Check GitHub API rate limit instead of silently failing

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

Library/Contributions/cmd/brew-ls-taps.rb

@@ -1,7 +1,7 @@
 require 'vendor/multi_json'
 
-begin
-  GitHub.open "https://api.github.com/legacy/repos/search/homebrew" do |f|
+GitHub.open "https://api.github.com/legacy/repos/search/homebrew" do |f|
+  begin
     MultiJson.decode(f.read)["repositories"].each do |repo|
       if repo['name'] =~ /^homebrew-(\S+)$/
         puts tap = if repo['username'] == "Homebrew"
@@ -11,7 +11,6 @@ begin
         end
       end
     end
+  rescue
   end
-rescue
-  nil
 end

Library/Homebrew/cmd/search.rb

@@ -64,6 +64,7 @@ module Homebrew extend self
 
     results = []
     GitHub.open "https://api.github.com/repos/#{user}/homebrew-#{repo}/git/trees/HEAD?recursive=1" do |f|
+      begin
         user.downcase! if user == "Homebrew" # special handling for the Homebrew organization
         MultiJson.decode(f.read)["tree"].map{ |hash| hash['path'] }.compact.each do |file|
           name = File.basename(file, '.rb')
@@ -72,10 +73,10 @@ module Homebrew extend self
             $found += 1
           end
         end
+      rescue
+      end
     end
     results
-  rescue
-    []
   end
 
   def search_brews rx

Library/Homebrew/utils.rb

@@ -259,7 +259,16 @@ end
 module GitHub extend self
   def open url, headers={}, &block
     require 'open-uri'
-    Kernel.open(url, headers.merge('User-Agent' => HOMEBREW_USER_AGENT), &block)
+    begin
+      Kernel.open(url, {'User-Agent' => HOMEBREW_USER_AGENT}.merge(headers), &block)
+    rescue OpenURI::HTTPError => e
+      if e.io.meta['x-ratelimit-remaining'].to_i <= 0
+        require 'vendor/multi_json'
+        raise "GitHub #{MultiJson.decode(e.io.read)['message']}"
+      else
+        raise e
+      end
+    end
   end
   
   def issues_for_formula name
@@ -276,15 +285,16 @@ module GitHub extend self
     uri = URI.parse("https://api.github.com/legacy/issues/search/mxcl/homebrew/open/#{name}")
 
     open uri do |f|
+      begin
         MultiJson.decode(f.read)['issues'].each do |issue|
           # don't include issues that just refer to the tool in their body
           issues << issue['html_url'] if issue['title'].include? name
         end
+      rescue
+      end
     end
 
     issues
-  rescue
-    []
   end
 
   def find_pull_requests rx
@@ -294,11 +304,12 @@ module GitHub extend self
     uri = URI.parse("https://api.github.com/legacy/issues/search/mxcl/homebrew/open/#{query}")
 
     GitHub.open uri do |f|
+      begin
         MultiJson.decode(f.read)['issues'].each do |pull|
           yield pull['pull_request_url'] if rx.match pull['title'] and pull['pull_request_url']
         end
-    end
       rescue
-    nil
+      end
+    end
   end
 end