Test coverage

The Connect IQ SDK can run unit tests but can’t tell you what they cover. rafiki coverage adds that by recording which functions run during your tests.

Note

Coverage is per function. A function counts as covered as soon as it runs, however much of it runs.

Run it

With the simulator running and monkeyc and monkeydo from the SDK on your PATH, run this from anywhere in the project:

rafiki coverage test -d fr965 -y developer_key.der

It builds the tests, runs them in the simulator and prints how many functions in each file ran, along with the ones that didn’t:

╭─────────────────────┬─────────┬──────────────────╮
│ FILE                ┆ COVERED ┆ MISSED           │
╞═════════════════════╪═════════╪══════════════════╡
│ source/ClockView.mc ┆ 2/3     ┆ ClockView.onHide │
├╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┤
│ source/Format.mc    ┆ 1/2     ┆ formatDate       │
╰─────────────────────┴─────────┴──────────────────╯

TOTAL 3/5 functions executed (60%)

The command fails when the build fails or a test fails. A failing test still prints the table, since the code did run.

A few flags are useful here:

• --start-simulator starts the simulator if it isn’t running.
• --out-format lcov --out coverage.info writes an LCOV report for tools like genhtml, Codecov or the VS Code Coverage Gutters extension.
• --dry-run prints the monkeyc and monkeydo commands instead of running them.
• Anything after -- is passed on to monkeyc, like -- -O 3.

Run rafiki coverage test --help for the full list.

What’s left out

Functions annotated with (:test) or (:release) aren’t counted, since test code shouldn’t cover itself and tests don’t run release builds. Skip more annotations with --exclude-annotation.

Run each step yourself

test is a shortcut for three steps, which you can also run one at a time, for example in CI:

rafiki coverage instrument
monkeyc -f bin/coverage/coverage.jungle -d fr965 -o bin/coverage/cov.prg -y developer_key.der --unit-test
monkeydo bin/coverage/cov.prg fr965 -t | rafiki coverage report -

How it works explains what each step does.