isValid debería ser una función.
testString: 'assert(typeof isValid=="function","isValid should be a function.");'
- text: 'isValid(""+tests[0]+"") debe devolver un valor booleano.'
testString: 'assert(typeof isValid(tests[0])=="boolean","isValid(""+tests[0]+"") should return a boolean.");'
- text: 'isValid(""+tests[0]+"") debe devolver true .'
testString: 'assert.equal(isValid(tests[0]),true,"isValid(""+tests[0]+"") should return true.");'
- text: 'isValid(""+tests[1]+"") debe devolver false .'
testString: 'assert.equal(isValid(tests[1]),false,"isValid(""+tests[1]+"") should return false.");'
- text: 'isValid(""+tests[2]+"") debe devolver false .'
testString: 'assert.equal(isValid(tests[2]),false,"isValid(""+tests[2]+"") should return false.");'
- text: 'isValid(""+tests[3]+"") debe devolver false .'
testString: 'assert.equal(isValid(tests[3]),false,"isValid(""+tests[3]+"") should return false.");'
- text: 'isValid(""+tests[4]+"") debe devolver true .'
testString: 'assert.equal(isValid(tests[4]),true,"isValid(""+tests[4]+"") should return true.");'
```