5 files changed, 53 insertions, 14 deletions
diff --git a/app/models/ci/build.rb b/app/models/ci/build.rb
index 16a72c680fa..b128a254b96 100644
--- a/app/models/ci/build.rb
+++ b/app/models/ci/build.rb
@@ -10,6 +10,7 @@ module Ci
     include Importable
     include Gitlab::Utils::StrongMemoize
     include Deployable
+    include HasRef
 
     belongs_to :project, inverse_of: :builds
     belongs_to :runner
@@ -640,11 +641,11 @@ module Ci
     def secret_group_variables
       return [] unless project.group
 
-      project.group.ci_variables_for(ref, project)
+      project.group.ci_variables_for(git_ref, project)
     end
 
     def secret_project_variables(environment: persisted_environment)
-      project.ci_variables_for(ref: ref, environment: environment)
+      project.ci_variables_for(ref: git_ref, environment: environment)
     end
 
     def steps
diff --git a/app/models/ci/pipeline.rb b/app/models/ci/pipeline.rb
index 25937065011..1f5017cc3c3 100644
--- a/app/models/ci/pipeline.rb
+++ b/app/models/ci/pipeline.rb
@@ -11,6 +11,7 @@ module Ci
     include Gitlab::Utils::StrongMemoize
     include AtomicInternalId
     include EnumWithNil
+    include HasRef
 
     belongs_to :project, inverse_of: :all_pipelines
     belongs_to :user
@@ -380,7 +381,7 @@ module Ci
     end
 
     def branch?
-      !tag? && !merge_request?
+      super && !merge_request?
     end
 
     def stuck?
@@ -580,7 +581,7 @@ module Ci
     end
 
     def protected_ref?
-      strong_memoize(:protected_ref) { project.protected_for?(ref) }
+      strong_memoize(:protected_ref) { project.protected_for?(git_ref) }
     end
 
     def legacy_trigger
@@ -712,14 +713,10 @@ module Ci
     end
 
     def git_ref
-      if branch?
+      if merge_request?
         Gitlab::Git::BRANCH_REF_PREFIX + ref.to_s
-      elsif merge_request?
-        Gitlab::Git::BRANCH_REF_PREFIX + ref.to_s
-      elsif tag?
-        Gitlab::Git::TAG_REF_PREFIX + ref.to_s
       else
-        raise ArgumentError, 'Invalid pipeline type!'
+        super
       end
     end
 
diff --git a/app/models/concerns/has_ref.rb b/app/models/concerns/has_ref.rb
new file mode 100644
index 00000000000..d7089294efc
--- /dev/null
+++ b/app/models/concerns/has_ref.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module HasRef
+  extend ActiveSupport::Concern
+
+  def branch?
+    !tag?
+  end
+
+  def git_ref
+    if branch?
+      Gitlab::Git::BRANCH_REF_PREFIX + ref.to_s
+    elsif tag?
+      Gitlab::Git::TAG_REF_PREFIX + ref.to_s
+    end
+  end
+end
diff --git a/app/models/project.rb b/app/models/project.rb
index eab19fe4506..cd558752080 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -1733,10 +1733,21 @@ class Project < ActiveRecord::Base
   end
 
   def protected_for?(ref)
-    if repository.branch_exists?(ref)
-      ProtectedBranch.protected?(self, ref)
-    elsif repository.tag_exists?(ref)
-      ProtectedTag.protected?(self, ref)
+    raise Repository::AmbiguousRefError if repository.ambiguous_ref?(ref)
+
+    resolved_ref = repository.expand_ref(ref) || ref
+    return false unless Gitlab::Git.tag_ref?(resolved_ref) || Gitlab::Git.branch_ref?(resolved_ref)
+
+    ref_name = if resolved_ref == ref
+                 Gitlab::Git.ref_name(resolved_ref)
+               else
+                 ref
+               end
+
+    if Gitlab::Git.branch_ref?(resolved_ref)
+      ProtectedBranch.protected?(self, ref_name)
+    elsif Gitlab::Git.tag_ref?(resolved_ref)
+      ProtectedTag.protected?(self, ref_name)
     end
   end
 
diff --git a/app/models/repository.rb b/app/models/repository.rb
index 015a179f374..b19ae2e0e6a 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -25,6 +25,7 @@ class Repository
   delegate :bundle_to_disk, to: :raw_repository
 
   CreateTreeError = Class.new(StandardError)
+  AmbiguousRefError = Class.new(StandardError)
 
   # Methods that cache data from the Git repository.
   #
@@ -181,6 +182,18 @@ class Repository
     tags.find { |tag| tag.name == name }
   end
 
+  def ambiguous_ref?(ref)
+    tag_exists?(ref) && branch_exists?(ref)
+  end
+
+  def expand_ref(ref)
+    if tag_exists?(ref)
+      Gitlab::Git::TAG_REF_PREFIX + ref
+    elsif branch_exists?(ref)
+      Gitlab::Git::BRANCH_REF_PREFIX + ref
+    end
+  end
+
   def add_branch(user, branch_name, ref)
     branch = raw_repository.add_branch(branch_name, user: user, target: ref)