In a previous post, I outlined a method for converting Xcode's code coverage format to a format that Codecov can ingest. This method relied on an open source tool called xcresultparser.

Since writing that post, I've found a new method that is slightly faster and — more importantly — removes the dependency on external tools, instead relying solely on tools included within Xcode's command line tools.

Codecov lists the code coverage formats it natively accepts in its documentation here: Supported Coverage Report Formats. Among the accepted formats is lcov.

Xcode includes a tool called llvm-cov, which can be called from the command line using xcrun:

xcrun llvm-cov

llvm-cov's has a number of subcommands, but the one we're interested in is export. This command does the conversion we need from Xcode's native format to the more interoperable lcov format.

1. Run the Tests

In order to use the export command, we'll need to gather a couple dependencies that need to be passed to it in order to do the conversion.

First, we need to know the location of the DerivedData directory. In order to isolate your test results to just the tests that you care about, I recommend using the -derivedDataPath flag to specify the location of DerivedData explicitly in whatever xcodebuild command you use to run your tests. (I usually just put it at the present working directory for easy future reference.)

xcrun xcodebuild test -derivedDataPath ./DerivedData ...

2. Convert the Coverage Data

You'll need to fill in the app name in the following command, but the general process is as follows:

xcrun llvm-cov export \
	--format lcov \
	--ignore-filename-regex "DerivedData" \
	--instr-profile DerivedData/Build/ProfileData/*/Coverage.profdata \
	DerivedData/Build/Products/Debug-iphonesimulator/<app_name>.app/<app_name>.debug.dylib \
	> coverage.info

If needed, you can also post-process the coverage.info file to strip the current working directory prefix from absolute source file paths, which can be done with a simple sed command like so:

sed -i '' "s|SF:$(pwd)/|SF:|" coverage.info

Conclusion

This method is slightly faster than the xcresultparser method, but the biggest win is the fact that it removes a dependency on a tool, which is always welcome.