* guix/utils.scm (target-x86-32?, target-x86-64?): New predicates.
* tests/utils.scm ("target-x86-32?", "target-x86-64?"): New tests.

Signed-off-by: Mathieu Othacehe <othacehe@gnu.org>

* guix/utils.scm (target-linux?): New predicate.
* tests/utils.scm
  ("target-linux?"): Test it.
  ("target-mingw?"): Also test ‘target-mingw?’.

Signed-off-by: Mathieu Othacehe <othacehe@gnu.org>

* guix/utils.scm (string-distance): New procedure.
(string-closest): New procedure.
* tests/utils.scm ("string-distance", "string-closest"): New tests.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

* guix/utils.scm (version-unique-prefix): New procedure.
* tests/utils.scm ("version-unique-prefix"): New test.

* guix/utils.scm (lzip-port): Return a single value.
(zstd-port): New procedure.
(decompressed-port, compressed-output-port): Add 'zstd' case.
* tests/utils.scm (test-compression/decompression): Test 'zstd' when
the (zstd) module is available.

This procedure was unused except in one test.

* guix/utils.scm (compressed-port): Remove.
* tests/utils.scm (test-compression/decompression): Rewrite to use
'compressed-output-port' instead.

* Makefile.am (MODULES): Remove guix/zlib.scm and guix/lzlib.scm,
(SCM_TESTS): remove tests/zlib.scm, tests/lzlib.scm.
* build-aux/build-self.scm (make-config.scm): Remove unused %libz variable.
* configure.ac: Remove LIBZ and LIBLZ variables and check instead for
Guile-zlib and Guile-lzlib.
* doc/guix.texi ("Requirements"): Remove zlib requirement and add Guile-zlib
and Guile-lzlib instead.
* gnu/packages/package-management.scm (guix)[native-inputs]: Add "guile-zlib"
and "guile-lzlib",
[inputs]: remove "zlib" and "lzlib",
[propagated-inputs]: ditto,
[arguments]: add "guile-zlib" and "guile-lzlib" to Guile load path.
* guix/config.scm.in (%libz, %liblz): Remove them.
* guix/lzlib.scm: Remove it.
* guix/man-db.scm: Use (zlib) instead of (guix zlib).
* guix/profiles.scm (manual-database): Do not stub (guix config) in imported
modules list, instead add "guile-zlib" to the extension list.
* guix/scripts/publish.scm: Use (zlib) instead of (guix zlib) and (lzlib)
instead of (guix lzlib),
(string->compression-type, effective-compression): do not check for zlib and
lzlib availability.
* guix/scripts/substitute.scm (%compression-methods): Do not check for lzlib
availability.
* guix/self.scm (specification->package): Add "guile-zlib" and "guile-lzlib"
and remove "zlib" and "lzlib",
(compiled-guix): remove "zlib" and "lzlib" arguments and add guile-zlib and
guile-lzlib to the dependencies, also do not pass "zlib" and "lzlib" to
"make-config.scm" procedure,
(make-config.scm): remove "zlib" and "lzlib" arguments as well as %libz and
%liblz variables.
* guix/utils.scm (lzip-port): Use (lzlib) instead of (guix lzlib) and do not
check for lzlib availability.
* guix/zlib.scm: Remove it.
* m4/guix.m4 (GUIX_LIBZ_LIBDIR, GUIX_LIBLZ_FILE_NAME): Remove them.
* tests/lzlib.scm: Use (zlib) instead of (guix zlib) and (lzlib)
instead of (guix lzlib), and do not check for zlib and lzlib availability.
* tests/publish.scm: Ditto.
* tests/substitute.scm: Do not check for lzlib availability.
* tests/utils.scm: Ditto.
* tests/zlib.scm: Remove it.

Prior to this change the added test fails for me locally at byte
1024. It might depend on some default buffer sizes.

Fixes <https://bugs.gnu.org/35863>.

* tests/utils.scm ("canonical-newline-port-1024"): Add test.
* guix/utils.scm (canonical-newline-port): Correct comments on CR/LF.
Remove CR even when they're at the end of the buffer.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

* guix/utils.scm (lzip-port): New procedure.
(decompressed-port, compressed-port, compressed-output-port): Add 'lzip
case.
* tests/utils.scm <top level>: Call 'test-compression/decompression' for
'lzip as well.

* tests/utils.scm (test-compression/decompression): New procedure.
<top level>: Call it for both 'xz and 'gzip.