Getting PHPUNit code coverage of simple '} else {' line - php

Question

I can't get PHPUnit's Code Coverage tool to mark this else statement as covered even though it must be or the following line could not be covered. Elsewhere in the same class another line that contains only } else { is correctly marked as covered.
if (is_string($externalId) && $externalId != '') {
$sitesIds[] = $externalId;
} else if ($regionName != null && $regionName != '') {
$sitesIds = $this->sitesService->getSites($regionName);
if (!is_array($sitesIds) || count($sitesIds) == 0) {
throw new \Exception(self::NO_MATCHING_REGION, '404');
}
} else {
throw new \Exception(self::BAD_REQUEST.'. Should specify station or region', '400');
}

Answer 1

Since else doesn't actually do anything (it can be considered just a label) it won't get covered.
Your problem is that you don't have a test where (is_string($externalId) && $externalId != '') is false, ($regionName != null && $regionName != '') is true and (!is_array($sitesIds) || count($sitesIds) == 0) is false. (You might want to be more specific by using not exactly equal to !== instead of not equal to !=: ($externalId !== '') & ($regionName !== null && $regionName !== ''))
If you can get $sitesIds = $this->sitesService->getSites($regionName); to return an array with at least one element, your red line will be covered and turn green.
The red line is telling you that the closing brace } before the else is technically reachable, but you have no tests that cover it.

Answer 2

With slightly modified source:
class A
{
const NO_MATCHING_REGION = 1;
const BAD_REQUEST = 2;
private $sitesService = ['a' => ['AA'], 'b'=>12];
public function a($externalId, $regionName)
{
$sitesIds = [];
if (is_string($externalId) && $externalId != '') {
$sitesIds[] = $externalId;
} else {
if ($regionName != null && $regionName != '') {
$sitesIds = $this->sitesService[$regionName];
if (!is_array($sitesIds) || count($sitesIds) == 0) {
throw new \Exception(self::NO_MATCHING_REGION, '404');
}
} else {
throw new \Exception(self::BAD_REQUEST.'. Should specify station or region', '400');
}
}
return $sitesIds;
}
}
The test
class ATest extends \PHPUnit_Framework_TestCase
{
/**
* #dataProvider data
*/
public function testOk($id, $reg, $res)
{
$a = new A;
$r = $a->a($id, $reg);
$this->assertEquals($res, $r);
}
public function data()
{
return [
['a', 1, ['a']],
[1,'a', ['AA']]
];
}
/**
* #dataProvider error
* #expectedException \Exception
*/
public function testNotOK($id, $reg)
{
$a = new A;
$a->a($id, $reg);
}
public function error()
{
return [
[1,'b'],
[1,null]
];
}
}
Covers the else line:
PHP 5.6.15-1+deb.sury.org~trusty+1
PHPUnit 4.8.21