Write some tests.

composer.json

@@ -25,6 +25,7 @@
         "illuminate/http": "~8.0"
     },
     "require-dev": {
+        "mockery/mockery": "^1.4",
         "phpunit/phpunit": "^9.0",
         "squizlabs/php_codesniffer": "^3.5",
         "tightenco/tlint": "^5.0"

src/Solana.php

@@ -34,7 +34,7 @@ public function getTransaction(string $transactionSignature): array
         return $this->client->call('getTransaction', [$transactionSignature])['result'];
     }
 
-    public function __call($method, array $params = []): Response
+    public function __call($method, array $params = []): ?array
     {
         return $this->client->call($method, $params)->json();
     }

src/SolanaRpcClient.php

@@ -38,7 +38,7 @@ public function call(string $method, array $params = []): Response
         return $response;
     }
 
-    protected function buildRpc(string $method, array $params): array
+    public function buildRpc(string $method, array $params): array
     {
         return [
             'jsonrpc' => '2.0',

tests/SolanaRpcClientTest.php

@@ -3,24 +3,37 @@
 namespace Tighten\SolanaPhpSdk\Tests;
 
 use PHPUnit\Framework\TestCase;
+use Tighten\SolanaPhpSdk\SolanaRpcClient;
 
 class SolanaRpcClientTest extends TestCase
 {
     /** @test */
     public function it_generates_random_key()
     {
-        $this->markTestIncomplete();
+        $client = new SolanaRpcClient('abc.com');
+        $rpc1 = $client->buildRpc('doStuff', []);
+        $rpc2 = $client->buildRpc('doStuff', []);
+
+        $client = new SolanaRpcClient('abc.com');
+        $rpc3= $client->buildRpc('doStuff', []);
+        $rpc4 = $client->buildRpc('doStuff', []);
+
+        $this->assertEquals($rpc1['id'], $rpc2['id']);
+        $this->assertEquals($rpc3['id'], $rpc4['id']);
+        $this->assertNotEquals($rpc1['id'], $rpc4['id']);
     }
 
     /** @test */
     public function it_validates_response_id()
     {
+        // If we get back a response that doesn't have id set to this->randomKey, throw exception
         $this->markTestIncomplete();
     }
 
     /** @test */
     public function it_throws_exception_for_invalid_methods()
     {
+        // If we get an error: invalid method response back, throw the correct exception
         $this->markTestIncomplete();
     }
 }

tests/SolanaTest.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace Tighten\SolanaPhpSdk\Tests;
+
+use Illuminate\Http\Client\Response;
+use Mockery as M;
+use PHPUnit\Framework\TestCase;
+use Tighten\SolanaPhpSdk\Solana;
+use Tighten\SolanaPhpSdk\SolanaRpcClient;
+
+class SolanaTest extends TestCase
+{
+    /** @test */
+    public function it_passes_undefined_calls_through_magically()
+    {
+        $client = M::mock(SolanaRpcClient::class);
+        $client->shouldReceive('call')
+            ->with('abcdefg', [])
+            ->times(1)
+            ->andReturn($this->fakeResponse());
+
+        $solana = new Solana($client);
+        $solana->abcdefg();
+
+        M::close();
+
+        $this->assertTrue(true); // Keep PHPUnit from squawking; there must be a better way?
+    }
+
+    protected function fakeResponse(): Response
+    {
+        return new Response(new class
+        {
+            public function getBody()
+            {
+                return 'i am a body yay';
+            }
+        });
+    }
+}