fix: Avoid accidentally treating '' as valid

extensions/ql-vscode/src/archive-filesystem-provider.ts

@@ -169,7 +169,7 @@ export class ArchiveFileSystemProvider implements vscode.FileSystemProvider {
   async readDirectory(uri: vscode.Uri): Promise<[string, vscode.FileType][]> {
     const ref = decodeSourceArchiveUri(uri);
     const archive = await this.getArchive(ref.sourceArchiveZipPath);
-    let contents = archive.dirMap.get(ref.pathWithinSourceArchive);
+    const contents = archive.dirMap.get(ref.pathWithinSourceArchive);
     const result = contents === undefined ? [] : Array.from(contents.entries());
     if (result === undefined) {
       throw vscode.FileSystemError.FileNotFound(uri);

extensions/ql-vscode/src/config.ts

@@ -111,7 +111,7 @@ abstract class ConfigListener extends DisposableObject {
 
 export class DistributionConfigListener extends ConfigListener implements DistributionConfig {
   public get customCodeQlPath(): string | undefined {
-    return CUSTOM_CODEQL_PATH_SETTING.getValue() ? CUSTOM_CODEQL_PATH_SETTING.getValue() : undefined;
+    return CUSTOM_CODEQL_PATH_SETTING.getValue() || undefined;
   }
 
   public get includePrerelease(): boolean {
@@ -119,7 +119,7 @@ export class DistributionConfigListener extends ConfigListener implements Distri
   }
 
   public get personalAccessToken(): string | undefined {
-    return PERSONAL_ACCESS_TOKEN_SETTING.getValue() ? PERSONAL_ACCESS_TOKEN_SETTING.getValue() : undefined;
+    return PERSONAL_ACCESS_TOKEN_SETTING.getValue() || undefined;
   }
 
   public get onDidChangeDistributionConfiguration(): Event<void> {

extensions/ql-vscode/src/distribution.ts

@@ -99,7 +99,7 @@ export class DistributionManager implements DistributionProvider {
    */
   public async getCodeQlPathWithoutVersionCheck(): Promise<string | undefined> {
     // Check config setting, then extension specific distribution, then PATH.
-    if (this._config.customCodeQlPath !== undefined) {
+    if (this._config.customCodeQlPath) {
       if (!await fs.pathExists(this._config.customCodeQlPath)) {
         showAndLogErrorMessage(`The CodeQL executable path is specified as "${this._config.customCodeQlPath}" ` +
           "by a configuration setting, but a CodeQL executable could not be found at that path. Please check " +
@@ -520,8 +520,11 @@ export enum FindDistributionResultKind {
   NoDistribution
 }
 
-export type FindDistributionResult = CompatibleDistributionResult | UnknownCompatibilityDistributionResult |
-  IncompatibleDistributionResult | NoDistributionResult;
+export type FindDistributionResult =
+  | CompatibleDistributionResult
+  | UnknownCompatibilityDistributionResult
+  | IncompatibleDistributionResult
+  | NoDistributionResult;
 
 interface CompatibleDistributionResult {
   codeQlPath: string;
@@ -551,8 +554,11 @@ export enum DistributionUpdateCheckResultKind {
   UpdateAvailable
 }
 
-type DistributionUpdateCheckResult = AlreadyCheckedRecentlyResult | AlreadyUpToDateResult | InvalidLocationResult |
-  UpdateAvailableResult;
+type DistributionUpdateCheckResult =
+  | AlreadyCheckedRecentlyResult
+  | AlreadyUpToDateResult
+  | InvalidLocationResult
+  | UpdateAvailableResult;
 
 export interface AlreadyCheckedRecentlyResult {
   kind: DistributionUpdateCheckResultKind.AlreadyCheckedRecentlyResult;