tests: Skip network-dependent tests when the network is unreachable.

* tests/builders.scm (network-reachable?): New variable.
  ("url-fetch", "gnu-build"): Skip unless NETWORK-REACHABLE?.
* tests/derivations.scm (%coreutils): Check for network access.
  ("build-expression->derivation with one input"): Skip when %COREUTILS
  is #f.
* tests/guix-package.sh: Skip installation of GNU Make when the network
  is unreachable.
* tests/packages.scm ("GNU Make, bootstrap"): Likewise.
* tests/union.scm ("union-build"): Likewise.

tests: base32: Work around `system*' bug.

* tests/base32.scm (%nix-hash): When `getenv' returns the empty string,
  ignore it.
  (%have-nix-hash?): New variable.  Update `test-skip' clause to use it.

Merge branch 'master' into nix-integration

Conflicts:
	guix/store.scm

store: Add GC-related operations.

* guix/store.scm (gc-action): New enumerate type.
  (read-long-long, read-string-list, write-store-path,
  write-store-path-list, read-store-path-list): New procedures.
  (write-arg): Add support for `store-path' and `store-path-list'.
  (read-arg): Add support for `store-path-list'.
  (define-operation): Add support for multiple-value returns.
  (run-gc, live-paths, dead-paths, collect-garbage, delete-paths): New
  procedures.
  (%long-long-max): New macro.
* tests/store.scm: New file.
* Makefile.am (TESTS): Add it.

build: Update skip count in `tests/derivations.scm'.

* tests/derivations.scm: When %STORE if #f, skip 11 tests.

build: Run all the tests against the just-built daemon.

* test-env.in: New file.
* configure.ac: Add it to `AC_CONFIG_FILES' and `commands-exec'.
* config-daemon.ac: Set and substitute `GUIX_TEST_ROOT'.
* Makefile.am (SCM_LOG_COMPILER, SH_LOG_COMPILER): Use it in lieu of
  `pre-inst-env'.
* daemon.am (test_root): Remove
  (AM_TESTS_ENVIRONMENT): Remove `TEST_ROOT'.
  (clean-local): Use $(GUIX_TEST_ROOT); make files writable before
  removing them.guix_test_root
* tests/guix-daemon.sh: Remove `NIX_' variable settings; don't launch
  `guix-daemon'.

tests: Remove hard-coded /nix/store.

* tests/utils.scm ("store-path-package-name"): Use (%store-prefix)
  instead of a hard-coded "/nix/store".

daemon: Add `list-runtime-roots' script.

* nix/scripts/list-runtime-roots.in: New file.
* config-daemon.ac: Add `AC_CONFIG_FILES' invocation for it.
* daemon.am (nodist_pkglibexec_SCRIPTS): New variable.
  (AM_TESTS_ENVIRONMENT): Define `top_builddir'.
* tests/guix-daemon.sh: Export `NIX_ROOT_FINDER'.
* nix/sync-with-upstream: Substitute the path to the root finder in
  libstore/gc.cc.

daemon: Add test.

* daemon.am (test_root, AM_TESTS_ENVIRONMENT): New variables.
  (clean-local): New target.
* tests/guix-daemon.sh: New file.

Merge branch 'master' into nix-integration

derivations: Fix erroneous call to `add-to-store' for local files as input.

* guix/derivations.scm (derivation)[inputs]: Fix typo in call to
  `add-to-store'.
* tests/derivations.scm ("derivation with local file as input"): New test.
* tests/packages.scm ("trivial with local file as input"): New test.

guix-package: Extract version strings when installing a direct store path.

* guix-package.in (guix-package)[process-actions]: Extract the version
  string from store paths.
* tests/guix-package.sh: Adjust accordingly.

guix-package: Add `--list-available'.

* guix-package.in (show-help, %options): Add `--list-available'.
  (guix-package)[process-query]: Add support for `--list-available'.
* doc/guix.texi (Invoking guix-package): Document it.
* tests/guix-package.sh: Add test.

* guix/ui.scm (location->string): New procedure.
* guix/utils.scm: Export <location>.

distro: Add `fold-packages'.

* distro.scm (fold-packages): New procedure.
  (find-packages-by-name): Use it instead of hand-written traversal;
  remove `package?' checks from `right-package?'.
* tests/packages.scm ("fold-packages"): New test.

guix-package: Add `--list-installed'.

* guix-package.in (show-help, %options): Add `--list-installed'.
  (guix-package): Move main body to...
  [process-actions]: ... here.  New internal procedure.
  [process-query]: New procedure.
* tests/guix-package.sh: Add tests for `--list-installed'.
* doc/guix.texi (Invoking guix-package): Document it.

guix-download: Use code from (guix build download).

* guix-download.in (http-fetch, ftp-fetch): Remove.
  (fetch-and-store): Replace `uri' parameter with `name', for the output
  file name.  Redirect the output of `fetch' to the error port.
  (guix-download): Call `url-fetch' for all URI schemes except `file'.
  Handle PATH equal to #f.
* guix/download.scm: Export `%mirrors'.
* tests/guix-download.sh: Change erroneous URL, because URLs at
  example.com are all valid redirections.

guix-download: Add support for file:// URIs.

* guix-download.in (fetch-and-store): New procedure.
  (guix-download): Use it to compute PATH.  Call `add-to-store' when
  a `file' URI scheme is used.
* Makefile.am (AM_TESTS_ENVIRONMENT): New variable.
* tests/guix-download.sh: Add test.

guix-download: Gracefully handle invalid URIs.

* guix-download.in (guix-download): Error out when `string->uri'
  returns #f.  Use `leave' when the scheme is unknown.
* tests/guix-download.sh: Add tests.

tests: Make sure to use the bootstrap Guile.

* tests/builders.scm ("url-fetch", "gnu-build"): Pass `url-fetch'
  #:guile %BOOTSTRAP-GUILE.

tests: Remove extraneous test.

* tests/derivations.scm ("build-expression->derivation for fixed-output
  derivation"): Remove test.  It is redundant with that in builders.scm,
  and doesn't work out of the box with the statically-linked
  %BOOTSTRAP-GUILE.