Install everything in PREFIX, set EXTRA_PATH to find it there.

--- ./Makefile.in~	2016-02-06 01:29:16.595090365 +0100
+++ ./Makefile.in	2016-02-06 09:29:04.286008931 +0100
@@ -133,9 +133,9 @@
 # require for testing here (like TCLX_LIBRARY).
 #========================================================================

-EXTRA_PATH	= $(top_builddir):$(TCL_BIN_DIR)
+EXTRA_PATH	= $(top_builddir):$(TCL_BIN_DIR):$(libdir)
 #EXTRA_PATH     = $(top_builddir):$(TCL_BIN_DIR):$(TK_BIN_DIR)
-TCLLIBPATH      = $(top_builddir)
+TCLLIBPATH      = $(pkglibdir)
 TCLSH_ENV	= TCL_LIBRARY=`@CYGPATH@ $(TCL_SRC_DIR)/library` \
 		  @LD_LIBRARY_PATH_VAR@="$(EXTRA_PATH):$(@LD_LIBRARY_PATH_VAR@)" \
 		  PATH="$(EXTRA_PATH):$(PATH)" \
 bmit();'>
<option value='koszko' selected='selected'>koszko</option>
<option value='koszko-scripts'>koszko-scripts</option>
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<div class='path'>path: <a href='/guix/log/?id=f80824fe0997f3e5d73ef16b8d42d248ce31cc69'>root</a>/<a href='/guix/log/gnu?id=f80824fe0997f3e5d73ef16b8d42d248ce31cc69'>gnu</a>/<a href='/guix/log/gnu/tests?id=f80824fe0997f3e5d73ef16b8d42d248ce31cc69'>tests</a>/<a href='/guix/log/gnu/tests/base.scm?id=f80824fe0997f3e5d73ef16b8d42d248ce31cc69'>base.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/tests/base.scm?id=f80824fe0997f3e5d73ef16b8d42d248ce31cc69&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-04-13 10:02:46 +0200'>2021-04-13</span></td><td><a href='/guix/commit/gnu/tests/base.scm?id=822eacc6bb0878323e6687d4460a7c53066545e1'>tests: halt: Fix it.</a><span class='msg-avail'>...<span class='msg-tooltip'>This fixes: &lt;https://issues.guix.gnu.org/47727&gt;.  The OCR prompt detection is
failing, so remove it altogether.  It looks like the test doesn't need the
prompt detection delay to work properly.

* gnu/tests/base.scm (run-halt-test): Remove failing OCR detection.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-10-26 16:33:39 +0100'>2020-10-26</span></td><td><a href='/guix/commit/gnu/tests/base.scm?id=572c59a7a1ac94a1fda78fcd2cc37c3e335b297f'>tests: Fix nss-mdns test.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/tests/base.scm (run-nss-mdns-test): Use full "avahi-browse" path.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-09-10 14:59:53 +0200'>2020-09-10</span></td><td><a href='/guix/commit/gnu/tests/base.scm?id=6e71514a2992eed1cfa2306f65ca750d65708bc4'>tests: install: Fix gui-installed-desktop-os-encrypted test.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/tests/base.scm (run-basic-test): Add a 'desktop?' argument. Wait 30
seconds before trying to switch to TTY1 on desktop.
* gnu/tests/install.scm (guided-installation-test): Use 512MiB of RAM and pass
the desktop argument to "run-basic-test".
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-04-07 12:31:36 +0200'>2020-04-07</span></td><td><a href='/guix/commit/gnu/tests/base.scm?id=3302e03ba0edca49347c6a2b215e56bd53a6b113'>services: guix: Add 'set-http-proxy' action.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://bugs.gnu.org/25569&gt;.
Reported by Divan Santana &lt;divan@santanas.co.za&gt;.

* gnu/services/base.scm (shepherd-set-http-proxy-action): New procedure.
(guix-shepherd-service): Add 'actions' field.  Change 'start' to a
lambda; check the value of the "http_proxy" environment variable and
add "http_proxy" and "https_proxy" to #:environment-variables as a
function of that.
* gnu/tests/base.scm (run-basic-test)["guix-daemon set-http-proxy
action", "guix-daemon set-http-proxy action, clear"]: New tests.
* doc/guix.texi (Base Services): Document it.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-04-06 23:56:24 +0200'>2020-04-06</span></td><td><a href='/guix/commit/gnu/tests/base.scm?id=d7113bb655ff80a868a9e624c913f9d23e6c63ad'>services: syslog: Create log files as non-world-readable.</a><span class='msg-avail'>...<span class='msg-tooltip'>Partly fixes &lt;https://bugs.gnu.org/40405&gt;.
Reported by Diego Nicola Barbato &lt;dnbarbato@posteo.de&gt;.

* gnu/services/base.scm (syslog-service-type): Change 'start' method to
set umask to #o137 before spawning syslogd.
* gnu/tests/base.scm (run-basic-test)["/var/log/messages is not
world-readable"]: New test.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-03-05 23:40:22 +0100'>2020-03-05</span></td><td><a href='/guix/commit/gnu/tests/base.scm?id=91ba90c18b9ca3512e3a3ab359119f94f94c5b17'>tests: 'run-basic-test' can enter a root password.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/tests/base.scm (run-basic-test): Add #:root-password and honor it.
</span></span></td><td>Ludovic Courtès</td></tr>