diff --git a/.travis.yml b/.travis.yml
index d29ba72..7da156c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,6 +6,7 @@ php:
   - '7.0'
   - '7.1'
   - '7.2'
+  - '7.3'
   - 'nightly'
 
 matrix:
diff --git a/composer.json b/composer.json
index 23b4873..9d81168 100644
--- a/composer.json
+++ b/composer.json
@@ -8,6 +8,9 @@
     "psr-4": {"ExceptionalJSON\\": "src/"},
     "files": ["src/functions.php"]
   },
+  "autoload-dev": {
+    "psr-4": {"ExceptionalJSON\\Tests\\": "tests/"}
+  },
   "require": {
     "php": ">=7.0"
   },
diff --git a/phpunit.xml b/phpunit.xml
index d425b8a..f9d9b93 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -3,6 +3,7 @@
 <!-- https://phpunit.de/manual/5.3/en/appendixes.configuration.html -->
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/6.0/phpunit.xsd"
+         bootstrap="./vendor/autoload.php"
          colors="true"
 >
     <testsuites>
diff --git a/tests/DecodeTest.php b/tests/DecodeTest.php
index b139fa9..fd708a8 100644
--- a/tests/DecodeTest.php
+++ b/tests/DecodeTest.php
@@ -1,6 +1,11 @@
 <?php declare(strict_types=1);
 
-final class DecodeTest extends \PHPUnit\Framework\TestCase
+namespace ExceptionalJSON\Tests;
+
+use ExceptionalJSON\DecodeErrorException;
+use PHPUnit\Framework\TestCase;
+
+final class DecodeTest extends TestCase
 {
     const VALID_ENCODED = '{"string":"foo bar baz","array":[1,2,3],"bigint":12345678901234567890}';
     const DECODED = ["string" => "foo bar baz", "array" => [1,2,3], "bigint" => 12345678901234567890];
@@ -58,8 +63,9 @@ public function testDecodeValidJsonInvalidDepth()
     {
         try {
             \ExceptionalJSON\decode(self::VALID_ENCODED, false, 2);
-        } catch (\ExceptionalJSON\DecodeErrorException $e) {
+        } catch (DecodeErrorException $e) {
             $this->assertSame(\JSON_ERROR_DEPTH, $e->getCode());
+            $this->assertSame(self::VALID_ENCODED, $e->getJSON());
         }
     }
 
@@ -67,8 +73,9 @@ public function testDecodeInvalidJsonStateMismatch()
     {
         try {
             \ExceptionalJSON\decode('{"foo":"bar"]');
-        } catch (\ExceptionalJSON\DecodeErrorException $e) {
+        } catch (DecodeErrorException $e) {
             $this->assertSame(\JSON_ERROR_STATE_MISMATCH, $e->getCode());
+            $this->assertSame('{"foo":"bar"]', $e->getJSON());
         }
     }
 
@@ -76,8 +83,9 @@ public function testDecodeInvalidJsonControlChar()
     {
         try {
             \ExceptionalJSON\decode('{"foo"' . "\x03" . ':"bar"}');
-        } catch (\ExceptionalJSON\DecodeErrorException $e) {
+        } catch (DecodeErrorException $e) {
             $this->assertSame(\JSON_ERROR_CTRL_CHAR, $e->getCode());
+            $this->assertSame('{"foo"' . "\x03" . ':"bar"}', $e->getJSON());
         }
     }
 
@@ -85,8 +93,9 @@ public function testDecodeInvalidJsonSyntax()
     {
         try {
             \ExceptionalJSON\decode('{"foo" => "bar"}');
-        } catch (\ExceptionalJSON\DecodeErrorException $e) {
+        } catch (DecodeErrorException $e) {
             $this->assertSame(\JSON_ERROR_SYNTAX, $e->getCode());
+            $this->assertSame('{"foo" => "bar"}', $e->getJSON());
         }
     }
 
@@ -94,8 +103,9 @@ public function testDecodeInvalidUtf8()
     {
         try {
             \ExceptionalJSON\decode('{"foo' . "\x80\x80" . '":"bar"}');
-        } catch (\ExceptionalJSON\DecodeErrorException $e) {
+        } catch (DecodeErrorException $e) {
             $this->assertSame(\JSON_ERROR_UTF8, $e->getCode());
+            $this->assertSame('{"foo' . "\x80\x80" . '":"bar"}', $e->getJSON());
         }
     }
 
@@ -103,8 +113,9 @@ public function testDecodeInvalidPropertyName()
     {
         try {
             \ExceptionalJSON\decode('{"\u0000foo":"bar"}');
-        } catch (\ExceptionalJSON\DecodeErrorException $e) {
+        } catch (DecodeErrorException $e) {
             $this->assertSame(\JSON_ERROR_INVALID_PROPERTY_NAME, $e->getCode());
+            $this->assertSame('{"\u0000foo":"bar"}', $e->getJSON());
         }
     }
 }
diff --git a/tests/EncodeTest.php b/tests/EncodeTest.php
new file mode 100644
index 0000000..096167e
--- /dev/null
+++ b/tests/EncodeTest.php
@@ -0,0 +1,39 @@
+<?php declare(strict_types=1);
+
+namespace ExceptionalJSON\Tests;
+
+use ExceptionalJSON\EncodeErrorException;
+use PHPUnit\Framework\TestCase;
+
+final class EncodeTest extends TestCase
+{
+    const VALID_ENCODED = '{"string":"foo bar baz","array":[1,2,3],"bigint":"12345678901234567890"}';
+    const ASSOC_ARRAY = ["string" => "foo bar baz", "array" => [1,2,3], "bigint" => "12345678901234567890"];
+    const BIGINT_AS_STRING = "12345678901234567890";
+
+    public function testEncodeAssocArray()
+    {
+        $this->assertSame(
+            self::VALID_ENCODED,
+            \ExceptionalJSON\encode(self::ASSOC_ARRAY)
+        );
+    }
+
+    public function testEncodeBigIntegerString()
+    {
+        $this->assertSame(
+            '"' . self::BIGINT_AS_STRING . '"',
+            \ExceptionalJSON\encode(self::BIGINT_AS_STRING)
+        );
+    }
+
+    public function testEncodeNonUtf8String()
+    {
+        try {
+            \ExceptionalJSON\encode("\xB1\x31");
+        } catch (EncodeErrorException $e) {
+            $this->assertSame(5, $e->getCode());
+            $this->assertSame("\xB1\x31", $e->getValue());
+        }
+    }
+}