Show type when hovering on JSX props.

Fixes #314

Author: cristianoc

analysis/src/Cli.ml

@@ -70,16 +70,17 @@ let main () =
   | [_; "completion"; path; line; col; currentFile] ->
     Commands.completion ~debug:false ~path
       ~pos:(int_of_string line, int_of_string col)
-      ~currentFile ~forHover:false
+      ~currentFile
   | [_; "definition"; path; line; col] ->
     Commands.definition ~path ~line:(int_of_string line)
       ~col:(int_of_string col)
   | [_; "typeDefinition"; path; line; col] ->
     Commands.typeDefinition ~path ~line:(int_of_string line)
       ~col:(int_of_string col)
   | [_; "documentSymbol"; path] -> DocumentSymbol.command ~path
-  | [_; "hover"; path; line; col] ->
+  | [_; "hover"; path; line; col; currentFile] ->
     Commands.hover ~path ~line:(int_of_string line) ~col:(int_of_string col)
+      ~currentFile ~debug:false
   | [_; "codeAction"; path; line; col; currentFile] ->
     Commands.codeAction ~path ~line:(int_of_string line)
       ~col:(int_of_string col) ~currentFile

analysis/src/Commands.ml

@@ -1,41 +1,49 @@
-let completion ~debug ~path ~pos ~currentFile ~forHover =
-  let result =
-    let textOpt = Files.readFile currentFile in
-    match textOpt with
-    | None | Some "" -> []
-    | Some text ->
-      let completions =
-        match
-          CompletionFrontEnd.completionWithParser ~debug ~path ~posCursor:pos
-            ~currentFile ~text
-        with
-        | None -> []
-        | Some (completable, scope) -> (
-          if debug then
-            Printf.printf "Completable: %s\n"
-              (SharedTypes.Completable.toString completable);
-          (* Only perform expensive ast operations if there are completables *)
-          match Cmt.fromPath ~path with
-          | None -> []
-          | Some full ->
-            let env = SharedTypes.QueryEnv.fromFile full.file in
-            let package = full.package in
-            completable
-            |> CompletionBackEnd.processCompletable ~debug ~package ~pos ~scope
-                 ~env ~forHover)
-      in
-      completions |> List.map CompletionBackEnd.completionToItem
-  in
+let getCompletions ~debug ~path ~pos ~currentFile ~forHover =
+  let textOpt = Files.readFile currentFile in
+  match textOpt with
+  | None | Some "" -> []
+  | Some text -> (
+    match
+      CompletionFrontEnd.completionWithParser ~debug ~path ~posCursor:pos
+        ~currentFile ~text
+    with
+    | None -> []
+    | Some (completable, scope) -> (
+      if debug then
+        Printf.printf "Completable: %s\n"
+          (SharedTypes.Completable.toString completable);
+      (* Only perform expensive ast operations if there are completables *)
+      match Cmt.fromPath ~path with
+      | None -> []
+      | Some full ->
+        let env = SharedTypes.QueryEnv.fromFile full.file in
+        let package = full.package in
+        completable
+        |> CompletionBackEnd.processCompletable ~debug ~package ~pos ~scope ~env
+             ~forHover))
+
+let completion ~debug ~path ~pos ~currentFile =
   print_endline
-    (result |> List.map Protocol.stringifyCompletionItem |> Protocol.array)
+    (getCompletions ~debug ~path ~pos ~currentFile ~forHover:false
+    |> List.map CompletionBackEnd.completionToItem
+    |> List.map Protocol.stringifyCompletionItem
+    |> Protocol.array)
 
-let hover ~path ~line ~col =
+let hover ~path ~line ~col ~currentFile ~debug =
   let result =
     match Cmt.fromPath ~path with
     | None -> Protocol.null
     | Some ({file} as full) -> (
       match References.getLocItem ~full ~line ~col with
-      | None -> Protocol.null
+      | None -> (
+        let completions =
+          getCompletions ~debug ~path ~pos:(line, col) ~currentFile
+            ~forHover:true
+        in
+        match completions with
+        | {kind = Label typString} :: _ ->
+          Protocol.stringifyHover {contents = Hover.codeBlock typString}
+        | _ -> Protocol.null)
       | Some locItem -> (
         let isModule =
           match locItem.locType with
@@ -273,7 +281,7 @@ let test ~path =
             print_endline
               ("Hover " ^ path ^ " " ^ string_of_int line ^ ":"
              ^ string_of_int col);
-            hover ~path ~line ~col
+            hover ~path ~line ~col ~currentFile:path ~debug:true
           | "ref" ->
             print_endline
               ("References " ^ path ^ " " ^ string_of_int line ^ ":"
@@ -316,8 +324,7 @@ let test ~path =
                    in
                    Printf.fprintf cout "%s\n" lineToOutput);
             close_out cout;
-            completion ~debug:true ~path ~pos:(line, col) ~currentFile
-              ~forHover:false;
+            completion ~debug:true ~path ~pos:(line, col) ~currentFile;
             Sys.remove currentFile
           | "hig" ->
             print_endline ("Highlight " ^ path);

analysis/src/CompletionBackEnd.ml

@@ -1328,7 +1328,7 @@ let processCompletable ~debug ~package ~scope ~env ~pos ~forHover
   | Cpath contextPath ->
     contextPath
     |> getCompletionsForContextPath ~package ~opens ~rawOpens ~allFiles ~pos
-         ~env ~exact:false ~scope
+         ~env ~exact:forHover ~scope
   | Cjsx ([id], prefix, identsSeen) when String.uncapitalize_ascii id = id ->
     let mkLabel (name, typString) =
       Completion.create ~name ~kind:(Label typString) ~env
@@ -1338,7 +1338,8 @@ let processCompletable ~debug ~package ~scope ~env ~pos ~forHover
     in
     (domLabels
     |> List.filter (fun (name, _t) ->
-           Utils.startsWith name prefix && not (List.mem name identsSeen))
+           Utils.startsWith name prefix
+           && (forHover || not (List.mem name identsSeen)))
     |> List.map mkLabel)
     @ keyLabels
   | Cjsx (componentPath, prefix, identsSeen) ->

analysis/src/CompletionFrontEnd.ml

@@ -211,7 +211,7 @@ let rec exprToContextPath (e : Parsetree.expression) =
     | Some contexPath -> Some (CPApply (contexPath, args |> List.map fst)))
   | _ -> None
 
-let completionWithParser ~debug ~path ~posCursor ~currentFile ~text =
+let completionWithParser ~debug ~path ~posCursor ~currentFile ~text  =
   let offset =
     match positionToOffset text posCursor with
     | Some offset -> offset

analysis/tests/src/Completion.res

@@ -342,4 +342,7 @@ let _ =
   </div>
 
 //let _ = switch Some(3) { | Some(thisIsNotSaved) -> this
-//                                                       ^com
+//                                                       ^com
+
+let _ = <div name="" />
+//            ^hov

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

@@ -1307,8 +1307,9 @@ Found type for function (~a: int) => int
   }]
 
 Complete tests/src/Completion.res 336:26
-posCursor:[336:26] posNoWhite:[336:25] Found expr:[333:3->341:8]
-JSX <div:[333:3->333:6] onClick[334:4->334:11]=...[334:13->0:-1]> _children:None
+posCursor:[336:26] posNoWhite:[336:25] Found expr:[333:3->346:23]
+JSX <div:[333:3->333:6] onClick[334:4->334:11]=...[334:13->346:23]> _children:None
+posCursor:[336:26] posNoWhite:[336:25] Found expr:[334:13->346:23]
 posCursor:[336:26] posNoWhite:[336:25] Found expr:[334:13->338:6]
 posCursor:[336:26] posNoWhite:[336:25] Found expr:[335:6->338:5]
 posCursor:[336:26] posNoWhite:[336:25] Found expr:[336:16->338:5]
@@ -1330,7 +1331,8 @@ Completable: Cpath Type[Res]
   }]
 
 Complete tests/src/Completion.res 343:57
-posCursor:[343:57] posNoWhite:[343:56] Found expr:[343:10->343:57]
+posCursor:[343:57] posNoWhite:[343:56] Found expr:[343:10->346:23]
+posCursor:[343:57] posNoWhite:[343:56] Found expr:[343:53->346:23]
 posCursor:[343:57] posNoWhite:[343:56] Found expr:[343:53->343:57]
 Pexp_ident this:[343:53->343:57]
 Completable: Cpath Value[this]
@@ -1342,3 +1344,9 @@ Completable: Cpath Value[this]
     "documentation": null
   }]
 
+Hover tests/src/Completion.res 346:14
+posCursor:[346:14] posNoWhite:[346:13] Found expr:[346:9->346:23]
+JSX <div:[346:9->346:12] name[346:13->346:17]=...[346:18->346:20]> _children:346:21
+Completable: Cjsx([div], name, [name])
+{"contents": "```rescript\nstring\n```"}
+

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

@@ -2,5 +2,12 @@ Hover tests/src/Fragment.res 6:19
 {"contents": "```rescript\nReact.component<{\"children\": React.element}>\n```\n\n```rescript\ntype component<'props> = componentLike<'props, element>\n```"}
 
 Hover tests/src/Fragment.res 9:56
+posCursor:[9:56] posNoWhite:[9:55] Found expr:[9:10->9:67]
+Pexp_construct :::[9:13->9:67] [9:13->9:67]
+posCursor:[9:56] posNoWhite:[9:55] Found expr:[9:13->9:67]
+posCursor:[9:56] posNoWhite:[9:55] Found expr:[9:13->9:66]
+JSX <SectionHeader:[9:13->9:26] > _children:9:26
+posCursor:[9:56] posNoWhite:[9:55] Found expr:__ghost__[9:10->9:67]
+Pexp_construct []:__ghost__[9:10->9:67] None
 null
 

server/src/server.ts

@@ -271,11 +271,30 @@ if (process.argv.includes("--stdio")) {
 function hover(msg: p.RequestMessage) {
   let params = msg.params as p.HoverParams;
   let filePath = fileURLToPath(params.textDocument.uri);
+  let extension = path.extname(params.textDocument.uri);
+  if (extension !== c.resExt && extension !== c.resiExt) {
+    // Can be called on renamed extension after rename
+    return {
+      jsonrpc: c.jsonrpcVersion,
+      id: msg.id,
+      result: null,
+    };
+  }
+  let code = getOpenedFileContent(params.textDocument.uri);
+  let tmpname = utils.createFileInTempDir();
+  fs.writeFileSync(tmpname, code, { encoding: "utf-8" });
   let response = utils.runAnalysisCommand(
     filePath,
-    ["hover", filePath, params.position.line, params.position.character],
+    [
+      "hover",
+      filePath,
+      params.position.line,
+      params.position.character,
+      tmpname,
+    ],
     msg
   );
+  fs.unlink(tmpname, () => null);
   return response;
 }