The Go language server gopls provides support for Go modules.

Add the below in your settings to use Go modules.

"go.useLanguageServer": true

Note: You will be prompted to install the latest stable version of gopls as and when the Go tools team tag a new version as stable.

Extra settings to fine tune gopls are available. Please see the gopls documentation for more information and recommended settings.

• Known issues in VS Code when using gopls

• Troubleshooting and reporting issues

In addition to the Go language server, VS Code extension may use additional Go tools to provide features like code navigation, code completion, build, lint etc. Some tools may not have a good support for Go modules yet. Please report an issue if you encounter problems.

If you don't want to use the language server for any reason, then please know that not all the Go tools that this extension depends on supports Go modules. https://golang.org/issues/24661 is the issue used by the Go tools team to track the update of Go modules support in various Go tools.

FAQ

Can I use the language server when using Go modules?

Yes, you can and this is the path forward for module support in VS Code. Please be aware that the language server itself is in alpha mode with active development in progress. See the section right above this question for details.

Why is code navigation and code completion slow when using Go modules?

Code navigation and code completion definitely works better when using gopls. So, please give that a try.

If you are not using the language server, then this is mostly due to the limitation of the tools that power these features which are godef and gocode respectively. The Go tools team at Google are working on a language server which will be the long term solution for all language features.

Please try out the language server as described in the first section of this page.

If you don't want to use the language server then,

• For slowness in code completion, log an issue in the gocode repo.
• For slowness in code navigation, log an issue in the godef repo or if you chosen to gogetdoc in your settings, then log an issue in the gogetdoc repo

Auto import no longer happens on file save. Why?

If you are not using the language server, this extension uses goreturns tool by default to format your files and auto import missing packages. Since this tool doesn't support modules, the auto import feature on file save no longer works.

Add the setting "go.formatTool": "goimports" and then use Go: Install/Update Tools to install/update goimports as it has recently added support for modules.