Language server; error location in SyntaxErrors

packages/squiggle-lang/bsconfig.json

@@ -31,6 +31,7 @@
       "basic": false
     }
   },
+  "external-stdlib": "@rescript/std",
   "refmt": 3,
   "warnings": {
     "number": "+A-42-48-9-30-4"

packages/squiggle-lang/package.json

@@ -36,12 +36,12 @@
   ],
   "author": "Quantified Uncertainty Research Institute",
   "dependencies": {
+    "@rescript/std": "^9.1.4",
     "@stdlib/stats": "^0.0.13",
     "jstat": "^1.9.5",
     "lodash": "^4.17.21",
     "mathjs": "^10.6.0",
-    "pdfast": "^0.2.0",
-    "rescript": "^9.1.4"
+    "pdfast": "^0.2.0"
   },
   "devDependencies": {
     "@glennsl/rescript-jest": "^0.9.0",
@@ -58,6 +58,7 @@
     "nyc": "^15.1.0",
     "peggy": "^2.0.1",
     "reanalyze": "^2.23.0",
+    "rescript": "^9.1.4",
     "rescript-fast-check": "^1.1.1",
     "ts-jest": "^27.1.4",
     "ts-loader": "^9.3.0",

packages/squiggle-lang/src/js/index.ts

@@ -10,6 +10,7 @@ import {
   evaluatePartialUsingExternalBindings,
   evaluateUsingOptions,
   foreignFunctionInterface,
+  parse as parseRescript,
 } from "../rescript/TypescriptInterface.gen";
 export {
   makeSampleSetDist,
@@ -31,7 +32,7 @@ import {
   convertRawToTypescript,
   lambdaValue,
 } from "./rescript_interop";
-import { result, resultMap, tag, tagged } from "./types";
+import { Ok, result, resultMap, tag, tagged } from "./types";
 import { Distribution, shape } from "./distribution";
 
 export { Distribution, resultMap, defaultEnvironment };
@@ -58,6 +59,23 @@ export function run(
   return resultMap(res, (x) => createTsExport(x, e));
 }
 
+export function parse(
+  squiggleString: string
+): result<null, Extract<errorValue, { tag: "RESyntaxError" }>> {
+  const maybeExpression = parseRescript(squiggleString);
+  if (maybeExpression.tag === "Ok") {
+    return Ok(null); // TODO - return AST
+  } else {
+    if (
+      typeof maybeExpression.value !== "object" ||
+      maybeExpression.value.tag !== "RESyntaxError"
+    ) {
+      throw new Error("Expected syntax error");
+    }
+    return { tag: "Error", value: maybeExpression.value };
+  }
+}
+
 // Run Partial. A partial is a block of code that doesn't return a value
 export function runPartial(
   squiggleString: string,

packages/squiggle-lang/src/rescript/Reducer/Reducer_ErrorValue.res

@@ -1,3 +1,6 @@
+@gentype.import("peggy") @genType.as("LocationRange")
+type location
+
 @genType
 type errorValue =
   | REArityError(option<string>, int, int) //TODO: Binding a lambda to a variable should record the variable name in lambda for error reporting
@@ -14,7 +17,7 @@ type errorValue =
   | REOperationError(Operation.operationError)
   | RERecordPropertyNotFound(string, string)
   | RESymbolNotFound(string)
-  | RESyntaxError(string)
+  | RESyntaxError(string, option<location>)
   | RETodo(string) // To do
   | REUnitNotFound(string)
 
@@ -50,7 +53,7 @@ let errorToString = err =>
   | RENotAFunction(valueString) => `${valueString} is not a function`
   | RERecordPropertyNotFound(msg, index) => `${msg}: ${index}`
   | RESymbolNotFound(symbolName) => `${symbolName} is not defined`
-  | RESyntaxError(desc) => `Syntax Error: ${desc}`
+  | RESyntaxError(desc, _) => `Syntax Error: ${desc}`
   | RETodo(msg) => `TODO: ${msg}`
   | REExpectedType(typeName) => `Expected type: ${typeName}`
   | REUnitNotFound(unitName) => `Unit not found: ${unitName}`

packages/squiggle-lang/src/rescript/Reducer/Reducer_Expression/Reducer_Expression.res

@@ -157,7 +157,7 @@ let evaluatePartialUsingExternalBindings = (
   switch rAnswer {
   | Ok(EvRecord(externalBindings)) => Ok(externalBindings)
   | Ok(_) =>
-    Error(Reducer_ErrorValue.RESyntaxError(`Partials must end with an assignment or record`))
+    Error(Reducer_ErrorValue.RESyntaxError(`Partials must end with an assignment or record`, None))
   | Error(err) => err->Error
   }
 }

packages/squiggle-lang/src/rescript/Reducer/Reducer_Peggy/Reducer_Peggy_Parse.res

@@ -5,11 +5,15 @@ type node = {"type": string}
 
 @module("./Reducer_Peggy_GeneratedParser.js") external parse__: string => node = "parse"
 
+let syntaxErrorToLocation: Js.Exn.t => Reducer_ErrorValue.location = error => %raw(`error.location`)
+
+@genType
 let parse = (expr: string): result<node, errorValue> =>
   try {
     Ok(parse__(expr))
   } catch {
-  | Js.Exn.Error(obj) => REJavaScriptExn(Js.Exn.message(obj), Js.Exn.name(obj))->Error
+  | Js.Exn.Error(obj) =>
+    RESyntaxError(Belt.Option.getExn(Js.Exn.message(obj)), syntaxErrorToLocation(obj)->Some)->Error
   }
 
 type nodeBlock = {...node, "statements": array<node>}

packages/squiggle-lang/src/rescript/TypescriptInterface.res

@@ -40,6 +40,9 @@ let evaluate = Reducer.evaluate
 @genType
 let evaluateUsingOptions = Reducer.evaluateUsingOptions
 
+@genType
+let parse = Reducer_Peggy_Parse.parse
+
 @genType
 let evaluatePartialUsingExternalBindings = Reducer.evaluatePartialUsingExternalBindings
 

packages/vscode-ext/.gitignore

@@ -1,4 +1,5 @@
 /media/vendor
-/out
+/client/out
+/server/out
 /*.vsix
 /syntaxes/*.json

packages/vscode-ext/client/src/client.ts

@@ -0,0 +1,60 @@
+import * as path from "path";
+
+import * as vscode from "vscode";
+import {
+  LanguageClient,
+  LanguageClientOptions,
+  ServerOptions,
+  TransportKind,
+} from "vscode-languageclient/node";
+
+let client: LanguageClient;
+
+export const startClient = (context: vscode.ExtensionContext) => {
+  // The server is implemented in node
+  let serverModule = context.asAbsolutePath(
+    path.join("server", "out", "server.js")
+  );
+  // The debug options for the server
+  // --inspect=6009: runs the server in Node's Inspector mode so VS Code can attach to the server for debugging
+  let debugOptions = { execArgv: ["--nolazy", "--inspect=6009"] };
+
+  // If the extension is launched in debug mode then the debug server options are used
+  // Otherwise the run options are used
+  let serverOptions: ServerOptions = {
+    run: { module: serverModule, transport: TransportKind.ipc },
+    debug: {
+      module: serverModule,
+      transport: TransportKind.ipc,
+      options: debugOptions,
+    },
+  };
+
+  // Options to control the language client
+  let clientOptions: LanguageClientOptions = {
+    // Register the server for plain text documents
+    documentSelector: [{ scheme: "file", language: "squiggle" }],
+    synchronize: {
+      // Notify the server about file changes to '.clientrc files contained in the workspace
+      fileEvents: vscode.workspace.createFileSystemWatcher("**/.clientrc"),
+    },
+  };
+
+  // Create the language client and start the client.
+  client = new LanguageClient(
+    "squiggleServer",
+    "Squiggle Server",
+    serverOptions,
+    clientOptions
+  );
+
+  // Start the client. This will also launch the server
+  client.start();
+};
+
+export const stopClient = () => {
+  if (!client) {
+    return undefined;
+  }
+  return client.stop();
+};

packages/vscode-ext/src/extension.ts → packages/vscode-ext/client/src/extension.ts

@@ -1,6 +1,7 @@
 // The module 'vscode' contains the VS Code extensibility API
 // Import the module and reference it with the alias vscode in your code below
 import * as vscode from "vscode";
+import { startClient, stopClient } from "./client";
 
 import { SquiggleEditorProvider } from "./editor";
 import { registerPreviewCommand } from "./preview";
@@ -11,7 +12,11 @@ export function activate(context: vscode.ExtensionContext) {
   context.subscriptions.push(SquiggleEditorProvider.register(context));
 
   registerPreviewCommand(context);
+
+  startClient(context);
 }
 
 // this method is called when your extension is deactivated
-export function deactivate() {}
+export function deactivate() {
+  stopClient();
+}

packages/vscode-ext/client/tsconfig.json

@@ -0,0 +1,12 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "target": "es2020",
+    "lib": ["ES2020", "dom"],
+    "outDir": "out",
+    "rootDir": "src",
+    "sourceMap": true
+  },
+  "include": ["src"],
+  "exclude": ["node_modules", ".vscode-test"]
+}

packages/vscode-ext/package.json

@@ -3,7 +3,7 @@
   "displayName": "Squiggle",
   "description": "Squiggle language support",
   "license": "MIT",
-  "version": "0.1.2",
+  "version": "0.2.0",
   "publisher": "QURI",
   "repository": {
     "type": "git",
@@ -18,10 +18,11 @@
     "Visualization"
   ],
   "activationEvents": [
+    "onLanguage:squiggle",
     "onCustomEditor:squiggle.wysiwyg",
     "onCommand:squiggle.preview"
   ],
-  "main": "./out/extension.js",
+  "main": "./client/out/extension.js",
   "contributes": {
     "languages": [
       {
@@ -130,8 +131,9 @@
     "compile": "yarn run compile:tsc && yarn run compile:grammar && yarn run compile:vendor",
     "watch": "tsc -watch -p ./",
     "pretest": "yarn run compile && yarn run lint",
-    "lint": "eslint src --ext ts",
-    "format": "eslint src --ext ts --fix"
+    "lint": "eslint client/src server/src --ext ts",
+    "format": "eslint client/src server/src --ext ts --fix",
+    "package": "npx vsce package --yarn"
   },
   "devDependencies": {
     "@types/glob": "^7.2.0",
@@ -142,6 +144,13 @@
     "eslint": "^8.18.0",
     "glob": "^8.0.3",
     "js-yaml": "^4.1.0",
-    "typescript": "^4.7.4"
+    "typescript": "^4.7.4",
+    "vsce-yarn-patch": "^1.66.2"
+  },
+  "dependencies": {
+    "vscode-languageclient": "^8.0.1",
+    "vscode-languageserver": "^7.0.0",
+    "vscode-languageserver-textdocument": "^1.0.5",
+    "@quri/squiggle-lang": "^0.2.11"
   }
 }

packages/vscode-ext/server/src/server.ts

@@ -0,0 +1,84 @@
+import {
+  createConnection,
+  TextDocuments,
+  Diagnostic,
+  DiagnosticSeverity,
+  ProposedFeatures,
+  InitializeParams,
+  TextDocumentSyncKind,
+  InitializeResult,
+} from "vscode-languageserver/node";
+
+import { parse } from "@quri/squiggle-lang";
+
+import { TextDocument } from "vscode-languageserver-textdocument";
+
+// Create a connection for the server, using Node's IPC as a transport.
+// Also include all preview / proposed LSP features.
+let connection = createConnection(ProposedFeatures.all);
+
+const documents: TextDocuments<TextDocument> = new TextDocuments(TextDocument);
+
+documents.onDidChangeContent((change) => {
+  validateSquiggleDocument(change.document);
+});
+
+let hasDiagnosticRelatedInformationCapability = false;
+
+connection.onInitialize((params: InitializeParams) => {
+  const capabilities = params.capabilities;
+
+  hasDiagnosticRelatedInformationCapability = !!(
+    capabilities.textDocument &&
+    capabilities.textDocument.publishDiagnostics &&
+    capabilities.textDocument.publishDiagnostics.relatedInformation
+  );
+
+  const result: InitializeResult = {
+    capabilities: {
+      textDocumentSync: TextDocumentSyncKind.Incremental,
+    },
+  };
+  return result;
+});
+
+async function validateSquiggleDocument(
+  textDocument: TextDocument
+): Promise<void> {
+  // The validator creates diagnostics for all uppercase words length 2 and more
+  const text = textDocument.getText();
+  const pattern = /\b[A-Z]{2,}\b/g;
+  let m: RegExpExecArray | null;
+
+  let problems = 0;
+  const diagnostics: Diagnostic[] = [];
+
+  const parseResult = parse(text);
+  if (parseResult.tag === "Error") {
+    const location = parseResult.value.value[1];
+    diagnostics.push({
+      severity: DiagnosticSeverity.Error,
+      range: {
+        start: {
+          line: location.start.line - 1,
+          character: location.start.column - 1,
+        },
+        end: {
+          line: location.end.line - 1,
+          character: location.end.column - 1,
+        },
+      },
+      message: parseResult.value.value[0],
+    });
+  }
+
+  // Send the computed diagnostics to VSCode.
+  connection.sendDiagnostics({ uri: textDocument.uri, diagnostics });
+}
+
+// Make the text document manager listen on the connection
+// for open, change and close text document events
+documents.listen(connection);
+
+// Listen on the connection
+connection.listen();

packages/vscode-ext/server/tsconfig.json

@@ -0,0 +1,12 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "target": "es2020",
+    "lib": ["ES2020", "dom"],
+    "outDir": "out",
+    "rootDir": "src",
+    "sourceMap": true
+  },
+  "include": ["src"],
+  "exclude": ["node_modules"]
+}