test_format wasn't actually checking output of astyle

It was only checking the return code, but astyle was always returning 0. 
Changed to parse the output and look for the string "Formatted"

crypto_kem/frodokem1344shake/clean/util.c

@@ -13,7 +13,7 @@
 #define min(x, y) (((x) < (y)) ? (x) : (y))
 
 uint16_t PQCLEAN_FRODOKEM1344SHAKE_CLEAN_LE_TO_UINT16(const uint16_t n) {
-    return (((uint8_t *) &(n))[0] | (((uint8_t *) &(n))[1] << 8));
+    return (((uint8_t *) &n)[0] | (((uint8_t *) &n)[1] << 8));
 }
 
 uint16_t PQCLEAN_FRODOKEM1344SHAKE_CLEAN_UINT16_TO_LE(const uint16_t n) {

crypto_kem/frodokem640shake/clean/util.c

@@ -13,7 +13,7 @@
 #define min(x, y) (((x) < (y)) ? (x) : (y))
 
 uint16_t PQCLEAN_FRODOKEM640SHAKE_CLEAN_LE_TO_UINT16(const uint16_t n) {
-    return (((uint8_t *) &(n))[0] | (((uint8_t *) &(n))[1] << 8));
+    return (((uint8_t *) &n)[0] | (((uint8_t *) &n)[1] << 8));
 }
 
 uint16_t PQCLEAN_FRODOKEM640SHAKE_CLEAN_UINT16_TO_LE(const uint16_t n) {

crypto_kem/frodokem976shake/clean/util.c

@@ -13,7 +13,7 @@
 #define min(x, y) (((x) < (y)) ? (x) : (y))
 
 uint16_t PQCLEAN_FRODOKEM976SHAKE_CLEAN_LE_TO_UINT16(const uint16_t n) {
-    return (((uint8_t *) &(n))[0] | (((uint8_t *) &(n))[1] << 8));
+    return (((uint8_t *) &n)[0] | (((uint8_t *) &n)[1] << 8));
 }
 
 uint16_t PQCLEAN_FRODOKEM976SHAKE_CLEAN_UINT16_TO_LE(const uint16_t n) {

test/test_format.py

@@ -13,11 +13,12 @@ def check_format(implementation: pqclean.Implementation):
     helpers.ensure_available('astyle')
     cfiles = implementation.cfiles()
     hfiles = implementation.hfiles()
-    helpers.run_subprocess(['astyle',
+    result = helpers.run_subprocess(['astyle',
                     '--dry-run',
                     '--options=../.astylerc',
                     *cfiles,
                     *hfiles])
+    assert(not('Formatted' in result))
 
 
 if __name__ == "__main__":