The Cloud Spanner Emulator is part of the bundled gcloud, to make sure it's installed:
cd infra gclient runhooks eval `./go/env.py` which gcloud # should show bundled gcloud gcloud components list # should see cloud-spanner-emulator is installed
If you are a Google employee, follow go/docker-for-mac first.
From command line, first set environment variables:
export INTEGRATION_TESTS=1 export SPANNER_EMULATOR=1
Then run go test as usual.
Note: If you run tests on Mac, please start Docker Desktop before running tests.