* srfi/srfi-64.scm: Export 'test-group'. Call 'cond-expand-provide'. * srfi/srfi-64.upstream.scm: Update to the latest upstream version.
* guix/derivations.scm: Export `read-derivation' and `write-derivation'. * srfi/srfi-64.scm, srfi/srfi-64.upstream.scm: New files, from libchop. * tests/derivations.scm, tests/test.drv: New files.