30:Td72,signature(signature, { description: md` Documentation template for functions. Extracts the function head from the function passed to **\`fn\`**: - If \`fn\` is a named function, the head is returned as written. If \`name\` was set, it will replace the function name. - If \`fn\` is an arrow function, the declaration will be reformatted and the \`function\` keyword injected. If \`name\` was set, it will be injected as the function name. - Any other argument type is passed through unaltered. **Note:** Javascript may infer the function name from the variable to which a function was first assigned. All settings are optional. Available **\`options\`**: ${Object.entries({ description: 'Rendered as Markdown if a string, otherwise passed through.', example: 'Single value or array of values. String values are formatted as Javascript code, everything else gets passed through.', name: 'Anchor name to link to. Defaults to function name.', scope: 'Class name to scope CSS selectors. Defaults to unique string.', css: 'The theme CSS. If \`scope\` is used, the CSS should start every selector with \`:scope\`. Defaults to \`signature_theme\`.', open: 'Boolean that controls the toggle state of the details wrapper. Set to \`null\` to disable collapsing.', tests: 'Object map of test functions, keyed by test name. Each function receives \`assert(condition, assertion)\` as argument. Async functions are supported.', runTests: 'Boolean or Promise, controls test execution. Set to \`false\` to disable test output.', testRunner: 'Executes tests and builds results markup. See [\`defaultTestRunner()\`](#defaultTestRunner) for details.', }).map(([k,v]) => `- \`${k}:\` ${v}\n`)}`, example: [` // Basic use signature(myUsefulFunc, { description: "It's hard to describe how useful myUsefulFunc is. I use it all the time!" }) `, ` // Tests signature(myTestedFunc, { tests: { 'can retrieve data': async (assert) => { const data = await myTestedFunc().getData(); assert(Array.isArray(data), 'data is array'); assert(data.length, 'data is not empty'); }, 'is this finished?': assert => { assert(myTestedFunc() !== 'todo: implement', 'actually implemented'); }, 'Look, ma! No assert!': () => { try { myTestedFunc().notImplemented() } catch(e) { throw Error(\`Hey signature(), catch this! \${e}\`) }; } }}) `,], tests: { 'signature parsing': assert => { const test = (expect, name, fn) => { const sig = signature(fn, {name, formatter: ({signature:s}) => s.textContent.trim()}); assert(expect === sig, `expected "${expect}", got "${sig}"`); }; {test('function()', undefined, function(){})} {test('function foo1()', undefined, function foo1(){})} {test('function foo2()', 'foo2', function(){})} {test('function()', undefined, ()=>{})} {test('function foo3()', 'foo3', ()=>{})} {test('async function()', undefined, async ()=>{})} {test('async function foo4(a)', 'foo4', async a=>{})} {test('async function foo5()', undefined, async function foo5(){})} {test('async function foo5a()', 'foo5a', async function foo5(){})} {test('async function* foo6()', 'foo6', async function*(){})} {test('function*()', undefined, function * (){})} {test('function(a,b=({foo:"bar"}))', undefined, (a,b=({foo:"bar"}))=>{})} } } })31:T510,function signature(fn, options = {}) { const { name = typeof fn === 'function' && fn.name.length ? fn.name : null, description = null, example = null, open = true, tests = {}, runTests = RUN_TESTS.promise, testRunner = defaultTestRunner, scope = DOM.uid('css-scope').id, css = signature_theme, formatter = defaultFormatter, signatureParser = defaultSignatureParser, } = options; const sig = typeof fn !== 'function' ? fn : signatureParser(fn, name); let testList = null; if(runTests && tests && Object.keys(tests).length) { const {list, run} = testRunner(tests); const button = html`