Improve CTRF library output

Makefile

@@ -46,7 +46,6 @@ ${TMPDIR}:
 test-r6rs: ${TMPDIR}
 	cd ${TMPDIR} && printf "#!r6rs\n(import (rnrs base) (rnrs control) (rnrs io simple) (rnrs files) (rnrs programs) (srfi :64) (retropikzel ${LIBRARY}))\n" > test-r6rs.sps
 	cat ${TESTFILE} >> ${TMPDIR}/test-r6rs.sps
-	cd ${TMPDIR} && snow-chibi install --impls=generic --always-yes --install-source-dir=. --install-library-dir=. "(srfi 180)"
 	cd ${TMPDIR} && akku install chez-srfi akku-r7rs
 	cd ${TMPDIR} && COMPILE_R7RS=${SCHEME} timeout 120 compile-scheme -I .akku/lib -o test-r6rs test-r6rs.sps
 	cd ${TMPDIR} && timeout 60 ./test-r6rs

retropikzel/ctrf.scm

@@ -111,7 +111,16 @@
               output-file
               (lambda ()
                 (json-write output (current-output-port))))
-            (json-write failed-tests (current-output-port))
+            (when (not (= (vector-length failed-tests) 0))
+              (display "[")
               (newline)
+              (vector-for-each
+                (lambda (failed-test)
+                  (display "  ")
+                  (json-write failed-test)
+                  (newline))
+                failed-tests)
+              (display "]")
+              (newline))
             (exit (+ fail xfail)))))
       runner)))