Introduction

Sometimes certain sections of code are not feasible to test. To name a few, this includes:

• Code that's platform-specific, thus not testable in the environment where the coverage data is collected.
• Code that does sanity checks and is expected to be not covered.
• Code that's not feasible or too difficult to test. It's not cost-effective to test this portion of code for whatever reason.

To help you with these sections, CoverStory supports some special markings to tell it to ignore that code. These NF (non-feasible) markings should be used responsibly. They're added to help you eliminate noise in the data. You should aim for 100% coverage if you use this marking in your code.

Details

To mark a single line as non-feasible, add a // COV_NF_LINE to the end of the line. To mark a block as non-feasible, surround it with // COV_NF_START and // COV_NF_END.

Some code samples:

• Line-based markers:

It excludes a particular line from coverage percentage calculation. It takes effect only when the given line is instrumented.

   if (all_hell_breaks_loose) {
      NSLog(@"The sky is falling! The sky is falling!");      // COV_NF_LINE
   }

• Range-based markers:

It excludes the section of code falling into the range of the marker. The markers are inclusive, but don't nest.

   #ifdef OS_WINDOWS   // COV_NF_START
     do task a;
     ...
     do task z;
   #endif              // COV_NF_END

Xcode Script

There is a python script for the Xcode script menu named MarkAsCodeCoverageNonFeasible which greatly simplifies marking chunks of code as non-feasible for code coverage. Read the script for installation instructions.