Fix calculation of branch coverage when a class has no branches.

[jkrumow]

Branch-rate should be 1.0 when a class has no branches since there is only one code path which can be taken.

Something I have noticed lately.

Cheers
tarbrain

[marklarr]

Thanks @tarbrain! I'll have a look at this soon.

[jkrumow]

According to Cobertura's metrics and implementation a file without lines / branches will have a rate of 1.0 (100%):

https://github.com/cobertura/cobertura/blob/master/cobertura/src/main/java/net/sourceforge/cobertura/coveragedata/CoverageDataContainer.java (lines 115 , 160)

https://github.com/cobertura/cobertura/blob/master/cobertura/src/main/java/net/sourceforge/cobertura/coveragedata/ClassData.java (lines 164, 220)

I've made the changes only in slather/coverage_service/cobertura_xml_output.rb so coverage_file.rb remains unaffected.

[marklarr]

The gem's current version is 1.5.3, I think we want to move these changes to the next release?

[jkrumow]

done.

[marklarr]

Cool! Sorry for the wait, @tarbrain