"go test -bench B ." writes files into testdata

[dr2chase]

This is anti-recommended, and causes spurious failures when tests and run using Go modules because all the source code is checked out read-only ( https://golang.org/ref/mod#module-cache also golang/go#28386).

Failure, observed with read-only testdata:

% go test -bench B .
--- FAIL: BenchmarkBindata
    benchmark_test.go:47: open testdata/assets/sf-fzlmnmzwlrm7hq2x.tmp: permission denied
FAIL
exit status 1
FAIL	github.com/kevinburke/go-bindata	0.793s
FAIL

Or, in a directory containing a go.mod:

go test github.com/kevinburke/go-bindata -bench B -run nope
--- FAIL: BenchmarkBindata
    benchmark_test.go:47: open testdata/assets/sf-jwvtvw26u2y72aov.tmp: permission denied
FAIL
exit status 1
FAIL	github.com/kevinburke/go-bindata	0.635s
FAIL

-run nope was specified above because of problems with other tests; this specific failure concerns running benchmarks, which is how I found this.

[kevinburke]

Thanks, I'll take a look at the patch later today.