src,test: fix config file parsing for flags defaulted to true · nodejs/node@ef89c2f

Original file line number	Diff line number	Diff line change
`@@ -55,6 +55,10 @@ ParseResult ConfigReader::ProcessOptionValue(`
`55`	`55`	`if (result) {`
`56`	`56`	`// If the value is true, we need to set the flag`
`57`	`57`	`output->push_back(option_name);`
	`58`	`+ } else {`
	`59`	`+// Ensure negation is made putting the "--no-" prefix`
	`60`	`+ output->push_back("--no-" +`
	`61`	`+ option_name.substr(2, option_name.size() - 2));`
`58`	`62`	`}`
`59`	`63`
`60`	`64`	`break;`

Original file line number	Diff line number	Diff line change
`@@ -60,6 +60,17 @@ test('should parse boolean flag', async () => {`
`60`	`60`	`strictEqual(result.code, 0);`
`61`	`61`	`});`
`62`	`62`
	`63`	`+test('should parse boolean flag defaulted to true', async () => {`
	`64`	`+const result = await spawnPromisified(process.execPath, [`
	`65`	`+'--experimental-config-file',`
	`66`	`+fixtures.path('rc/warnings-false.json'),`
	`67`	`+'-p', 'process.emitWarning("A warning")',`
	`68`	`+]);`
	`69`	`+strictEqual(result.stderr, '');`
	`70`	`+strictEqual(result.stdout, 'undefined\n');`
	`71`	`+strictEqual(result.code, 0);`
	`72`	`+});`
	`73`	`+`
`63`	`74`	`test('should throw an error when a flag is declared twice', async () => {`
`64`	`75`	`const result = await spawnPromisified(process.execPath, [`
`65`	`76`	`'--no-warnings',`