Handle malformed JSON (#26)

src/Exceptions/MalformedJsonException.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace Bauhaus\AssertPsrResponse\Exceptions;
+
+use InvalidArgumentException;
+use Throwable;
+
+class MalformedJsonException extends InvalidArgumentException
+{
+    public function __construct(string $malformedJson, Throwable $previousEx)
+    {
+        $message = "Malformed JSON provided:\n$malformedJson";
+        $code = 0;
+
+        parent::__construct($message, $code, $previousEx);
+    }
+}

src/PsrResponseAssertionException.php → src/Exceptions/PsrResponseAssertionException.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Bauhaus\AssertPsrResponse;
+namespace Bauhaus\AssertPsrResponse\Exceptions;
 
 use RuntimeException;
 

src/Matchers/JsonBody.php

@@ -2,27 +2,28 @@
 
 namespace Bauhaus\AssertPsrResponse\Matchers;
 
+use Bauhaus\AssertPsrResponse\Exceptions\MalformedJsonException;
 use Psr\Http\Message\ResponseInterface as PsrResponse;
 use Fefas\Jsoncoder\Json;
+use InvalidArgumentException;
 
-class JsonBody implements Matcher
+final class JsonBody implements Matcher
 {
     private const MISMATCH_MESSAGE =
         'Actual response json body \'%s\' is not equal to the expected \'%s\'';
 
-    private string $expected;
+    private Json $expected;
 
-    public function __construct(string $expected)
+    private function __construct(string $expected)
     {
-        $this->expected = $expected;
+        $this->expected = $this->handleJson($expected);
     }
 
     public function match(PsrResponse $psrResponse): bool
     {
-        $expected = Json::createFromString($this->expected);
-        $actual = Json::createFromString($this->extractBody($psrResponse));
+        $actual = $this->handleJson($this->extractBody($psrResponse));
 
-        return $expected->isEqualTo($actual);
+        return $this->expected->isEqualTo($actual);
     }
 
     public function mismatchMessage(PsrResponse $psrResponse): string
@@ -39,4 +40,13 @@ private function extractBody(PsrResponse $psrResponse): string
     {
         return (string) $psrResponse->getBody();
     }
+
+    private function handleJson(string $jsonString): Json
+    {
+        try {
+            return Json::createFromString($jsonString);
+        } catch (InvalidArgumentException $ex) {
+            throw new MalformedJsonException($jsonString, $ex);
+        }
+    }
 }

src/PsrResponseAssertion.php

@@ -2,6 +2,7 @@
 
 namespace Bauhaus\AssertPsrResponse;
 
+use Bauhaus\AssertPsrResponse\Exceptions\PsrResponseAssertionException;
 use Bauhaus\AssertPsrResponse\Matchers\Matcher;
 use Psr\Http\Message\ResponseInterface as PsrResponse;
 

tests/Matchers/JsonBodyTest.php

@@ -2,6 +2,7 @@
 
 namespace Bauhaus\AssertPsrResponse\Matchers;
 
+use Bauhaus\AssertPsrResponse\Exceptions\MalformedJsonException;
 use Bauhaus\AssertPsrResponse\TestCase;
 
 class JsonBodyTest extends TestCase
@@ -45,4 +46,27 @@ public function returnMismatchMessageAccordingToExpectedAndActualValues(): void
         $expected = 'Actual response json body \'[1,2,3]\' is not equal to the expected \'[1,2]\'';
         $this->assertEquals($expected, $mismatchMessage);
     }
+
+    /**
+     * @test
+     */
+    public function throwExceptionIfAMalformedJsonIsProvidedAsExpectedValue(): void
+    {
+        $this->expectException(MalformedJsonException::class);
+
+        JsonBody::equalTo('[1,2');
+    }
+
+    /**
+     * @test
+     */
+    public function throwExceptionIfResponseToAssertHasAMalformedJson(): void
+    {
+        $jsonBodyMatcher = JsonBody::equalTo('[1,2]');
+        $responseToAssert = $this->responseWithJsonBody('[1,2,3');
+
+        $this->expectException(MalformedJsonException::class);
+
+        $jsonBodyMatcher->match($responseToAssert);
+    }
 }

tests/TestCase.php

@@ -2,6 +2,7 @@
 
 namespace Bauhaus\AssertPsrResponse;
 
+use Bauhaus\AssertPsrResponse\Exceptions\PsrResponseAssertionException;
 use PHPUnit\Framework\TestCase as PhpUnitTestCase;
 use Psr\Http\Message\ResponseInterface as Response;
 use Psr\Http\Message\StreamInterface as Stream;