x/tools/gopls: add a way to provide gopls settings for the built-in MCP server

[IceTea233]

Currently there isn't an obvious way to write gopls settings listed in the official document as suggested through the interfaces provided by the clients (editors like VS Code for example).

I wondered if it is reasonable by design but thought some of the settings would be useful if they can also be set for the built-in MCP server. E.g. env and directoryFilters of the Build setting.

[gabyhelp]

Related Issues

• x/tools/gopls: make it easier to query supported settings #62573
• x/tools/gopls: reconsider and restructure setting parameter names #43101 (closed)
• x/tools/gopls: consider avoiding the workspace/configuration request #57329
• x/tools/gopls: provide means by which client can set session options post Initialize #39050 (closed)
• x/tools/cmd/gopls: define fields for "initializationOptions" #30578 (closed)

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[adonovan]

(Removing proposal metadata since this is just a gopls feature request, and a reasonable one.)

[adonovan]

cc: @h9jiang

[h9jiang]

Thanks for raising this.

I think this is a reasonable feature request, especially the one you mentioned here, those are pretty common settings that controls how gopls are analyzing the workspace.

We can maybe prioritize the MCP work in the coming months including this and file watcher experiments...