expr:[112:3->0:-1]
+Completable: Cpath Value[xx]->
+Package opens Pervasives.JsxModules.place holder
+Resolved opens 1 pervasives
+ContextPath Value[xx]->
+ContextPath Value[xx]
+Path xx
+CPPipe env:CompletionPipeChain
+CPPipe type path:Xyz.xx
+CPPipe pathFromEnv:Xyz found:true
+Path Xyz.
+[{
+    "label": "Xyz.do",
+    "kind": 12,
+    "tags": [],
+    "detail": "xx => string",
+    "documentation": null
+  }]
+

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

@@ -1,5 +1,5 @@
-Complete src/CompletionPipeSubmodules.res 14:20
-posCursor:[14:20] posNoWhite:[14:19] Found expr:[14:11->22:8]
+Complete src/CompletionPipeSubmodules.res 13:20
+posCursor:[13:20] posNoWhite:[13:19] Found expr:[13:11->21:8]
 Completable: Cpath Value[A, B1, xx]->
 Package opens Pervasives.JsxModules.place holder
 Resolved opens 1 pervasives
@@ -14,34 +14,33 @@ Path A.B1.
     "label": "A.B1.d",
     "kind": 12,
     "tags": [],
-    "detail": "t => string",
+    "detail": "b1 => string",
     "documentation": null
   }]
 
-Complete src/CompletionPipeSubmodules.res 18:18
-posCursor:[18:18] posNoWhite:[18:17] Found expr:[18:11->22:8]
+Complete src/CompletionPipeSubmodules.res 17:18
+posCursor:[17:18] posNoWhite:[17:17] Found expr:[17:11->21:8]
 Completable: Cpath Value[A, x].v->
 Package opens Pervasives.JsxModules.place holder
 Resolved opens 1 pervasives
 ContextPath Value[A, x].v->
 ContextPath Value[A, x].v
 ContextPath Value[A, x]
 Path A.x
-Path v
 CPPipe env:CompletionPipeSubmodules envFromCompletionItem:CompletionPipeSubmodules.A
-CPPipe type path:B1.t
+CPPipe type path:B1.b1
 CPPipe pathFromEnv:A.B1 found:true
 Path A.B1.
 [{
     "label": "A.B1.d",
     "kind": 12,
     "tags": [],
-    "detail": "t => string",
+    "detail": "b1 => string",
     "documentation": null
   }]
 
-Complete src/CompletionPipeSubmodules.res 43:20
-posCursor:[43:20] posNoWhite:[43:19] Found expr:[43:11->0:-1]
+Complete src/CompletionPipeSubmodules.res 41:20
+posCursor:[41:20] posNoWhite:[41:19] Found expr:[41:11->0:-1]
 Completable: Cpath Value[E, e].v.v->
 Package opens Pervasives.JsxModules.place holder
 Resolved opens 1 pervasives
@@ -62,8 +61,8 @@ Path C.
     "documentation": null
   }]
 
-Complete src/CompletionPipeSubmodules.res 47:21
-posCursor:[47:21] posNoWhite:[47:20] Found expr:[47:11->0:-1]
+Complete src/CompletionPipeSubmodules.res 45:21
+posCursor:[45:21] posNoWhite:[45:20] Found expr:[45:11->0:-1]
 Completable: Cpath Value[E, e].v.v2->
 Package opens Pervasives.JsxModules.place holder
 Resolved opens 1 pervasives
@@ -80,7 +79,7 @@ Path D.C2.
     "label": "D.C2.do",
     "kind": 12,
     "tags": [],
-    "detail": "t => string",
+    "detail": "t2 => string",
     "documentation": null
   }]