Sergey Bogolepov
2.6 KiB
Code Coverage
Kotlin/Native has a code coverage support that is based on Clang's Source-based Code Coverage.
Please note:
- Currently, support for code coverage in Kotlin/Native is broken and not working out of the box.
If you would like to fix it and need guidance,
please contact us on the public Slack on
#kotlin-nativechannel. - Most of the described functionality might be incorporated into Gradle plugin some day.
Usage
TL;DR
kotlinc-native main.kt -Xcoverage
./program.kexe
llvm-profdata merge program.kexe.profraw -o program.profdata
llvm-cov report program.kexe -instr-profile program.profdata
Compiling with coverage enabled
There are 2 compiler flags that allows to generate coverage information:
-Xcoverage. Generate coverage for immediate sources.-Xlibrary-to-cover=<path>. Generate coverage for specifiedklib. Note that library also should be either linked via-library/-lcompiler option or be a transitive dependency.
Running covered executable
After the execution of the compiled binary (ex. program.kexe) program.kexe.profraw will be generated.
By default it will be generated in the same location where binary was created. The are two ways to override this behavior:
-Xcoverage-file=<path>compiler flag.LLVM_PROFILE_FILEenvironment variable. So if you run your program like this:
LLVM_PROFILE_FILE=build/program.profraw ./program.kexe
Then the coverage information will be stored to the build dir as program.profraw.
Parsing *.profraw
Generated file can be parsed with llvm-profdata utility. Basic usage:
llvm-profdata merge default.profraw -o program.profdata
See command guide for more options.
Creating reports
The last step is to create a report from the program.profdata file.
It can be done with llvm-cov utility (refer to command guide for detailed usage).
For example, we can see a basic report using:
llvm-cov report program.kexe -instr-profile program.profdata
Or show a line-by-line coverage information in html:
llvm-cov show program.kexe -instr-profile program.profdata -format=html > report.html
Sample
Usually coverage information is collected during running of the tests.
Please refer to samples/coverage to see how it can be done.