Handle more input values

CHANGELOG.md

@@ -2,7 +2,9 @@
 
 ## Unreleased
 
-* PHP 7.3 is now the minimum required version
+* PHP 7.3 is now the minimum required version.
+* `0`, `null`, `false`, `true` are now supported values as in that they result in `Duration::none()` (`PT0S`).
+* An `InvalidDuration` error will be thrown if a value is given without a unit or if the given value cannot be parsed. 
 * `toIntervalSpec()` did more than it needed to do. Instead of formatting the current value the spec itself is now returned.
 
 ## 3.0.1 - 2019-01-28

src/Duration.php

@@ -7,6 +7,7 @@
 use DateInterval;
 use DateTimeImmutable;
 use Gamez\Duration\Exception\InvalidDuration;
+use Throwable;
 
 final class Duration implements \JsonSerializable
 {
@@ -28,7 +29,19 @@ public static function make($value): self
             return new self($value);
         }
 
-        $stringValue = (string) $value;
+        if (in_array($value, [0, null, false, true], true)) {
+            return self::none();
+        }
+
+        $stringValue = trim((string) $value);
+
+        if ($value === '') {
+            return self::none();
+        }
+
+        if (ctype_digit($stringValue)) {
+            throw InvalidDuration::because('A duration needs a unit');
+        }
 
         if (preg_match('/^(\d+):(\d+)$/', $stringValue)) {
             [$minutes, $seconds] = array_map('intval', explode(':', $stringValue));
@@ -46,7 +59,11 @@ public static function make($value): self
             return new self(new DateInterval($stringValue));
         }
 
-        return new self(DateInterval::createFromDateString($stringValue));
+        try {
+            return new self(DateInterval::createFromDateString($stringValue));
+        } catch (Throwable $e) {
+            throw InvalidDuration::because('Unable to parse value: '.$e->getMessage());
+        }
     }
 
     public static function none(): self

tests/DurationTest.php

@@ -32,6 +32,9 @@ public function it_parses_a_value($value, $expectedSpec)
     public function validValues()
     {
         return [
+            'nothing (null)' => [null, 'PT0S'],
+            'nothing (false)' => [false, 'PT0S'],
+            'nothing (true)' => [true, 'PT0S'],
             'nothing ("")' => ['', 'PT0S'],
             'textual ("13 minutes 37 seconds")' => ['13 minutes 37 seconds', 'PT13M37S'],
             'minutes:seconds ("01:23")' => ['01:23', 'PT1M23S'],
@@ -43,6 +46,20 @@ public function validValues()
         ];
     }
 
+    /** @test */
+    public function it_needs_a_unit()
+    {
+        $this->expectException(InvalidDuration::class);
+        Duration::make(60);
+    }
+
+    /** @test */
+    public function it_needs_a_parseable_value()
+    {
+        $this->expectException(InvalidDuration::class);
+        Duration::make('xxx');
+    }
+
     /** @test */
     public function it_optimizes_the_date_interval_spec()
     {