Add config class to handle git config

readme.md

@@ -220,6 +220,20 @@ $repo->setRemoteUrl('remote-name', 'new-repository-url');
 $repo->setRemoteUrl('upstream', 'https://github.com/czproject/git-php.git');
 ```
 
+Config
+------
+
+``` php
+// get config object of repo
+$config = $repo->getGitConfig();
+
+// set a option
+$config->set('option.name', 'value', ['--options']);
+
+// get a value for option (returns NULL if not set)
+$config->set('option.name', ['--options']);
+```
+
 **Troubleshooting - How to provide username and password for commands**
 
 1) use SSH instead of HTTPS - https://stackoverflow.com/a/8588786

src/GitConfig.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace CzProject\GitPhp;
+
+class GitConfig
+{
+    /** @var GitRepository */
+    protected $repository;
+
+    /** @var IRunner */
+    protected $runner;
+
+
+    public function __construct(GitRepository $repository, IRunner $runner = NULL)
+    {
+        $this->repository = $repository;
+        $this->runner = $runner !== NULL ? $runner : new Runners\CliRunner;
+    }
+
+
+    /**
+     * @param  string $name
+     * @param  string $value
+     * @param  array|string $params
+     * @throws GitException
+     * @return static
+     */
+    public function set($name, $value, $params = [])
+    {
+        $this->run('config', $params, (string) $name, (string) $value);
+        return $this;
+    }
+
+
+    /**
+     * @param  string $name
+     * @param  array|string $params
+     * @return string|null NULL if the option is not set
+     * @throws GitException
+     */
+    public function get($name, $params = [])
+    {
+        try {
+            $result = $this->run('config', $params, (string)$name);
+            return rtrim($result->getOutputAsString());
+        } catch (GitException $e) {
+            if (false === $e->getRunnerResult()->hasOutput()
+                && false === $e->getRunnerResult()->hasErrorOutput()
+            ) {
+                return NULL;
+            }
+            throw $e;
+        }
+    }
+
+
+    /**
+     * Runs command and returns result.
+     * @param  mixed ...$args
+     * @return RunnerResult
+     * @throws GitException
+     */
+    private function run(...$args)
+    {
+        $result = $this->runner->run($this->repository->getRepositoryPath(), $args);
+
+        if (!$result->isOk()) {
+            throw new GitException("Command '{$result->getCommand()}' failed (exit-code {$result->getExitCode()}).", $result->getExitCode(), NULL, $result);
+        }
+
+        return $result;
+    }
+}

src/GitRepository.php

@@ -5,7 +5,7 @@
 
 	class GitRepository
 	{
-		/** @var  string */
+		/** @var string */
 		protected $repository;
 
 		/** @var IRunner */
@@ -42,7 +42,17 @@ public function getRepositoryPath()
 		}
 
 
-		/**
+        /**
+         * @return GitConfig
+         */
+        public function getGitConfig()
+        {
+            return new GitConfig($this, $this->runner);
+        }
+
+
+
+        /**
 		 * Creates a tag.
 		 * `git tag <name>`
 		 * @param  string $name

tests/GitPhp/GitConfig.phpt

@@ -0,0 +1,27 @@
+<?php
+
+use CzProject\GitPhp\GitConfig;
+use Tester\Assert;
+use CzProject\GitPhp\Git;
+use CzProject\GitPhp\Tests\AssertRunner;
+
+require __DIR__ . '/bootstrap.php';
+
+$runner = new AssertRunner(__DIR__);
+$git = new Git($runner);
+
+$repo = $git->open(__DIR__);
+$config = $repo->getGitConfig();
+Assert::same(GitConfig::class, get_class($config));
+
+$runner->assert(['config', 'user.name', 'tester']);
+$config->set('user.name', 'tester');
+
+$runner->assert(['config', '--global', 'user.name', 'tester']);
+$config->set('user.name', 'tester', '--global');
+
+$runner->assert(['config', 'user.name']);
+$config->get('user.name');
+
+$runner->assert(['config', '--local', 'user.name']);
+$config->get('user.name', ['--local']);