Add shortcut for optional nullable param, closes #5

Author: pinepain

src/Specs/Builder/ParameterSpecBuilder.php

@@ -35,6 +35,9 @@ class ParameterSpecBuilder implements ParameterSpecBuilderInterface
             \s*
         )?
         (?<name>[_a-z]\w*)
+        \s*
+        (?<nullable>\?)?
+        \s*
         (?:
             \s* = \s*
             (?<default>
@@ -86,13 +89,20 @@ public function build(string $definition): ParameterSpecInterface
         }
 
         if (preg_match($this->regexp, $definition, $matches)) {
+
+            $this->validateDefinition($definition, $matches);
+
             try {
-                if ($matches['rest'] ?? false) {
+                if ($this->hasRest($matches)) {
                     return $this->buildVariadicParameterSpec($matches);
                 }
 
-                if ($matches['default'] ?? false) {
-                    return $this->buildOptionalParameterSpec($matches);
+                if ($this->hasDefault($matches)) {
+                    return $this->buildOptionalParameterSpec($matches, $matches['default']);
+                }
+
+                if ($this->hasNullable($matches)) {
+                    return $this->buildOptionalParameterSpec($matches, null);
                 }
 
                 return $this->buildMandatoryParameterSpec($matches);
@@ -106,16 +116,14 @@ public function build(string $definition): ParameterSpecInterface
 
     protected function buildVariadicParameterSpec(array $matches): VariadicParameterSpec
     {
-        if (isset($matches['default']) && '' !== $matches['default']) {
-            throw new ParameterSpecBuilderException('Variadic parameter should have no default value');
-        }
-
         return new VariadicParameterSpec($matches['name'], $this->builder->build($matches['type']));
     }
 
-    protected function buildOptionalParameterSpec(array $matches): OptionalParameterSpec
+    protected function buildOptionalParameterSpec(array $matches, ?string $default): OptionalParameterSpec
     {
-        $default = $this->buildDefaultValue($matches['default']);
+        if (null !== $default) {
+            $default = $this->buildDefaultValue($matches['default']);
+        }
 
         return new OptionalParameterSpec($matches['name'], $this->builder->build($matches['type']), $default);
     }
@@ -166,6 +174,7 @@ protected function buildDefaultValue(string $definition)
             }
         }
 
+        // UNEXPECTED
         // Less likely we will ever get here because it should fail at a parsing step, but just in case
         throw new ParameterSpecBuilderException("Unknown default value format '{$definition}'");
     }
@@ -176,4 +185,34 @@ private function wrappedWith(string $definition, string $starts, $ends)
 
         return $starts == $definition[0] && $ends == $definition[-1];
     }
+
+    protected function validateDefinition(string $definition, array $matches): void
+    {
+        if ($this->hasNullable($matches) && $this->hasRest($matches)) {
+            throw new ParameterSpecBuilderException("Variadic parameter could not be nullable");
+        }
+
+        if ($this->hasNullable($matches) && $this->hasDefault($matches)) {
+            throw new ParameterSpecBuilderException("Nullable parameter could not have default value");
+        }
+
+        if ($this->hasRest($matches) && $this->hasDefault($matches)) {
+            throw new ParameterSpecBuilderException('Variadic parameter could have no default value');
+        }
+    }
+
+    private function hasNullable(array $matches): bool
+    {
+        return isset($matches['nullable']) && '' !== $matches['nullable'];
+    }
+
+    private function hasRest(array $matches): bool
+    {
+        return isset($matches['rest']) && '' !== $matches['rest'];
+    }
+
+    private function hasDefault(array $matches): bool
+    {
+        return isset($matches['default']) && '' !== $matches['default'];
+    }
 }

tests/Specs/Builder/FunctionSpecBuilderTest.php

@@ -117,7 +117,18 @@ public function testBuildSpecWithParams()
         $this->assertFalse($spec->needsExecutionContext());
         $this->assertContainsOnlyInstancesOf(ParameterSpecInterface::class, $spec->getParameters()->getParameters());
         $this->assertCount(3, $spec->getParameters()->getParameters());
+    }
+
+    public function testBuildSpecWithNullableParams()
+    {
+        $this->parameterSpecBuilderShouldBuildOn('one: param', 'two?: param');
+
+        $spec = $this->builder->build('(one: param, two?: param)');
 
+        $this->assertInstanceOf(FunctionSpecInterface::class, $spec);
+        $this->assertFalse($spec->needsExecutionContext());
+        $this->assertContainsOnlyInstancesOf(ParameterSpecInterface::class, $spec->getParameters()->getParameters());
+        $this->assertCount(2, $spec->getParameters()->getParameters());
     }
 
     // Test throws spec

tests/Specs/Builder/ParameterSpecBuilderTest.php

@@ -134,13 +134,44 @@ public function testBuildingVariadicParameter()
 
     /**
      * @expectedException \Pinepain\JsSandbox\Specs\Builder\Exceptions\ParameterSpecBuilderException
-     * @expectedExceptionMessage Variadic parameter should have no default value
+     * @expectedExceptionMessage Variadic parameter could have no default value
      */
     public function testBuildingVariadicParameterWithDefaultValueShouldThrowException()
     {
         $this->builder->build('...param = []: type');
     }
 
+    /**
+     * @expectedException \Pinepain\JsSandbox\Specs\Builder\Exceptions\ParameterSpecBuilderException
+     * @expectedExceptionMessage Variadic parameter could not be nullable
+     */
+    public function testBuildingVariadicParameterWithNullableShouldThrowException()
+    {
+        $this->builder->build('...param?: type');
+    }
+
+    /**
+     * @expectedException \Pinepain\JsSandbox\Specs\Builder\Exceptions\ParameterSpecBuilderException
+     * @expectedExceptionMessage Nullable parameter could not have default value
+     */
+    public function testBuildingNullableParameterWithDefaultValueShouldThrowException()
+    {
+        $this->builder->build('param? = "default": type');
+    }
+
+    public function testBuildingNullableParameter()
+    {
+        $this->extractorDefinitionShouldBuildOn('type');
+
+        $spec = $this->builder->build('param? : type');
+
+        $this->assertInstanceOf(OptionalParameterSpec::class, $spec);
+
+        $this->assertSame('param', $spec->getName());
+        $this->assertNull($spec->getDefaultValue());
+        $this->assertInstanceOf(ExtractorDefinitionInterface::class, $spec->getExtractorDefinition());
+    }
+
     /**
      * @expectedException \Pinepain\JsSandbox\Specs\Builder\Exceptions\ParameterSpecBuilderException
      * @expectedExceptionMessage Unable to parse definition because of extractor failure: ExtractorDefinitionBuilder exception for testing