Correct MacOS check and lay infra for Linux checks

src/client/activation/languageServer.ts

@@ -127,9 +127,13 @@ export class LanguageServerExtensionActivator implements IExtensionActivator {
 
     private checkSupportedPlatform(): boolean {
         const platform = this.services.get<IPlatformService>(IPlatformService);
-        if (platform.isMac && platform.versionMajor === 10 && platform.versionMinor < 12) {
-            this.services.get<ILogger>(ILogger).logError('Unsupported MacOS');
-            this.appShell.showErrorMessage('Microsoft Python Language Server does not support MacOS older than 10.12.');
+        if (!platform.isNetCoreCompatibleOS) {
+            if (platform.isMac) {
+                this.services.get<ILogger>(ILogger).logError('Unsupported MacOS');
+                this.appShell.showErrorMessage('Microsoft Python Language Server does not support MacOS older than 10.12.');
+            }
+            // tslint:disable-next-line:no-suspicious-comment
+            // TODO: Linux messages
             return false;
         }
         return true;

src/client/common/platform/platformService.ts

@@ -5,7 +5,29 @@
 import { injectable } from 'inversify';
 import { arch, release } from 'os';
 import { NON_WINDOWS_PATH_VARIABLE_NAME, WINDOWS_PATH_VARIABLE_NAME } from './constants';
-import { IPlatformService } from './types';
+import { IPlatformService, IVersion } from './types';
+
+class OSVersion implements IVersion {
+    public get versionString(): string {
+        return release();
+    }
+    public get versionMajor(): number {
+        const parts = this.versionString.split('.');
+        return parts.length > 0 ? parseInt(parts[0], 10) : 0;
+    }
+    public get versionMinor(): number {
+        const parts = this.versionString.split('.');
+        return parts.length > 1 ? parseInt(parts[1], 10) : 0;
+    }
+}
+
+class MacOSVersion {
+    public get isCompatibleOS(): boolean {
+        // https://en.wikipedia.org/wiki/Darwin_%28operating_system%29#Release_history
+        // 10.12 == Darwin 16.0
+        return new OSVersion().versionMajor >= 16;
+    }
+}
 
 @injectable()
 export class PlatformService implements IPlatformService {
@@ -34,15 +56,18 @@ export class PlatformService implements IPlatformService {
     public get virtualEnvBinName() {
         return this.isWindows ? 'scripts' : 'bin';
     }
-    public get version(): string {
-        return release();
-    }
-    public get versionMajor(): number {
-        const parts = this.version.split('.');
-        return parts.length > 0 ? parseInt(parts[0], 10) : 0;
-    }
-    public get versionMinor(): number {
-        const parts = this.version.split('.');
-        return parts.length > 1 ? parseInt(parts[1], 10) : 0;
+    public get isNetCoreCompatibleOS(): boolean {
+        if (this.isMac) {
+            return new MacOSVersion().isCompatibleOS;
+        }
+        // tslint:disable-next-line:no-suspicious-comment
+        // TODO: implement Linux checks. They are all over.
+        // release() reports kernel version. For the actual
+        // OS version run 'lsb_release -a' on Ubuntu,
+        // 'cat /etc/centos-release' on CentOS
+        // 'cat /etc/fedora-release' on Fedora
+        // 'cat /etc/lsb-release' on Mint
+        // 'cat /etc/redhat-release' on Red Hat
+        return true; // Windows matches between .NET Core and VS Code.
     }
 }

src/client/common/platform/types.ts

@@ -27,9 +27,7 @@ export interface IPlatformService {
     is64bit: boolean;
     pathVariableName: 'Path' | 'PATH';
     virtualEnvBinName: 'bin' | 'scripts';
-    version: string;
-    versionMajor: number;
-    versionMinor: number;
+    isNetCoreCompatibleOS: boolean;
 }
 
 export type TemporaryFile = { filePath: string } & Disposable;
@@ -56,3 +54,9 @@ export interface IFileSystem {
     search(globPattern: string): Promise<string[]>;
     createTemporaryFile(extension: string): Promise<TemporaryFile>;
 }
+
+export interface IVersion {
+    readonly versionString: string;
+    readonly versionMajor: number;
+    readonly versionMinor: number;
+}