Daml code relevant to reproduce the faulty behavior

Oct 13, 2025 by wbrum.org 40 views

Introduction

The Daml Language Server Protocol (LSP) is a crucial component of the Daml development experience, providing features like code completion, debugging, and more. However, some users have reported that the Daml LSP crashes in the VSCode plugin, causing inconvenience and disrupting the development workflow. In this article, we will delve into the affected Daml versions, bug description, and steps to reproduce the issue. We will also provide a clear and concise description of the expected behavior and additional context to help resolve the problem.

Affected Daml Versions

The Daml LSP crash issue has been reported in the following versions:

2.10.0: This is the latest version of Daml at the time of writing, and users have reported the crash issue in this version.
2.9.5: This is an earlier version of Daml, and users have also reported the crash issue in this version.

Bug Description

The bug description suggests that the Daml LSP is trying to send an unsupported multi-ide argument. This argument is not a valid parameter for the Daml LSP, and it seems to be causing the crash.

To Reproduce

To reproduce the faulty behavior, follow these steps:

Start the Daml service: Start the Daml service, which is required for the LSP to function.
Create a contract: Create a contract that triggers the crash issue. This may involve creating a specific choice or exercising a particular action.
Exercise the choice: Exercise the choice that triggers the crash issue.
See the error: Observe the error message that appears when the crash occurs.

Expected Behavior

The expected behavior is that the Daml LSP should function correctly, providing features like code completion, debugging, and more. The LSP should not crash or produce an error message when sending the multi-ide argument.

Additional Context

To provide a more comprehensive understanding of the issue, here are some additional context details:

OS information: The issue has been reported on various operating systems, including Windows, macOS, and Linux.
Daml code relevant to reproduce the faulty behavior: The Daml code that triggers the crash issue is not publicly available, but it is believed to involve a specific choice or action.
Logs in textual format containing relevant information: The logs do not provide any relevant information about the crash issue.
Screenshots: No screenshots are available to illustrate the issue.

Troubleshooting Steps

To troubleshoot the issue, follow these steps:

Check the Daml version: Ensure that you are running the latest version of Daml.
Verify the LSP configuration: Check the LSP configuration to ensure that it is set up correctly.
Disable extensions: Disable any extensions that may be causing the issue.
Reset the VSCode settings: Reset the VSCode settings to their default values.
Contact support: If none of the above steps resolve the issue, contact the Daml support team for further assistance.

Conclusion

Introduction

In our previous article, we explored the Daml LSP crash issue in the VSCode plugin, including the affected Daml versions, bug description, and steps to reproduce the issue. In this article, we will provide a Q&A guide to help you better understand the issue and troubleshoot it.

Q: What is the Daml LSP crash issue?

A: The Daml LSP crash issue is a problem that causes the Daml Language Server Protocol (LSP) to crash in the VSCode plugin. This can disrupt the development workflow and make it difficult to work with Daml.

Q: Which Daml versions are affected?

A: The Daml LSP crash issue has been reported in the following versions:

2.10.0: This is the latest version of Daml at the time of writing, and users have reported the crash issue in this version.
2.9.5: This is an earlier version of Daml, and users have also reported the crash issue in this version.

Q: What is the bug description?

A: The bug description suggests that the Daml LSP is trying to send an unsupported multi-ide argument. This argument is not a valid parameter for the Daml LSP, and it seems to be causing the crash.

Q: How can I reproduce the issue?

A: To reproduce the faulty behavior, follow these steps:

Start the Daml service: Start the Daml service, which is required for the LSP to function.
Create a contract: Create a contract that triggers the crash issue. This may involve creating a specific choice or exercising a particular action.
Exercise the choice: Exercise the choice that triggers the crash issue.
See the error: Observe the error message that appears when the crash occurs.

Q: What is the expected behavior?

A: The expected behavior is that the Daml LSP should function correctly, providing features like code completion, debugging, and more. The LSP should not crash or produce an error message when sending the multi-ide argument.

Q: What are the troubleshooting steps?

A: To troubleshoot the issue, follow these steps:

Check the Daml version: Ensure that you are running the latest version of Daml.
Verify the LSP configuration: Check the LSP configuration to ensure that it is set up correctly.
Disable extensions: Disable any extensions that may be causing the issue.
Reset the VSCode settings: Reset the VSCode settings to their default values.
Contact support: If none of the above steps resolve the issue, contact the Daml support team for further assistance.

Q: How can I prevent the issue from occurring?

A: To prevent the issue from occurring, ensure that you are running the latest version of Daml and that the LSP configuration is set up correctly. Additionally, disable any extensions that may be causing the issue and reset the VSCode settings to their default values.

Q: What are the next steps if the issue persists?

A: If the issue persists after trying the troubleshooting steps, contact the Daml support team for further assistance. They will be able to provide additional guidance and support to help resolve the issue.

Conclusion

The Daml LSP crash issue in the VSCode plugin is a frustrating problem that can disrupt the development workflow. By understanding the affected Daml versions, bug description, and troubleshooting steps, we can take the necessary steps to resolve the issue and improve the Daml development experience. We hope that this Q&A guide has provided a comprehensive resource to help you troubleshoot and resolve the issue.