Better completion for applications (#7291)

* WIP: better completion for applications

* Comment out scope thing

* Uncomment filter

* Remove verbose

* Optional dig

* Add changelog entry

Author: nojaf

CHANGELOG.md

@@ -35,6 +35,7 @@
 - Stdlib namespace for Core modules (fixes name clashes with user modules). https://github.com/rescript-lang/rescript/pull/7285
 - Fix runtime type check for Object in untagged variants when one variant case is `null`. https://github.com/rescript-lang/rescript/pull/7303
 - Fix files that were being truncated when sent to the CDN over FTP. https://github.com/rescript-lang/rescript/pull/7306
+- Fix better editor completion for applications. https://github.com/rescript-lang/rescript/pull/7291
 
 #### :house: Internal
 

analysis/src/CompletionBackEnd.ml

@@ -965,7 +965,8 @@ and getCompletionsForContextPath ~debug ~full ~opens ~rawOpens ~pos ~env ~exact
         | [], [(Nolabel | Labelled _ | Optional _)] ->
           (* should not happen, but just ignore extra arguments *) []
       in
-      match TypeUtils.extractFunctionType ~env ~package typ with
+
+      match TypeUtils.extractFunctionType ~env ~package ~digInto:false typ with
       | args, tRet when args <> [] ->
         let args = processApply args labels in
         let retType = reconstructFunctionType args tRet in

analysis/src/TypeUtils.ml

@@ -243,12 +243,12 @@ let rec extractObjectType ~env ~package (t : Types.type_expr) =
     | _ -> None)
   | _ -> None
 
-let extractFunctionType ~env ~package typ =
+let extractFunctionType ~env ~package ?(digInto = true) typ =
   let rec loop ~env acc (t : Types.type_expr) =
     match t.desc with
     | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> loop ~env acc t1
     | Tarrow (label, tArg, tRet, _, _) -> loop ~env ((label, tArg) :: acc) tRet
-    | Tconstr (path, typeArgs, _) -> (
+    | Tconstr (path, typeArgs, _) when digInto -> (
       match References.digConstructor ~env ~package path with
       | Some
           ( env,

tests/analysis_tests/tests/src/CompletionTaggedTemplate.res

@@ -1,5 +1,5 @@
 module M = {
-    type t
+    type t = promise<string>
 
     let a = (_t:t) => 4
     let b = (_:t) => "c"
@@ -9,8 +9,10 @@ module M = {
 @module("meh") @taggedTemplate
 external meh: (array<string>, array<string>) => M.t = "default"
 
+let w = meh``
+
+// let _ = w.
+//           ^com
+
 // let x = meh`foo`.
 //                  ^com
-
-// let y = meh`bar`.x
-//                   ^com

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

@@ -1841,13 +1841,19 @@ Resolved opens 3 Stdlib Completion Completion
 ContextPath Value[withCallback](~a)
 ContextPath Value[withCallback]
 Path withCallback
-Found type for function (~b: int) => int
+Found type for function (~b: int) => callback
 [{
     "label": "b",
     "kind": 4,
     "tags": [],
     "detail": "int",
     "documentation": null
+  }, {
+    "label": "a",
+    "kind": 4,
+    "tags": [],
+    "detail": "int",
+    "documentation": null
   }]
 
 Complete src/Completion.res 332:21
@@ -1860,7 +1866,7 @@ Resolved opens 3 Stdlib Completion Completion
 ContextPath Value[withCallback](~b)
 ContextPath Value[withCallback]
 Path withCallback
-Found type for function (~a: int) => int
+Found type for function callback
 [{
     "label": "a",
     "kind": 4,

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

@@ -1,16 +1,15 @@
-Complete src/CompletionTaggedTemplate.res 11:20
-posCursor:[11:20] posNoWhite:[11:19] Found expr:[11:11->0:-1]
-Completable: Cpath Value[meh](Nolabel, Nolabel).""
+Complete src/CompletionTaggedTemplate.res 13:13
+posCursor:[13:13] posNoWhite:[13:12] Found expr:[13:11->13:13]
+Pexp_field [13:11->13:12] _:[19:0->13:13]
+Completable: Cpath Value[w].""
 Package opens Stdlib.place holder Pervasives.JsxModules.place holder
 Resolved opens 1 Stdlib
-ContextPath Value[meh](Nolabel, Nolabel).""
-ContextPath Value[meh](Nolabel, Nolabel)
-ContextPath Value[meh]
-Path meh
-ContextPath Value[meh](Nolabel, Nolabel, Nolabel)->
-ContextPath Value[meh](Nolabel, Nolabel, Nolabel)
-ContextPath Value[meh]
-Path meh
+ContextPath Value[w].""
+ContextPath Value[w]
+Path w
+ContextPath Value[w]->
+ContextPath Value[w]
+Path w
 CPPipe pathFromEnv:M found:true
 Path M.
 [{
@@ -22,7 +21,7 @@ Path M.
     "sortText": "xyz",
     "insertText": "->M.xyz",
     "additionalTextEdits": [{
-      "range": {"start": {"line": 11, "character": 19}, "end": {"line": 11, "character": 20}},
+      "range": {"start": {"line": 13, "character": 12}, "end": {"line": 13, "character": 13}},
       "newText": ""
       }]
   }, {
@@ -34,7 +33,7 @@ Path M.
     "sortText": "b",
     "insertText": "->M.b",
     "additionalTextEdits": [{
-      "range": {"start": {"line": 11, "character": 19}, "end": {"line": 11, "character": 20}},
+      "range": {"start": {"line": 13, "character": 12}, "end": {"line": 13, "character": 13}},
       "newText": ""
       }]
   }, {
@@ -46,26 +45,26 @@ Path M.
     "sortText": "a",
     "insertText": "->M.a",
     "additionalTextEdits": [{
-      "range": {"start": {"line": 11, "character": 19}, "end": {"line": 11, "character": 20}},
+      "range": {"start": {"line": 13, "character": 12}, "end": {"line": 13, "character": 13}},
       "newText": ""
       }]
   }]
 
-Complete src/CompletionTaggedTemplate.res 14:21
-posCursor:[14:21] posNoWhite:[14:20] Found expr:[14:11->14:21]
-Completable: Cpath Value[meh](Nolabel, Nolabel).x
+Complete src/CompletionTaggedTemplate.res 16:20
+posCursor:[16:20] posNoWhite:[16:19] Found expr:[16:11->0:-1]
+Completable: Cpath Value[meh](Nolabel, Nolabel).""
 Package opens Stdlib.place holder Pervasives.JsxModules.place holder
 Resolved opens 1 Stdlib
-ContextPath Value[meh](Nolabel, Nolabel).x
+ContextPath Value[meh](Nolabel, Nolabel).""
 ContextPath Value[meh](Nolabel, Nolabel)
 ContextPath Value[meh]
 Path meh
-ContextPath Value[meh](Nolabel, Nolabel, Nolabel)->x
+ContextPath Value[meh](Nolabel, Nolabel, Nolabel)->
 ContextPath Value[meh](Nolabel, Nolabel, Nolabel)
 ContextPath Value[meh]
 Path meh
 CPPipe pathFromEnv:M found:true
-Path M.x
+Path M.
 [{
     "label": "->M.xyz",
     "kind": 12,
@@ -75,7 +74,31 @@ Path M.x
     "sortText": "xyz",
     "insertText": "->M.xyz",
     "additionalTextEdits": [{
-      "range": {"start": {"line": 14, "character": 19}, "end": {"line": 14, "character": 20}},
+      "range": {"start": {"line": 16, "character": 19}, "end": {"line": 16, "character": 20}},
+      "newText": ""
+      }]
+  }, {
+    "label": "->M.b",
+    "kind": 12,
+    "tags": [],
+    "detail": "t => string",
+    "documentation": null,
+    "sortText": "b",
+    "insertText": "->M.b",
+    "additionalTextEdits": [{
+      "range": {"start": {"line": 16, "character": 19}, "end": {"line": 16, "character": 20}},
+      "newText": ""
+      }]
+  }, {
+    "label": "->M.a",
+    "kind": 12,
+    "tags": [],
+    "detail": "t => int",
+    "documentation": null,
+    "sortText": "a",
+    "insertText": "->M.a",
+    "additionalTextEdits": [{
+      "range": {"start": {"line": 16, "character": 19}, "end": {"line": 16, "character": 20}},
       "newText": ""
       }]
   }]