Fix output testing failing silently

Inline output tests in .travis.yml as well.

Author: natanlao

.travis.yml

@@ -22,4 +22,7 @@ script:
 # Test that notebooks run successfully
 - treon
 # Naive test to check that output committed with notebook-
-- find . -name "*.ipynb" -exec sh test/test_output.sh "{}" \;
+- >-  # carefully escaped because yaml is picky
+  find . -name "*.ipynb" \
+         -exec test $(grep -oc '"outputs": ' "{}") -eq $(grep -oc '"cell_type": "code"' "{}") \; \
+  || exit 1

test/README.md

@@ -12,14 +12,13 @@ on Travis.
 
 The tests also check if output is committed with the notebook (which it should be).
 This test is naive - it tests if the number of code cells in a notebook is equal to
-the number of cell outputs in the same notebook.
+the number of cell outputs in the same notebook. (See `.travis.yml`.)
 
 ## Structure
 
     .
     ├── README.md               You are here!
     ├── ignore                  Add a directory to this file (one per line) to skip during testing
-    ├── test_output.sh          Tests that output has been committed with the notebook.
     ├── requirements-dev.txt    Dependencies for running the tests
     └── requirements.txt        Dependencies for running notebooks (global)