Test coverage for DownloadStrategyDetector

While at it, make it use class methods instead; no reason to instantiate
an object for this.

Eventually there should be some functional tests for the individual
strategies as well.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

3 files changed, 32 insertions, 16 deletions

diff --git a/Library/Homebrew/download_strategy.rb b/Library/Homebrew/download_strategy.rb
index 6d16deb5f..f0347d762 100644
--- a/Library/Homebrew/download_strategy.rb
+++ b/Library/Homebrew/download_strategy.rb
@@ -586,23 +586,20 @@ class FossilDownloadStrategy < AbstractDownloadStrategy
 end
 
 class DownloadStrategyDetector
-  def initialize url, strategy=nil
-    @url = url
-    @strategy = strategy
-  end
-
-  def detect
-    if @strategy.is_a? Class and @strategy.ancestors.include? AbstractDownloadStrategy
-      @strategy
-    elsif @strategy.is_a? Symbol then detect_from_symbol
-    else detect_from_url
+  def self.detect(url, strategy=nil)
+    if strategy.is_a? Class and strategy.ancestors.include? AbstractDownloadStrategy
+      strategy
+    elsif strategy.is_a? Symbol
+      detect_from_symbol(strategy)
+    else
+      detect_from_url(url)
     end
   end
 
   private
 
-  def detect_from_url
-    case @url
+  def self.detect_from_url(url)
+    case url
       # We use a special URL pattern for cvs
     when %r[^cvs://] then CVSDownloadStrategy
       # Standard URLs
@@ -628,8 +625,8 @@ class DownloadStrategyDetector
     end
   end
 
-  def detect_from_symbol
-    case @strategy
+  def self.detect_from_symbol(symbol)
+    case symbol
     when :bzr then BazaarDownloadStrategy
     when :curl then CurlDownloadStrategy
     when :cvs then CVSDownloadStrategy
@@ -639,7 +636,7 @@ class DownloadStrategyDetector
     when :post then CurlPostDownloadStrategy
     when :svn then SubversionDownloadStrategy
     else
-      raise "Unknown download strategy #{@strategy} was requested."
+      raise "Unknown download strategy #{strategy} was requested."
     end
   end
 end
diff --git a/Library/Homebrew/formula_support.rb b/Library/Homebrew/formula_support.rb
index 1bf3fbc58..f72358d4d 100644
--- a/Library/Homebrew/formula_support.rb
+++ b/Library/Homebrew/formula_support.rb
@@ -12,7 +12,7 @@ class SoftwareSpec
   end
 
   def download_strategy
-    @download_strategy ||= DownloadStrategyDetector.new(@url, @using).detect
+    @download_strategy ||= DownloadStrategyDetector.detect(@url, @using)
   end
 
   def verify_download_integrity fn
diff --git a/Library/Homebrew/test/test_download_strategies.rb b/Library/Homebrew/test/test_download_strategies.rb
new file mode 100644
index 000000000..13392272b
--- /dev/null
+++ b/Library/Homebrew/test/test_download_strategies.rb
@@ -0,0 +1,19 @@
+require 'testing_env'
+require 'download_strategy'
+require 'bottles' # XXX: hoist these regexps into constants in Pathname?
+
+class DownloadStrategyDetectorTests < Test::Unit::TestCase
+  def setup
+    @d = DownloadStrategyDetector.new
+  end
+
+  def test_detect_git_download_startegy
+    @d = DownloadStrategyDetector.detect("git://foo.com/bar.git")
+    assert_equal GitDownloadStrategy, @d
+  end
+
+  def test_default_to_curl_strategy
+    @d = DownloadStrategyDetector.detect(Object.new)
+    assert_equal CurlDownloadStrategy, @d
+  end
+end