The tool to run tests inserts a -run TestNameOne|TestNameTwo when ran by clicking the run file tests or the run test hover text in a *_test.go file. (see vscode-go/src/testUtils.ts:375)

This conflicts with user settings supplied -run regex flags, resulting in the error of:
go test: run flag may be set only once

In our project, our tests have suffixes of "_unit", "_acceptance", "_regression", etc... so our user settings file has:

"go.testFlags": [
        "-run",
        "^(.*_unit)$"
    ],

in it so that when tests are run on a file save, only the unit tests run.

Clicking run test results in:

Running tool: /usr/local/go/bin/go test github.com/CompanyName/projectName/packageName -run ^(TestNameOne_unit)$ -run ^(.*_unit)$

go test: run flag may be set only once
run "go help test" or "go help testflag" for more information
Error: Tests failed.

When clicking on the run package tests hover text, no -run regex is inserted by the tool so the command looks like:

Running tool: /usr/local/go/bin/go test -timeout 120s github.com/CompanyName/projectName/packageName -v -run ^(.*_unit)$

and it runs as expected.

It seems to us that there are a few potential solutions here, but we don't want to dictate any solution to you. It might just be easiest to say "Ignore the user settings -run regex commands when the tool is creating its own`

Thank you for your help, please let me know if there is anything else I can provide.
-Dan