Enhancement: Show output when no tests could be detected with a duration exceeding the maximum duration

Author: localheinz

CHANGELOG.md

@@ -8,6 +8,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 For a full diff see [`2.20.0...main`][2.20.0...main].
 
+### Changed
+
+- Started showing output when no tests could be detected with a duration exceeding the maximum duration ([#714]), by [@localheinz]
+
 ## [`2.20.0`][2.20.0]
 
 For a full diff see [`2.19.1...2.20.0`][2.19.1...2.20.0].
@@ -423,6 +427,7 @@ For a full diff see [`7afa59c...1.0.0`][7afa59c...1.0.0].
 [#651]: https://github.com/ergebnis/phpunit-slow-test-detector/pull/651
 [#664]: https://github.com/ergebnis/phpunit-slow-test-detector/pull/664
 [#704]: https://github.com/ergebnis/phpunit-slow-test-detector/pull/704
+[#714]: https://github.com/ergebnis/phpunit-slow-test-detector/pull/714
 
 [@dantleech]: https://github.com/dantleech
 [@HypeMC]: https://github.com/HypeMC

src/Reporter/DefaultReporter.php

@@ -43,10 +43,6 @@ public function __construct(
 
     public function report(SlowTestList $slowTestList): string
     {
-        if ($slowTestList->isEmpty()) {
-            return '';
-        }
-
         return \implode("\n", \iterator_to_array($this->lines($slowTestList)));
     }
 
@@ -57,6 +53,12 @@ private function lines(SlowTestList $slowTestList): \Generator
     {
         $slowTestCount = $slowTestList->count();
 
+        if ($slowTestCount->equals(Count::fromInt(0))) {
+            yield 'Could not detect any tests where the duration exceeded the maximum duration.';
+
+            return;
+        }
+
         if ($slowTestCount->equals(Count::fromInt(1))) {
             yield 'Detected 1 test where the duration exceeded the maximum duration.';
         } else {

test/Unit/Reporter/DefaultReporterTest.php

@@ -57,7 +57,7 @@ public function testReportReturnsEmptyStringWhenSlowTestListIsEmpty()
 
         $report = $reporter->report($slowTestList);
 
-        self::assertSame('', $report);
+        self::assertSame('Could not detect any tests where the duration exceeded the maximum duration.', $report);
     }
 
     /**