src/vs/workbench/api/common/extHostExtensionService.ts/AbstractExtHostExtensionService/_createExtensionPathIndex
class AbstractExtHostExtensionService:	private async _createExtensionPathIndex(extensions: IExtensionDescription[]): Promise<TernarySearchTree<URI, IExtensionDescription>> {
		const tst = TernarySearchTree.forUris<IExtensionDescription>(key => {
			// using the default/biased extUri-util because the IExtHostFileSystemInfo-service
			// isn't ready to be used yet, e.g the knowledge about `file` protocol and others
			// comes in while this code runs
			return extUriBiasedIgnorePathCase.ignorePathCasing(key);
		});
		// const tst = TernarySearchTree.forUris<IExtensionDescription>(key => true);
		await Promise.all(extensions.map(async (ext) => {
			if (this._getEntryPoint(ext)) {
				const uri = await this._realPathExtensionUri(ext.extensionLocation);
				tst.set(uri, ext);
			}
		}));
		return tst;
	}