More removal of _ in expr completion (#890)

* more removal of _ in expr completion

* changelog

Author: zth

CHANGELOG.md

@@ -12,6 +12,10 @@
 
 ## master
 
+#### :nail_care: Polish
+
+- More cases of not emitting `_` when completing in expressions. https://github.com/rescript-lang/rescript-vscode/pull/890
+
 ## 1.34.0
 
 #### :rocket: New Feature
@@ -23,7 +27,7 @@
 #### :nail_care: Polish
 
 - Better error recovery when analysis fails. https://github.com/rescript-lang/rescript-vscode/pull/880
-- Do not emit `_` when completing in patterns. https://github.com/rescript-lang/rescript-vscode/pull/885
+- Do not emit `_` when completing in expressions. https://github.com/rescript-lang/rescript-vscode/pull/885
 - Include fields when completing a braced expr that's an ID, where it the path likely starts with a module. https://github.com/rescript-lang/rescript-vscode/pull/882
 
 ## 1.32.0

analysis/src/CompletionBackEnd.ml

@@ -1168,24 +1168,32 @@ let filterItems items ~prefix =
     |> List.filter (fun (item : Completion.t) ->
            Utils.startsWith item.name prefix)
 
-let printConstructorArgs argsLen ~asSnippet =
+type completionMode = Pattern of Completable.patternMode | Expression
+
+let emptyCase ~mode num =
+  match mode with
+  | Expression -> "$" ^ string_of_int (num - 1)
+  | Pattern _ -> "${" ^ string_of_int num ^ ":_}"
+
+let printConstructorArgs ~mode ~asSnippet argsLen =
   let args = ref [] in
   for argNum = 1 to argsLen do
     args :=
-      !args @ [(if asSnippet then Printf.sprintf "${%i:_}" argNum else "_")]
+      !args
+      @ [
+          (match (asSnippet, argsLen) with
+          | true, l when l > 1 -> Printf.sprintf "${%i:_}" argNum
+          | true, l when l > 0 -> emptyCase ~mode argNum
+          | _ -> "_");
+        ]
   done;
   if List.length !args > 0 then "(" ^ (!args |> String.concat ", ") ^ ")"
   else ""
 
-type completionMode = Pattern of Completable.patternMode | Expression
-
 let rec completeTypedValue ~rawOpens ~full ~prefix ~completionContext ~mode
     (t : SharedTypes.completionType) =
-  let emptyCase num =
-    match mode with
-    | Expression -> "$" ^ string_of_int (num - 1)
-    | Pattern _ -> "${" ^ string_of_int num ^ ":_}"
-  in
+  let emptyCase = emptyCase ~mode in
+  let printConstructorArgs = printConstructorArgs ~mode in
   match t with
   | TtypeT {env; path} ->
     (* Find all functions in the module that returns type t *)

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

@@ -1163,7 +1163,7 @@ Path fnTakingPolyVariant
     "tags": [],
     "detail": "#two(bool)\n\n[#one | #three(someRecord, bool) | #two(bool)]",
     "documentation": null,
-    "insertText": "#two(${1:_})",
+    "insertText": "#two($0)",
     "insertTextFormat": 2
   }]
 
@@ -1198,7 +1198,7 @@ Path fnTakingPolyVariant
     "tags": [],
     "detail": "#two(bool)\n\n[#one | #three(someRecord, bool) | #two(bool)]",
     "documentation": null,
-    "insertText": "two(${1:_})",
+    "insertText": "two($0)",
     "insertTextFormat": 2
   }]
 

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

@@ -60,7 +60,7 @@ Path CompletionSupport.TestComponent.make
     "detail": "Three(int)\n\ntype testVariant = One | Two | Three(int)",
     "documentation": null,
     "sortText": "A Three(_)",
-    "insertText": "{Three(${1:_})}",
+    "insertText": "{Three($0)}",
     "insertTextFormat": 2
   }, {
     "label": "TableclothMap",
@@ -250,7 +250,7 @@ Path CompletionSupport.TestComponent.make
     "tags": [],
     "detail": "Three(int)\n\ntype testVariant = One | Two | Three(int)",
     "documentation": null,
-    "insertText": "Three(${1:_})",
+    "insertText": "Three($0)",
     "insertTextFormat": 2
   }]
 

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

@@ -58,7 +58,7 @@ Path someVariant
     "tags": [],
     "detail": "Two(bool)\n\ntype someVariant = One | Two(bool)",
     "documentation": null,
-    "insertText": "Two(${1:_})",
+    "insertText": "Two($0)",
     "insertTextFormat": 2
   }]
 
@@ -113,7 +113,7 @@ Path somePolyVariant
     "tags": [],
     "detail": "#two(bool)\n\n[#one | #two(bool)]",
     "documentation": null,
-    "insertText": "#two(${1:_})",
+    "insertText": "#two($0)",
     "insertTextFormat": 2
   }]
 
@@ -240,7 +240,7 @@ Path someVariant
     "tags": [],
     "detail": "Two(bool)\n\ntype someVariant = One | Two(bool)",
     "documentation": null,
-    "insertText": "Some(Two(${1:_}))",
+    "insertText": "Some(Two($0))",
     "insertTextFormat": 2
   }]
 
@@ -266,7 +266,7 @@ Path someVariant
     "tags": [],
     "detail": "Two(bool)\n\ntype someVariant = One | Two(bool)",
     "documentation": null,
-    "insertText": "Two(${1:_})",
+    "insertText": "Two($0)",
     "insertTextFormat": 2
   }]
 
@@ -311,7 +311,7 @@ Path someVariant
     "tags": [],
     "detail": "Two(bool)\n\ntype someVariant = One | Two(bool)",
     "documentation": null,
-    "insertText": "Two(${1:_})",
+    "insertText": "Two($0)",
     "insertTextFormat": 2
   }]
 
@@ -358,7 +358,7 @@ Path someVariant
     "tags": [],
     "detail": "Two(bool)\n\ntype someVariant = One | Two(bool)",
     "documentation": null,
-    "insertText": "Two(${1:_})",
+    "insertText": "Two($0)",
     "insertTextFormat": 2
   }]