fix some minor errors in unit test example

12-unit-test-eg.org

@@ -74,7 +74,7 @@ Note that we need =types.h= so that we can define the types that ordinarily are
 #ifndef CONTIKI
 typedef unsigned short int uint16_t;
 typedef short int int16_t;
-#if
+#endif
 #+END_SRC
 We don't want to accidentally include these type definitions when Contiki is being used, so =#ifndef= says "only include this bit when CONTIKI is not defined". 
 
@@ -129,11 +129,9 @@ struct decimal *convert_temperature(struct decimal *dp, uint16_t v)
   return dp;
 }
 #+END_SRC
-The above code should fail and when we run =make= when in the =test= directory, we get:
+The above code should fail and when we run =make= from the =test= directory. We get:
 #+BEGIN_SRC
-./test_temp	
 test_temp: test_temp.c:10: test_temp_calc: Assertion `result.integer_part == 66 - 39' failed.
-Makefile:3: recipe for target 'test' failed
 #+END_SRC
 The above says that the test failed at line 10.
 
@@ -168,6 +166,8 @@ struct decimal *convert_temperature(struct decimal *dp, uint16_t v)
   return dp;
 }
 #+END_SRC
+By the way, if you haven't worked it out, the reason why the previous test failed was because we were trying to store a negative number in an unsigned integer. 
+
 When we try this out, we get:
 #+BEGIN_SRC
 test_temp: test_temp.c:17: test_temp_calc: Assertion `result.fractional_part == 60' failed.