search: make better parser test output
Created by: rvantonder
Stacked on https://github.com/sourcegraph/sourcegraph/pull/37656
deduplicates JSON print functions and puts verbose test output in testdata files
Test plan
Semantics-preserving
Created by: rvantonder
Stacked on https://github.com/sourcegraph/sourcegraph/pull/37656
deduplicates JSON print functions and puts verbose test output in testdata files
Semantics-preserving