From 42c4f74c732fa531c9493f7eacac9fae41da2a31 Mon Sep 17 00:00:00 2001
From: Kentaro Hayashi <kenhys@gmail.com>
Date: Mon, 24 Aug 2020 13:41:52 +0900
Subject: [PATCH] Windows: support check_is_installed_by_gem

Example:

  describe package("#{spec.name}") do
    it { should be_installed.by("gem").with_version(spec.version) }
  end

This commit fixes the following error:

  check_is_installed_by_gem is not implemented in Specinfra::Command::Windows::Base::Package
---
 .../powershell/support/find_installed_gem.ps1 | 20 +++++++++++++++++++
 lib/specinfra/command/windows/base/package.rb |  8 ++++++++
 2 files changed, 28 insertions(+)
 create mode 100644 lib/specinfra/backend/powershell/support/find_installed_gem.ps1

diff --git a/lib/specinfra/backend/powershell/support/find_installed_gem.ps1 b/lib/specinfra/backend/powershell/support/find_installed_gem.ps1
new file mode 100644
index 000000000..815a10252
--- /dev/null
+++ b/lib/specinfra/backend/powershell/support/find_installed_gem.ps1
@@ -0,0 +1,20 @@
+function FindInstalledGem
+{
+  param($gemName, $gemVersion)
+
+  $nameVer = $(Invoke-Expression "gem list --local" | Select-String "$gemName").Line
+  if ($nameVer.StartsWith($gemName)) {
+    if ($gemVersion) {
+      if ($nameVer.EndsWith("$gemVersion)")) {
+        $true
+      } else {
+        $false
+      }
+    } else {
+      $true
+    }
+  } else {
+    $false
+  }
+}
+
diff --git a/lib/specinfra/command/windows/base/package.rb b/lib/specinfra/command/windows/base/package.rb
index e52acd78f..0b953c041 100644
--- a/lib/specinfra/command/windows/base/package.rb
+++ b/lib/specinfra/command/windows/base/package.rb
@@ -7,5 +7,13 @@ def check_is_installed(package, version=nil)
         exec "(FindInstalledApplication -appName '#{package}' #{version_selection}) -eq $true"
       end
     end
+
+    def check_is_installed_by_gem(name, version=nil, gem_binary="gem")
+      version_selection = version.nil? ? "" : "-gemVersion '#{version}'"
+      Backend::PowerShell::Command.new do
+        using 'find_installed_gem.ps1'
+        exec "(FindInstalledGem -gemName '#{name}' #{version_selection}) -eq $true"
+      end
+    end
   end
 end