[WIP] Completion revamping

package.json

@@ -206,6 +206,11 @@
           ],
           "default": null,
           "description": "Path to the directory where platform-specific ReScript binaries are. You can use it if you haven't or don't want to use the installed ReScript from node_modules in your project."
+        },
+        "rescript.settings.newCompletion": {
+          "type": "boolean",
+          "default": false,
+          "description": "(experimental) Enable new completion engine"
         }
       }
     },

server/src/config.ts

@@ -11,6 +11,7 @@ export interface extensionConfiguration {
   codeLens?: boolean;
   binaryPath?: string | null;
   platformPath?: string | null;
+  newCompletion?: boolean;
   signatureHelp?: {
     enabled?: boolean;
     forConstructorPayloads?: boolean;
@@ -39,6 +40,7 @@ let config: { extensionConfiguration: extensionConfiguration } = {
     codeLens: false,
     binaryPath: null,
     platformPath: null,
+    newCompletion: false,
     signatureHelp: {
       enabled: true,
       forConstructorPayloads: true,

server/src/incrementalCompilation.ts

@@ -370,7 +370,7 @@ function removeAnsiCodes(s: string): string {
   const ansiEscape = /\x1B[@-_][0-?]*[ -/]*[@-~]/g;
   return s.replace(ansiEscape, "");
 }
-function triggerIncrementalCompilationOfFile(
+export function triggerIncrementalCompilationOfFile(
   filePath: string,
   fileContent: string,
   send: send,
@@ -469,9 +469,10 @@ function triggerIncrementalCompilationOfFile(
     entry.killCompilationListeners = [];
   }
   const triggerToken = performance.now();
+  // TODO: Can we remove this timeout? Don't remember why it was added...
   const timeout = setTimeout(() => {
     compileContents(entry, fileContent, send, onCompilationFinished);
-  }, 20);
+  }, 0);
 
   if (entry.compilation != null) {
     entry.compilation.timeout = timeout;
@@ -727,6 +728,7 @@ async function compileContents(
   }
 }
 
+// TODO(compilation-revamp) make sure we don't unecessarily trigger incremental compilations
 export function handleUpdateOpenedFile(
   filePath: string,
   fileContent: string,

server/src/server.ts

@@ -673,13 +673,22 @@ function semanticTokens(msg: p.RequestMessage) {
   return response;
 }
 
-function completion(msg: p.RequestMessage) {
+async function completion(msg: p.RequestMessage) {
   // https://microsoft.github.io/language-server-protocol/specifications/specification-current/#textDocument_completion
   let params = msg.params as p.ReferenceParams;
   let filePath = fileURLToPath(params.textDocument.uri);
   let code = getOpenedFileContent(params.textDocument.uri);
   let tmpname = utils.createFileInTempDir();
   fs.writeFileSync(tmpname, code, { encoding: "utf-8" });
+
+  if (config.extensionConfiguration.newCompletion) {
+    await new Promise<void>((resolve) => {
+      ic.triggerIncrementalCompilationOfFile(filePath, code, send, () => {
+        resolve();
+      });
+    });
+  }
+
   let response = utils.runAnalysisCommand(
     filePath,
     [
@@ -1235,7 +1244,7 @@ function onMessage(msg: p.Message) {
     } else if (msg.method === p.DocumentSymbolRequest.method) {
       send(documentSymbol(msg));
     } else if (msg.method === p.CompletionRequest.method) {
-      send(completion(msg));
+      completion(msg).then(send);
     } else if (msg.method === p.CompletionResolveRequest.method) {
       send(completionResolve(msg));
     } else if (msg.method === p.SemanticTokensRequest.method) {

server/src/utils.ts

@@ -229,6 +229,10 @@ export let runAnalysisAfterSanityCheck = (
         config.extensionConfiguration.cache?.projectConfig?.enable === true
           ? "true"
           : undefined,
+      RESCRIPT_NEW_ANALYSIS_ENGINE:
+        config.extensionConfiguration.newCompletion === true
+          ? "true"
+          : undefined,
     },
   };