From f7bebdd8f8ef17a5d3caca717f442cf4206a10cd Mon Sep 17 00:00:00 2001
From: Damian Mooyman <damian@silverstripe.com>
Date: Mon, 7 Aug 2017 10:15:16 +1200
Subject: [PATCH] BUG Fix install issue with IIS Fixes #7218

---
 src/Dev/Install/InstallRequirements.php       | 19 +++----
 .../Dev/Install/InstallRequirementsTest.php   | 54 +++++++++++++++++++
 2 files changed, 64 insertions(+), 9 deletions(-)
 create mode 100644 tests/php/Dev/Install/InstallRequirementsTest.php

diff --git a/src/Dev/Install/InstallRequirements.php b/src/Dev/Install/InstallRequirements.php
index 889506338..1cdc46ee7 100644
--- a/src/Dev/Install/InstallRequirements.php
+++ b/src/Dev/Install/InstallRequirements.php
@@ -142,24 +142,25 @@ class InstallRequirements
      */
     public function isIIS($fromVersion = 7)
     {
-        if (strpos($this->findWebserver(), 'IIS/') === false) {
-            return false;
+        $webserver = $this->findWebserver();
+        if (preg_match('#.*IIS/(?<version>[.\\d]+)$#', $webserver, $matches)) {
+            return version_compare($matches['version'], $fromVersion, '>=');
         }
-        return substr(strstr($this->findWebserver(), '/'), -3, 1) >= $fromVersion;
+        return false;
     }
 
+    /**
+     * @return bool
+     */
     public function isApache()
     {
-        if (strpos($this->findWebserver(), 'Apache') !== false) {
-            return true;
-        } else {
-            return false;
-        }
+        return strpos($this->findWebserver(), 'Apache') !== false;
     }
 
     /**
      * Find the webserver software running on the PHP host.
-     * @return string|boolean Server software or boolean FALSE
+     *
+     * @return string|false Server software or boolean FALSE
      */
     public function findWebserver()
     {
diff --git a/tests/php/Dev/Install/InstallRequirementsTest.php b/tests/php/Dev/Install/InstallRequirementsTest.php
new file mode 100644
index 000000000..57c66db02
--- /dev/null
+++ b/tests/php/Dev/Install/InstallRequirementsTest.php
@@ -0,0 +1,54 @@
+<?php
+
+namespace SilverStripe\Dev\Tests\Install;
+
+use SilverStripe\Dev\Install\InstallRequirements;
+use SilverStripe\Dev\SapphireTest;
+
+class InstallRequirementsTest extends SapphireTest
+{
+    public function testIIS()
+    {
+        $requirements = new InstallRequirements();
+        $_SERVER['SERVER_SIGNATURE'] = 'Microsoft-IIS/10.0';
+
+        // Test server
+        $this->assertEquals('Microsoft-IIS/10.0', $requirements->findWebserver());
+
+        // True conditions
+        $this->assertTrue($requirements->isIIS());
+        $this->assertTrue($requirements->isIIS(10));
+        $this->assertTrue($requirements->isIIS('10.0'));
+        $this->assertTrue($requirements->isIIS(9));
+
+        // Negative - Based on number
+        $this->assertFalse($requirements->isIIS(11));
+        $_SERVER['SERVER_SIGNATURE'] = 'Microsoft-IIS/6.0';
+        $this->assertFalse($requirements->isIIS());
+        $_SERVER['SERVER_SIGNATURE'] = 'Microsoft-IIS/6.5';
+        $this->assertFalse($requirements->isIIS());
+
+        // Negative - Based on string
+        $_SERVER['SERVER_SOFTWARE'] = 'lighttpd/1.4.33';
+        $this->assertFalse($requirements->isIIS());
+        $_SERVER['SERVER_SOFTWARE'] = 'Apache/2.4.25 (Unix) PHP/5.6.30 LibreSSL/2.2.7';
+        $this->assertFalse($requirements->isIIS());
+    }
+
+    public function testApache()
+    {
+        $requirements = new InstallRequirements();
+        $_SERVER['SERVER_SIGNATURE'] = '';
+        $_SERVER['SERVER_SOFTWARE'] = 'Apache/2.4.25 (Unix) PHP/5.6.30 LibreSSL/2.2.7';
+
+        // Test server
+        $this->assertEquals('Apache/2.4.25 (Unix) PHP/5.6.30 LibreSSL/2.2.7', $requirements->findWebserver());
+
+        // True conditions
+        $this->assertTrue($requirements->isApache());
+
+        // False conditions
+        $_SERVER['SERVER_SOFTWARE'] = 'lighttpd/1.4.33';
+        $this->assertFalse($requirements->isApache());
+    }
+}