Issue #6: locator builder supports export to string

Author: remorhaz

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+### Added
+- Issue #6: locator builder supports export to string.
+
 ## [0.6.4] - 2019-11-20
 ### Added
 - Issue #5: `ResultInterface::get()` method added.

src/Locator/LocatorBuilder.php

@@ -3,6 +3,10 @@
 
 namespace Remorhaz\JSON\Pointer\Locator;
 
+use function array_map;
+use function implode;
+use function str_replace;
+
 final class LocatorBuilder implements LocatorBuilderInterface
 {
 
@@ -42,4 +46,26 @@ public function getLocator(): LocatorInterface
 
         return $this->locator;
     }
+
+    public function export(): string
+    {
+        $references = $this
+            ->getLocator()
+            ->references();
+
+        if (empty($references)) {
+            return '';
+        }
+
+        return '/' . implode('/', array_map([$this, 'escapeReference'], $references));
+    }
+
+    private function escapeReference(ListedReferenceInterface $reference): string
+    {
+        $text = $reference
+            ->getReference()
+            ->getPropertyName();
+
+        return str_replace(['~', '/'], ['~0', '~1'], $text);
+    }
 }

src/Locator/LocatorBuilderInterface.php

@@ -9,4 +9,6 @@ interface LocatorBuilderInterface
     public function addReference(string $text): void;
 
     public function getLocator(): LocatorInterface;
+
+    public function export(): string;
 }

tests/Locator/LocatorBuilderTest.php

@@ -5,6 +5,7 @@
 
 use PHPUnit\Framework\TestCase;
 use Remorhaz\JSON\Pointer\Locator\ListedReferenceInterface;
+use Remorhaz\JSON\Pointer\Locator\ReferenceFactory;
 use Remorhaz\JSON\Pointer\Locator\ReferenceFactoryInterface;
 use Remorhaz\JSON\Pointer\Locator\ReferenceInterface;
 use Remorhaz\JSON\Pointer\Locator\Exception\LocatorAlreadyBuiltException;
@@ -44,6 +45,14 @@ public function testAddReference_GetLocatorCalled_ThrowsException(): void
         $builder->addReference('a');
     }
 
+    public function testAddReference_ExportCalled_ThrowsException(): void
+    {
+        $builder = new LocatorBuilder($this->createMock(ReferenceFactoryInterface::class));
+        $builder->export();
+        $this->expectException(LocatorAlreadyBuiltException::class);
+        $builder->addReference('a');
+    }
+
     public function testAddReference_ConstructedWithReferenceFactory_PassesTextToSameInstance(): void
     {
         $referenceFactory = $this->createMock(ReferenceFactoryInterface::class);
@@ -80,4 +89,41 @@ function (ListedReferenceInterface $listedReference): ReferenceInterface {
         );
         self::assertSame([$firstReference, $secondReference], $actualValue);
     }
+
+    public function testExport_NoReferencesAdded_ReturnsEmptyPointer(): void
+    {
+        $referenceFactory = $this->createMock(ReferenceFactoryInterface::class);
+        $builder = new LocatorBuilder($referenceFactory);
+        self::assertSame('', $builder->export());
+    }
+
+    /**
+     * @param string $text
+     * @param string $expectedValue
+     * @dataProvider providerExportSingleReference
+     */
+    public function testExport_SingleReferenceAdded_ReturnsMatchingPointer(string $text, string $expectedValue): void
+    {
+        $builder = new LocatorBuilder(new ReferenceFactory);
+        $builder->addReference($text);
+        self::assertSame($expectedValue, $builder->export());
+    }
+    public function providerExportSingleReference(): array
+    {
+        return [
+            'ASCII string' => ['a', '/a'],
+            'Tilde' => ['~', '/~0'],
+            'Slash' => ['/', '/~1'],
+            'Tilde after slash' => ['/~', '/~1~0'],
+            'Slash after tilde' => ['~/', '/~0~1'],
+        ];
+    }
+
+    public function testExport_TwoReferencesAdded_ReturnsMatchingPointer(): void
+    {
+        $builder = new LocatorBuilder(new ReferenceFactory);
+        $builder->addReference('a');
+        $builder->addReference('b');
+        self::assertSame('/a/b', $builder->export());
+    }
 }