Merge pull request #3561 from CocoaPods/mr-fix-incomplete-cache

[Cache] Recognize incomplete cache for released pods

CHANGELOG.md

@@ -12,6 +12,11 @@ To install release candidates run `[sudo] gem install cocoapods --pre`
   [Boris Bügling](https://github.com/neonichu)
   [#3600](https://github.com/CocoaPods/CocoaPods/issues/3600)
 
+* Recognizes incomplete cache when the original download of a pod was
+  interrupted.  
+  [Marius Rackwitz](https://github.com/mrackwitz)
+  [#3561](https://github.com/CocoaPods/CocoaPods/issues/3561)
+
 * Allow opting out of pod source locking, meaning `pod try` yields editable
   projects.  
   [Samuel Giddins](https://github.com/segiddins)

lib/cocoapods/downloader/cache.rb

@@ -76,9 +76,10 @@ module Pod
       #         was found in the download cache.
       #
       def cached_pod(request)
+        cached_spec = cached_spec(request)
         path = path_for_pod(request)
-        spec = request.spec || cached_spec(request)
-        return unless spec && path.directory?
+        return unless cached_spec && path.directory?
+        spec = request.spec || cached_spec
         Response.new(path, spec, request.params)
       end
 
@@ -91,6 +92,8 @@ module Pod
       def cached_spec(request)
         path = path_for_spec(request)
         path.file? && Specification.from_file(path)
+      rescue JSON::ParserError
+        nil
       end
 
       # @param  [Request] request

spec/unit/downloader/cache_spec.rb

@@ -74,6 +74,53 @@ module Pod
       end
     end
 
+    describe 'when the cache is incomplete' do
+      shared 'it falls back to download the pod' do
+        describe 'when downloading a released pod' do
+          it 'does download the source' do
+            Downloader::Git.any_instance.expects(:download).never
+            @cache.expects(:uncached_pod).once
+            @cache.download_pod(@request)
+          end
+        end
+
+        describe 'when downloading an unreleased pod' do
+          it 'does download the source' do
+            Downloader::Git.any_instance.expects(:download).never
+            @cache.expects(:uncached_pod).once
+            @cache.download_pod(@unreleased_request)
+          end
+        end
+      end
+
+      before do
+        [@request, @unreleased_request].each do |request|
+          path_for_pod = @cache.send(:path_for_pod, request)
+          path_for_pod.mkpath
+          Dir.chdir(path_for_pod) do
+            FileUtils.mkdir_p 'Classes'
+            File.open('Classes/a.m', 'w') {}
+          end
+        end
+      end
+
+      describe 'because the spec is missing' do
+        behaves_like 'it falls back to download the pod'
+      end
+
+      describe 'because the spec is invalid' do
+        before do
+          [@request, @unreleased_request].each do |request|
+            path_for_spec = @cache.send(:path_for_spec, request)
+            path_for_spec.dirname.mkpath
+            path_for_spec.open('w') { |f| f << '{' }
+          end
+        end
+
+        behaves_like 'it falls back to download the pod'
+      end
+    end
+
     describe 'when the download is cached' do
       before do
         [@request, @unreleased_request].each do |request|