Raise ValueError if program is invalid

2 files changed, 10 insertions, 1 deletions

diff --git a/jq.pyx b/jq.pyx
index 447eeb1..604363a 100644
--- a/jq.pyx
+++ b/jq.pyx
@@ -67,6 +67,9 @@ def _string_to_strings(char* program, char* input):
     # TODO: error if !compiled
     cdef int compiled = jq_compile(jq, program)
     
+    if not compiled:
+        raise ValueError("program was not valid")
+    
     cdef jv_parser parser
     jv_parser_init(&parser)
     # TODO: is len a suitable replacement for strlen (unicode)?
diff --git a/tests/jq_tests.py b/tests/jq_tests.py
index 6e9066b..edc6cb4 100644
--- a/tests/jq_tests.py
+++ b/tests/jq_tests.py
@@ -1,4 +1,4 @@
-from nose.tools import istest, assert_equal
+from nose.tools import istest, assert_equal, assert_raises
 
 from jq import jq
 
@@ -57,3 +57,9 @@ def output_elements_are_separated_by_newlines_when_there_are_multiple_inputs():
         "2\n3\n4",
         str(jq(".+1").transform_string("1\n2\n3"))
     )
+
+
+@istest
+def value_error_is_raised_if_program_is_invalid():
+    # TODO: should raise in just jq()
+    assert_raises(ValueError, lambda: jq("!").transform_string("[1, 2, 3]"))