- Create a Github action for your SwiftPM project.
- Add a step to build:
swift build - Add a step to run tests:
swift test --enable-code-coverage - Fetch coverage value (see below)
- Write coverage value to gist and generate badge from it
For step #4, we need to do some sleuthing and digging around into artifacts created by the Swift toolchain. First, we need to find the location of the XCTest bundle that step #3 generated and save it in an environment variable:
XCTEST_PATH="$(find . -name '*.xctest')"
Next, we run llvm-cov to generate a report using the contents of the bundle and another file that contains the
code coverage values:
xcrun llvm-cov report ${XCTEST_PATH}/Contents/MacOS/*PackageTests -instr-profile .build/debug/codecov/default.profdata -ignore-filename-regex='.build/|Tests/'
The above generates a report like so:
Filename Regions Missed Regions Cover Functions Missed Functions Executed Lines Missed Lines Cover Branches Missed Branches Cover
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
DVV.swift 42 8 80.95% 26 4 84.62% 58 6 89.66% 0 0 -
Dot.swift 2 0 100.00% 2 0 100.00% 2 0 100.00% 0 0 -
DotVector.swift 41 1 97.56% 16 1 93.75% 63 1 98.41% 0 0 -
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
TOTAL 85 9 89.41% 44 5 88.64% 123 7 94.31% 0 0 -
We are only interested in the last line, so we will pipe the above command into a tail -1 process, and we will use the Bash shell's
set command to parse the line and get the 4th item that is the percentage. This is then saved for a future action step.
The whole step is for generating the coverage percentage value is this:
XCTEST_PATH="$(find . -name '*.xctest')"
set -- $(xcrun llvm-cov report ${XCTEST_PATH}/Contents/MacOS/*PackageTests -instr-profile .build/debug/codecov/default.profdata -ignore-filename-regex='.build/|Tests/' | tail -1)
echo "$4" > .build/debug/codecov/percentage.txt
echo "PERCENTAGE=$4" >> $GITHUB_ENV
Finally, with an appropriate Github GIST setup, we can generate a badge that shows the coverage value. The step below runs
the dynamic-badges-action action that takes a Gist ID and filename, updates it with the value taken from the environment
set in the previous stage, and builds a badge called "Coverage" with its value.
- name: Create Coverage Badge
uses: schneegans/[email protected]
with:
auth: ${{ secrets.GIST_UPDATE }}
gistID: ad941184ed256708952a2057fc5d7bb4
filename: swift-math-parser-coverage.json
label: Coverage
message: ${{ env.PERCENTAGE }}
color: success