These are instructions for collecting code coverage data for android instrumentation and JUnit tests. For Clang(C++) code coverage refer to clang coverage.
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In order to use JaCoCo code coverage, we need to create build time pre-instrumented class files and runtime .exec files. Then we need to process them using the build/android/generate_jacoco_report.py script.
- Use the following GN build arguments:
target_os = "android"
use_jacoco_coverage = true
Now when building, pre-instrumented files will be created in the build directory.
-
Run tests, with option
--coverage-dir <directory>
, to specify where to save the .exec file. For example, you can run chrome JUnit tests:out/Debug/bin/run_chrome_junit_tests --coverage-dir /tmp/coverage
. -
The coverage results of JUnit and instrumentation tests will be merged automatically if they are in the same directory.
- Now we have generated .exec files already. We can create a JaCoCo HTML/XML/CSV
report using
generate_jacoco_report.py
, for example:
build/android/generate_jacoco_report.py \
--format html \
--output-dir /tmp/coverage_report/ \
--coverage-dir /tmp/coverage/ \
--sources-json-dir out/Debug/ \
Then an index.html containing coverage info will be created in output directory:
[INFO] Loading execution data file /tmp/coverage/testTitle.exec.
[INFO] Loading execution data file /tmp/coverage/testSelected.exec.
[INFO] Loading execution data file /tmp/coverage/testClickToSelect.exec.
[INFO] Loading execution data file /tmp/coverage/testClickToClose.exec.
[INFO] Loading execution data file /tmp/coverage/testThumbnail.exec.
[INFO] Analyzing 58 classes.
- For XML and CSV reports, we need to specify
--output-file
instead of--output-dir
since only one file will be generated as XML or CSV report.
build/android/generate_jacoco_report.py \
--format xml \
--output-file /tmp/coverage_report/report.xml \
--coverage-dir /tmp/coverage/ \
--sources-json-dir out/Debug/ \
or
build/android/generate_jacoco_report.py \
--format csv \
--output-file /tmp/coverage_report/report.csv \
--coverage-dir /tmp/coverage/ \
--sources-json-dir out/Debug/ \
- If generating coverage and there are duplicate class files, as can happen
when generating coverage for downstream targets, use the
--include-substr-filter
option to choose jars in the desired directory. Eg. for generating coverage report for Clank internal repo
build/android/generate_jacoco_report.py --format html \
--output-dir /tmp/coverage_report/ --coverage-dir /tmp/coverage/ \
--sources-json-dir out/java_coverage/ \
--include-substr-filter obj/clank