Merge pull request #3229 from BenMusch/check-for-master-no-refactor

doctor: Check for branch of core tap (take 2)

3 files changed, 27 insertions, 0 deletions

diff --git a/Library/Homebrew/diagnostic.rb b/Library/Homebrew/diagnostic.rb
index baf04e332..9ab83c1a2 100644
--- a/Library/Homebrew/diagnostic.rb
+++ b/Library/Homebrew/diagnostic.rb
@@ -787,6 +787,18 @@ module Homebrew
               git -C "#{coretap_path}" remote set-url origin #{Formatter.url("https://github.com/Homebrew/homebrew-core.git")}
           EOS
         end
+
+        return if ENV["CI"] || ENV["JENKINS_HOME"]
+
+        branch = coretap_path.git_branch
+        return if branch.nil? || branch =~ /master/
+
+        <<-EOS.undent
+          Homebrew/homebrew-core is not on the master branch
+
+          Check out the master branch by running:
+            git -C "$(brew --repo homebrew/core)" checkout master
+        EOS
       end
 
       def __check_linked_brew(f)
diff --git a/Library/Homebrew/extend/git_repository.rb b/Library/Homebrew/extend/git_repository.rb
index c15988550..6b89d175c 100644
--- a/Library/Homebrew/extend/git_repository.rb
+++ b/Library/Homebrew/extend/git_repository.rb
@@ -36,6 +36,15 @@ module GitRepositoryExtension
     end
   end
 
+  def git_branch
+    return unless git? && Utils.git_available?
+    cd do
+      Utils.popen_read(
+        "git", "rev-parse", "--abbrev-ref", "HEAD"
+      ).chuzzle
+    end
+  end
+
   def git_last_commit_date
     return unless git? && Utils.git_available?
     cd do
diff --git a/Library/Homebrew/tap.rb b/Library/Homebrew/tap.rb
index 4b3cfc38a..c12c121e4 100644
--- a/Library/Homebrew/tap.rb
+++ b/Library/Homebrew/tap.rb
@@ -115,6 +115,12 @@ class Tap
     path.git?
   end
 
+  # git branch for this {Tap}.
+  def git_branch
+    raise TapUnavailableError, name unless installed?
+    path.git_branch
+  end
+
   # git HEAD for this {Tap}.
   def git_head
     raise TapUnavailableError, name unless installed?