---
id: post/jpearson-blog/1590
type: post
title: Why do all my tests show up twice in the test explorer?
summary: "Tests show up twice in the VS Code test explorer when the pre-release AL Language extension, which now finds tests itself, is installed alongside AL Test Runner. The author suggests going back to the release AL Language version for now. He suspects a bug: test runs hang against containers older than BC28, which leaves Copilot waiting for results."
tier: community
language: en
tags:
  - testing
  - al language
  - test explorer
  - extension conflict
  - debugging
  - copilot
system: development
review:
  state: reviewed
  by: opus
  at: "2026-10-08T01:57:02.099Z"
  flags: []
generated:
  at: "2026-10-08T01:26:53.141Z"
  pipeline: 0.2.0
  prompts:
    extract-post: 1
  input_hash: aa23369ee7e985624d9708c8823a4542d4c14a8e8fc0cc5c7100e9bcf79b412f
evidence:
  - kind: blog
    url: https://jpearson.blog/2026/02/05/why-do-all-my-tests-show-up-twice-in-the-test-explorer/
    title: Why do all my tests show up twice in the test explorer?
    date: "2026-02-05"
    commit: null
    t: null
    quote: null
links:
  learn: []
  objects: []
  features: []
  topics: []
  localizations: []
  videos: []
  posts: []
  guidelines: []
post_id: "1590"
source_id: jpearson-blog
source_name: James Pearson
url: https://jpearson.blog/2026/02/05/why-do-all-my-tests-show-up-twice-in-the-test-explorer/
published_at: "2026-02-05T11:07:28.000Z"
author: James Pearson
full_text: false
words: 403
quotes: []
code_objects_mentioned: []
systems:
  - development
  - platform
versions_mentioned:
  - BC28
preview:
  embeddable: true
  frame_url: https://jpearson.blog/2026/02/05/why-do-all-my-tests-show-up-twice-in-the-test-explorer/embed/
  image: https://jpearson.blog/wp-content/uploads/2026/02/image.png
  image_alt: null
  image_w: 349
  image_h: 414
  site_name: James Pearson
  favicon: https://jpearson.blog/wp-content/uploads/2018/09/cropped-semicolon.jpg?w=32
  probed_at: "2026-10-07T11:50:41.353Z"
---

# Why do all my tests show up twice in the test explorer?

[Read the post](https://jpearson.blog/2026/02/05/why-do-all-my-tests-show-up-twice-in-the-test-explorer/) · James Pearson (James Pearson) · 2026-02-05 · 403 words · tier community · reviewed (checked by Opus)

> Tests show up twice in the VS Code test explorer when the pre-release AL Language extension, which now finds tests itself, is installed alongside AL Test Runner. The author suggests going back to the release AL Language version for now. He suspects a bug: test runs hang against containers older than BC28, which leaves Copilot waiting for results.

## Key points

- The pre-release AL Language extension adds its own AL Tests tree to the test explorer, which duplicates the AL Test Runner entries
- With BC28 the AL Language extension can connect to the server to run tests; earlier versions lack this execution support
- An All Tests run against a pre-BC28 container never finishes, so an AI model running tests waits forever; the author filed a GitHub issue
- AL Test Runner still offers extra features such as code coverage, downloading performance profiles and running page scripts
- The author will keep maintaining AL Test Runner until Microsoft's tooling is rich enough to replace it

## Context

- Features: test discovery, test execution, test explorer, code coverage, performance profiling, page scripts, copilot integration
- Versions: BC28

Source: James Pearson, community blog. Summary, key points and quotes are derived (CONTENT-NOTICE.md); read the original for the full text.