solidity-coverage

18 20 21 26

Code coverage for Solidity testing

!coverage example22

• For more details about what this is, how it works and potential limitations,

see the accompanying article16.

• solidity-coverage is Solcover17

Requirements

• Hardhat >= 2.11.0

Install

$ yarn add solidity-coverage --dev

Require the plugin in hardhat.config.js (Hardhat docs26)

require('solidity-coverage')

Or, if you are using TypeScript, add this to your hardhat.config.ts:

import 'solidity-coverage'

Resources:

• 0.8.0 release notes31

Run

npx hardhat coverage [command-options]

Trouble shooting

Missing or unexpected coverage? Make sure you're using the latest plugin version and run:

$ npx hardhat clean
$ npx hardhat compile
$ npx hardhat coverage

Typescript compilation errors?

$ npx hardhat compile
$ TS_NODE_TRANSPILE_ONLY=true npx hardhat coverage

Weird test failures or plugin conflicts?

# Setting the `SOLIDITY_COVERAGE` env variable tells the coverage plugin to configure the provider
# early in the hardhat task cycle, minimizing conflicts with other plugins or `extendEnvironment` hooks

$ SOLIDITY_COVERAGE=true npx hardhat coverage

Additional Help

• FAQ1007
• Advanced Topics1005

Command Options

| Option | Example | Description | |--------------|------------------------------------|--------------------------------| | testfiles | --testfiles "test/registry/*.ts" | Test file(s) to run. (Globs must be enclosed by quotes and use globby matching patterns38)| | sources | --sources myFolder or --sources myFile.sol | Path to single folder or file to target for coverage. Path is relative to Hardhat's paths.sources (usually contracts/) | | solcoverjs | --solcoverjs ./../.solcover.js | Relative path from working directory to config. Useful for monorepo packages that share settings. (Path must be "./" prefixed) | | matrix | --matrix | Generate a JSON object that maps which mocha tests hit which lines of code. (Useful as an input for some fuzzing, mutation testing and fault-localization algorithms.) More...39|
Advanced use14

Config Options

Additional options can be specified in a .solcover.js config file located in the root directory of your project.
Example:

module.exports = {
  skipFiles: ['Routers/EtherRouter.sol']
};

| Option | Type | Default | Description | | ------ | ---- | ------- | ----------- | | skipFiles | Array | [] | Array of contracts or folders (with paths expressed relative to the contracts directory) that should be skipped when doing instrumentation.(ex: [ "Routers", "Networks/Polygon.sol"]) :warning: RUN THE HARDHAT CLEAN COMMAND AFTER UPDATING THIS | | modifierWhitelist | String | [] | List of modifier names (ex: onlyOwner) to exclude from branch measurement. (Useful for modifiers which prepare something instead of acting as a gate.)) | | mocha | Object | { } | Mocha options3 to merge into existing mocha config. grep and invert are useful for skipping certain tests under coverage using tags in the test descriptions. More...24| | measureStatementCoverage | boolean | true | Computes statement (in addition to line) coverage. More...34 | | measureFunctionCoverage | boolean | true | Computes function coverage. More...34 | | measureModifierCoverage | boolean | true | Computes each modifier invocation as a code branch. More...34 | | :printer: OUTPUT | | | | | matrixOutputPath | String | ./testMatrix.json | Relative path to write test matrix JSON object to. More...39| | mochaJsonOutputPath | String | ./mochaOutput.json | Relative path to write mocha JSON reporter object to. More...39| | abiOutputPath | String | ./humanReadableAbis.json | Relative path to write diff-able ABI data to | | istanbulFolder | String | ./coverage | Folder location for Istanbul coverage reports. | | istanbulReporter | Array | ['html', 'lcov', 'text', 'json'] | Istanbul coverage reporters2 | | silent | Boolean | false | Suppress logging output | | :recycle: WORKFLOW HOOKS | | | | | onServerReady14 | Function | | Hook run after server is launched, before the tests execute. Useful if you need to use the Oraclize bridge or have setup scripts which rely on the server's availability. More...23 | | onPreCompile14 | Function | | Hook run after instrumentation is performed, before the compiler is run. Can be used with the other hooks to be able to generate coverage reports on non-standard / customized directory structures, as well as contracts with absolute import paths. More...23 | | onCompileComplete14 | Function | | Hook run after compilation completes, before tests are run. Useful if you have secondary compilation steps or need to modify built artifacts. More...23| | onTestsComplete14 | Function | | Hook run after the tests complete, before Istanbul reports are generated. More...23| | onIstanbulComplete14 | Function | | Hook run after the Istanbul reports are generated, before the coverage task completes. Useful if you need to clean resources up. More...23| | :warning: DEPRECATED | | | | | configureYulOptimizer | Boolean | false | (Deprecated since 0.8.7) Setting to true should resolve "stack too deep" compiler errors in large projects using ABIEncoderV2 | | solcOptimizerDetails | Object | undefined |(Deprecated since 0.8.7)) Must be used in combination with configureYulOptimizer. Allows you configure solc's optimizer details1001. Useful if the default remedy for stack-too-deep errors doesn't work in your case (See FAQ: Running out of stack1002 ). |
Advanced use14

Viewing the reports:

• You can find the Istanbul reports written to the ./coverage/ folder generated in your root directory.

API

Solidity-coverage's core methods and many utilities are available as an API.

const CoverageAPI = require('solidity-coverage/api');

Documentation available here28.

Detecting solidity-coverage from another task

If you're writing another plugin or task, it can be helpful to detect whether coverage is running or not. The coverage plugin sets a boolean variable on the globally injected hardhat environment object for this purpose.

hre.__SOLIDITY_COVERAGE_RUNNING === true

Example reports

• openzeppelin-solidity10

Funding

You can help fund solidity-coverage development through DRIPS1008. It's a public goods protocol which helps distribute money to packages in your dependency tree. (It's great, check it out.)

Contribution Guidelines

Contributions are welcome! If you're opening a PR that adds features or options please consider writing full unit tests11 for them. (We've built simple fixtures for almost everything and are happy to add some for your case if necessary).
Set up the development environment with:

$ git clone https://github.com/sc-forks/solidity-coverage.git
$ yarn