Filtering Results

Using entryFilter and sourceFilter to filter the results for V8 report

When V8 coverage data collected, it actually contains the data of all entry files, for example:

• dist/main.js
• dist/vendor.js
• dist/something-else.js

We can use entryFilter to filter the entry files. For example, we should remove vendor.js and something-else.js if they are not in our coverage scope.

• dist/main.js

When inline or linked sourcemap exists to the entry file, the source files will be extracted from the sourcemap for the entry file, and the entry file will be removed if logging is not debug.

• src/index.js
• src/components/app.js
• node_modules/dependency/dist/dependency.js

We can use sourceFilter to filter the source files. For example, we should remove dependency.js if it is not in our coverage scope.

• src/index.js
• src/components/app.js

Filter Examples

For example:

const coverageOptions = {
    entryFilter: (entry) => entry.url.indexOf("main.js") !== -1,
    sourceFilter: (sourcePath) => sourcePath.search(/src\//) !== -1
};

Or using minimatch pattern:

const coverageOptions = {
    entryFilter: "**/main.js",
    sourceFilter: "**/src/**"
};

Support multiple patterns:

const coverageOptions = {
    entryFilter: {
        '**/node_modules/**': false,
        '**/vendor.js': false,
        '**/src/**': true
    },
    sourceFilter: {
        '**/node_modules/**': false,
        '**/**': true
    }
};

As CLI args (JSON-like string. Added in: v2.8):

mcr --sourceFilter "{'**/node_modules/**':false,'**/**':true}"

Note, those patterns will be transformed to a function, and the order of the patterns will impact the results:

const coverageOptions = {
    entryFilter: (entry) => {
        if (minimatch(entry.url, '**/node_modules/**')) { return false; }
        if (minimatch(entry.url, '**/vendor.js')) { return false; }
        if (minimatch(entry.url, '**/src/**')) { return true; }
        return false; // else unmatched
    }
};

Using filter instead of entryFilter and sourceFilter

If you don't want to define both entryFilter and sourceFilter, you can use filter instead. (Added in: v2.8)

const coverageOptions = {
    // combined patterns
    filter: {
        '**/node_modules/**': false,
        '**/vendor.js': false,
        '**/src/**': true
        '**/**': true
    }
};