Don't suggest adding an alias to an extern alias that is not a valid identitifer

Description

Contributor guide

Tech stack

csharp

Domain

developer experiencebackend

Issue type

bug

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

3

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

1-3 hours

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

stale

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

clear

Prerequisites

C# knowledgeRoslyn compiler basicsUnderstanding of identifier validation

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

60

Research direction

The issue is about preventing the suggestion of an alias that is not a valid identifier. Look at the completion provider in Roslyn that handles extern alias suggestions. Specifically, examine the class `ExternAliasCompletionProvider` or similar. The fix involves adding a check that the alias string is a valid C# identifier before suggesting it. Review existing tests for alias completion to understand the expected behavior. The change should be small and localized to the suggestion logic.