block interpreters from Positron dropdown (#6525)

Should block <3.8 interpreters from being registered when found. It
seems to fix everything for me locally, I think this is the only place
where old interpreters could sneak by.

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#### New Features

- N/A

#### Bug Fixes

- #3740 


### QA Notes

1. Create a Python interpreter <3.8 (if you are a pyenv user, you can do
pyenv install 3.6)
2. Fo to `Python: Select Interpreter`, should not appear in dropdown
3. Go to Positron interpreter selector, should not appear here either

extensions/positron-python/src/client/positron/manager.ts

@@ -21,11 +21,13 @@ import { traceError, traceInfo } from '../logging';
 import { IConfigurationService, IDisposable } from '../common/types';
 import { PythonRuntimeSession } from './session';
 import { createPythonRuntimeMetadata, PythonRuntimeExtraData } from './runtime';
-import { EXTENSION_ROOT_DIR } from '../common/constants';
+import { EXTENSION_ROOT_DIR, MINIMUM_PYTHON_VERSION } from '../common/constants';
 import { JupyterKernelSpec } from '../positron-supervisor.d';
 import { IEnvironmentVariablesProvider } from '../common/variables/types';
 import { checkAndInstallPython } from './extension';
-import { shouldIncludeInterpreter } from './interpreterSettings';
+import { shouldIncludeInterpreter, isVersionSupported } from './interpreterSettings';
+import { parseVersion, toSemverLikeVersion } from '../pythonEnvironments/base/info/pythonVersion';
+import { PythonVersion } from '../pythonEnvironments/info/pythonVersion';
 
 export const IPythonRuntimeManager = Symbol('IPythonRuntimeManager');
 
@@ -116,7 +118,14 @@ export class PythonRuntimeManager implements IPythonRuntimeManager {
      */
     public registerLanguageRuntime(runtime: positron.LanguageRuntimeMetadata): void {
         const extraData = runtime.extraRuntimeData as PythonRuntimeExtraData;
+        const pythonVersion: PythonVersion = toSemverLikeVersion(parseVersion(runtime.languageVersion));
+
         // Check if the interpreter should be included in the list of registered runtimes
+        if (!isVersionSupported(pythonVersion, MINIMUM_PYTHON_VERSION)) {
+            traceInfo(`Not registering runtime ${extraData.pythonPath} as it is not a supported version.`);
+            return;
+        }
+
         if (shouldIncludeInterpreter(extraData.pythonPath)) {
             // Save the runtime for later use
             this.registeredPythonRuntimes.set(extraData.pythonPath, runtime);

extensions/positron-python/src/client/pythonEnvironments/base/info/pythonVersion.ts

@@ -233,7 +233,10 @@ function compareVersionRelease(left: PythonVersion, right: PythonVersion): [numb
  * Convert Python version to semver like version object.
  *
  * Remarks: primarily used to convert to old type of environment info.
- * @deprecated
+ * // --- Start Positron ---
+ *  This is used in environment discovery.
+ *  Upstream has deprecated, but do not remove.
+ * // --- End Positron ---
  */
 export function toSemverLikeVersion(
     version: PythonVersion,

extensions/positron-python/src/test/positron/manager.unit.test.ts

@@ -15,6 +15,7 @@ import * as fs from '../../client/common/platform/fs-paths';
 import * as runtime from '../../client/positron/runtime';
 import * as session from '../../client/positron/session';
 import * as workspaceApis from '../../client/common/vscodeApis/workspaceApis';
+import * as interpreterSettings from '../../client/positron/interpreterSettings';
 import { IEnvironmentVariablesProvider } from '../../client/common/variables/types';
 import { IConfigurationService, IDisposable } from '../../client/common/types';
 import { IServiceContainer } from '../../client/ioc/types';
@@ -36,6 +37,7 @@ suite('Python runtime manager', () => {
     let workspaceConfig: TypeMoq.IMock<WorkspaceConfiguration>;
 
     let getConfigurationStub: sinon.SinonStub;
+    let isVersionSupportedStub: sinon.SinonStub;
 
     let pythonRuntimeManager: PythonRuntimeManager;
     let disposables: IDisposable[];
@@ -68,6 +70,9 @@ suite('Python runtime manager', () => {
             return undefined;
         });
 
+        isVersionSupportedStub = sinon.stub(interpreterSettings, 'isVersionSupported');
+        isVersionSupportedStub.returns(true);
+
         pythonRuntimeManager = new PythonRuntimeManager(serviceContainer.object, interpreterService.object);
         disposables = [];
     });