proposal: cmd/go: add go work toggle flag (impossible?)

[switchupcb]

Repost of #57085 because it was closed due to go env -w, but that command doesn't implement the behavior described.

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Developers are required to use environment variables to switch in and out of workspace mode. This means using set GOWORK=off or export GOWORK=off depending on the platform. This in itself is problematic since you have to give out two different instructions (which depend on the user OS). In order to go back into workspace mode, you need to set the GOWORK variable back. If you are dealing with a long path it's time consuming and prone to error.

Toggle Flag

go work toggle

When GOWORK is set, switches the GO Workspace to off.
When GOWORK is off, switches the GO Workspace to current directory.

Flags

-d - Set directory to switch to using relative path.

[ianlancetaylor]

Since you say that this is not go env -w, I don't understand what go work toggle is going to change. It can't change the value of the GOWORK environment variable. And I think it would be very confusing if the GOWORK environment variable were not honored.

[switchupcb]

It can't change the value of the GOWORK environment variable.

Cause the binary won't set the variable of the system. You're right. RIP

[switchupcb]

If go env -w can set the environment variable, why can't this command?

go work toggle -> set GOWORK=off
go work toggle -> set GOWORK=<full current directory here>

How does this fail to honor the environment variable?

[seankhliao]

We're not going to have multiple ways of doing things, especially something like toggle which is unclear in semantics on what happens when you run it without very clear knowledge of the current state of the system.

Such a thing seems better suited as aliases / local scripts to your environment.

[rsc]

This proposal has been added to the active column of the proposals project
and will now be reviewed at the weekly proposal review meetings.
— rsc for the proposal review group

[rsc]

This proposal has been declined as infeasible.
— rsc for the proposal review group