test: print json file

Author: 0xc0170

.travis.yml

@@ -68,7 +68,9 @@ matrix:
             git diff --name-only --diff-filter=d FETCH_HEAD..HEAD \
               | ( grep '.\(c\|cpp\|h\|hpp\)$' || true ) \
               | while read file; do cp --parents "${file}" SCANCODE; done
+        - git diff --name-only --diff-filter=d FETCH_HEAD..HEAD
         - scancode -l --json-pp scancode.json SCANCODE
+        - cat scancode.json
         - python ./tools/test/travis-ci/scancode.py -f scancode.json
 
     - <<: *basic-vm