[Podfile] Change the default spec repository to the master

Closes #2946

CHANGELOG.md

@@ -6,6 +6,14 @@ To install release candidates run `[sudo] gem install cocoapods --pre`
 
 ## Master
 
+##### Breaking
+
+* Changes the default spec repositories used from all configured spec
+  repositories, to the master spec repository when no spec repositories
+  are explicitly configured in a Podfile.  
+  [Kyle Fuller](https://github.com/kylef)
+  [#2946](https://github.com/CocoaPods/CocoaPods/issues/2946)
+
 ##### Enhancements
 
 * Xcodebuild warnings will now be reported as `warning` during linting
@@ -23,6 +31,12 @@ To install release candidates run `[sudo] gem install cocoapods --pre`
   [#2981](https://github.com/CocoaPods/CocoaPods/issues/2981)
   [cocoapods-trunk#33](https://github.com/CocoaPods/cocoapods-trunk/issues/33)
 
+* Clone the master spec repository when no spec repositories are explicitly
+  defined in the Podfile. This fixes problems using CocoaPods for the first
+  time without any explicit spec repositories.  
+  [Kyle Fuller](https://github.com/kylef)
+  [#2946](https://github.com/CocoaPods/CocoaPods/issues/2946)
+
 * Xcodebuild warnings with the string `error` in them will no longer be
   linted as errors if they are in fact warnings.  
   [Hugo Tunius](https://github.com/K0nserv)

lib/cocoapods/installer/analyzer.rb

@@ -465,7 +465,8 @@ module Pod
 
       # Returns the sources used to query for specifications
       #
-      # When no explicit Podfile sources are defined, this defaults to all
+      # When no explicit Podfile sources are defined, this defaults to the
+      # master spec repository.
       # available sources ({SourcesManager.all}).
       #
       # @return [Array<Source>] the sources to be used in finding
@@ -475,7 +476,8 @@ module Pod
         @sources ||= begin
           sources = podfile.sources
           if sources.empty?
-            SourcesManager.all
+            url = 'https://github.com/CocoaPods/Specs.git'
+            [SourcesManager.find_or_create_source_with_url(url)]
           else
             sources.map do |url|
               SourcesManager.find_or_create_source_with_url(url)

spec/unit/installer/analyzer_spec.rb

@@ -54,7 +54,7 @@ module Pod
 
       it 'updates the repositories by default' do
         config.skip_repo_update = false
-        SourcesManager.expects(:update).twice
+        SourcesManager.expects(:update).once
         @analyzer.analyze
       end
 
@@ -552,9 +552,9 @@ module Pod
 
         describe '#sources' do
           describe 'when there are no explicit sources' do
-            it 'defaults to all sources' do
+            it 'defaults to the master spec repository' do
               @analyzer.send(:sources).map(&:url).should ==
-                SourcesManager.all.map(&:url)
+                ['https://github.com/CocoaPods/Specs.git']
             end
           end