Provide way to specify R path directly

src/LanguageServer/Impl/LanguageServer.cs

@@ -197,7 +197,8 @@ public Task didChangeConfiguration(JToken token, CancellationToken ct) {
                 return Task.CompletedTask;
             }
 
-            settings.Interpreter = GetSetting(r, "interpreter", 0);
+            settings.InterpreterIndex = GetSetting(r, "interpreter", 0);
+            settings.InterpreterPath = GetSetting(r, "interpreterPath", string.Empty);
 
             var editor = r["editor"];
             settings.Editor.TabSize = GetSetting(editor, "tabSize", 2);

src/LanguageServer/Impl/Server/LanguageServerSettings.cs

@@ -15,7 +15,14 @@ namespace Microsoft.R.LanguageServer.Server {
     /// 
     /// </remarks>
     public sealed class LanguageServerSettings {
-        public int Interpreter { get; set; }
+        /// <summary>
+        /// Interpreter index in discovered interpreters.
+        /// </summary>
+        public int InterpreterIndex { get; set; }
+        /// <summary>
+        /// Path to R installation. Overrides <see cref="InterpreterIndex"/>.
+        /// </summary>
+        public string InterpreterPath { get; set; }
         public EditorSettings Editor { get; set; } = new EditorSettings();
         public LinterSettings Linting { get; set; } = new LinterSettings();
     }

src/LanguageServer/Impl/Server/RConnection.cs

@@ -3,10 +3,12 @@
 
 using System;
 using System.Diagnostics;
+using System.IO;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Common.Core;
+using Microsoft.Common.Core.IO;
 using Microsoft.Common.Core.Logging;
 using Microsoft.Common.Core.Services;
 using Microsoft.R.Components.InteractiveWorkflow;
@@ -16,6 +18,7 @@
 using Microsoft.R.LanguageServer.InteractiveWorkflow;
 using Microsoft.R.LanguageServer.Settings;
 using Microsoft.R.Platform.Interpreters;
+using Microsoft.R.Platform.Windows.Interpreters;
 
 namespace Microsoft.R.LanguageServer.Server {
     /// <summary>
@@ -86,6 +89,12 @@ private async Task ConnectAsync(CancellationToken ct) {
         public void Dispose() => _workflow?.Dispose();
 
         private IRInterpreterInfo GetREngine() {
+            var rs = _services.GetService<IREngineSettings>();
+            if (!string.IsNullOrEmpty(rs.InterpreterPath)) {
+                _ui.LogMessageAsync($"Using interpreter at '{rs.InterpreterPath}']", MessageType.Info).DoNotWait();
+                return new RInterpreterInfo("R", rs.InterpreterPath, _services.GetService<IFileSystem>());
+            }
+
             var ris = _services.GetService<IRInstallationService>();
             var engines = ris
                 .GetCompatibleEngines(new SupportedRVersionRange(3, 2, 4, 9))
@@ -103,8 +112,8 @@ private IRInterpreterInfo GetREngine() {
                 _ui.LogMessageAsync($"\t[{i}] {engines[i].Name}", MessageType.Info).DoNotWait();
             }
             _ui.LogMessageAsync("You can specify the desired interpreter index in the R settings", MessageType.Info).DoNotWait();
+            _ui.LogMessageAsync("Of provide path to R using `r.interpreterPath` setting.", MessageType.Info).DoNotWait();
 
-            var rs = _services.GetService<IREngineSettings>();
             if (rs.InterpreterIndex < 0 || rs.InterpreterIndex > engines.Count) {
                 _ui.ShowMessageAsync($"Selected interpreter [{rs.InterpreterIndex}] does not exist. Using [0] instead", MessageType.Warning).DoNotWait();
                 rs.InterpreterIndex = 0;

src/LanguageServer/Impl/Server/SettingsManager.cs

@@ -47,7 +47,8 @@ public void UpdateSettings(LanguageServerSettings vscodeSettings) {
             _editorSettings.LintOptions = vscodeSettings.Linting;
             _editorSettings.RaiseChanged();
 
-            _engineSettings.InterpreterIndex = vscodeSettings.Interpreter;
+            _engineSettings.InterpreterIndex = vscodeSettings.InterpreterIndex;
+            _engineSettings.InterpreterPath = vscodeSettings.InterpreterPath;
 
             SettingsChanged?.Invoke(this, EventArgs.Empty);
         }
@@ -57,6 +58,7 @@ public void UpdateSettings(LanguageServerSettings vscodeSettings) {
 #pragma warning disable 67
         private sealed class REngineSettings : IREngineSettings {
             public int InterpreterIndex { get; set; }
+            public string InterpreterPath { get; set; }
         }
 
         private sealed class REditorSettings : IREditorSettings {

src/LanguageServer/Impl/Settings/IREngineSettings.cs

@@ -4,5 +4,6 @@
 namespace Microsoft.R.LanguageServer.Settings {
     public interface IREngineSettings {
         int InterpreterIndex { get; set; }
+        string InterpreterPath { get; set; }
     }
 }

src/R/Platform/Impl/Windows/Interpreters/RInterpreterInfo.cs

@@ -51,7 +51,7 @@ public RInterpreterInfo(string name, string path, IFileSystem fileSystem) {
             _fileSystem = fileSystem;
             Name = name;
             InstallPath = NormalizeRPath(path);
-            BinPath = Path.Combine(path, @"bin\x64");
+            BinPath = Path.Combine(path, "bin", "x64");
             Version = DetermineVersion();
             DocPath = Path.Combine(path, "doc");
             IncludePath = Path.Combine(path, "include");

src/VSCode/.eslintignore

@@ -0,0 +1,6 @@
+**/dist/**
+**/out/**
+**/node_modules/**
+**/client/server/**
+**/extension/server/**
+**/tests/fourslash/**

src/VSCode/.eslintrc.json

@@ -0,0 +1,37 @@
+{
+    "extends": [
+        "eslint:recommended",
+        "prettier",
+        "plugin:@typescript-eslint/recommended"
+    ],
+    "env": {
+        "browser": true
+    },
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "ecmaVersion": 2017,
+        "sourceType": "module"
+    },
+    "plugins": [
+        "@typescript-eslint/eslint-plugin",
+        "simple-import-sort"
+    ],
+    "rules": {
+        "eqeqeq": "error",
+        "no-constant-condition": 0,
+        "no-inner-declarations": 0,
+        "no-undef": 0,
+        "simple-import-sort/sort": "error",
+        "@typescript-eslint/explicit-function-return-type": 0,
+        "@typescript-eslint/explicit-module-boundary-types": 0,
+        "@typescript-eslint/ban-types": 0,
+        "@typescript-eslint/camelcase": 0,
+        "@typescript-eslint/no-empty-interface": 0,
+        "@typescript-eslint/no-explicit-any": 0,
+        "@typescript-eslint/no-namespace": 0,
+        "@typescript-eslint/no-non-null-assertion": 0,
+        "@typescript-eslint/no-this-alias": 0,
+        "@typescript-eslint/no-unused-vars": 0,
+        "@typescript-eslint/no-use-before-define": 0
+    }
+}

src/VSCode/.prettierignore

@@ -0,0 +1,8 @@
+*.json
+**/pyright/**/*.md
+**/dist/**
+**/out/**
+**/client/server/**
+**/extension/server/**
+**/typeshed-fallback/**
+**/bundled-stubs/**

src/VSCode/.prettierrc

@@ -0,0 +1,15 @@
+{
+    "singleQuote": true,
+    "tabWidth": 4,
+    "useTabs": false,
+    "printWidth": 120,
+    "endOfLine": "auto",
+    "overrides": [
+        {
+            "files": ["*.yml", "*.yaml"],
+            "options": {
+                "tabWidth": 2
+            }
+        }
+    ]
+}

src/VSCode/CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## 0.0.9 (28 June 2020)
+
+### Updates 
+
+1. Provide `r.interpreterPath` manual setting for cases when R does not get discovered automatically.
+
 ## 0.0.8 (01 May 2020)
 
 ### Updates 

src/VSCode/README.md

@@ -44,9 +44,18 @@ Use `R: Execute line or selection` commands to execute line or selection in the
 R session in the editor does not automatically pick up new packages installed in the terminal. You may have to reload the window for the session to pick up newly installed modules.
 
 ## Troubleshooting
-- **.NET Core not found** You can bypass .NET Core check by setting `dependencyChecks` setting to false.
-- **Launching server using command dotnet failed.**. Most probably libzip is missing and extensions was unable to install it. Try installing [Homebrew](https://brew.sh/), then run `brew install libzip`.
-- **R Interpreter not found** 
+**.NET Core not found** 
+
+You can bypass .NET Core check by setting `dependencyChecks` setting to false.
+
+**Launching server using command dotnet failed.**. 
+
+Most probably libzip is missing and extensions was unable to install it. Try installing [Homebrew](https://brew.sh/), then run `brew install libzip`.
+
+**R Interpreter not found**
+
+Try using `r.intepreterPath` setting and specify path to R installation. The path should be root folder, like `C:\Program Files\R\R-3.4.3`, without `bin/x64`.
+
 The broker (ASP.NET Core process) is configurable via `Microsoft.R.Host.Broker.Config.json`. Example:
 ```
 "r":{"autoDetect":"<true|false>"}