Refactors

app/graphql/resolvers/last_commit_resolver.rb

@@ -12,7 +12,7 @@ def resolve(**args)
       # Ensure merge commits can be returned by sending nil to Gitaly instead of '/'
       path = tree.path == '/' ? nil : tree.path
       commit = Gitlab::Git::Commit.last_for_path(tree.repository,
-        tree.ref_type.present? ? "refs/#{tree.ref_type}/#{tree.sha}" : tree.sha, path, literal_pathspec: true)
+        ExtractsRef.fully_qualified_ref(tree.sha, tree.ref_type), path, literal_pathspec: true)
 
       ::Commit.new(commit, tree.repository.project) if commit
     end

app/graphql/resolvers/paginated_tree_resolver.rb

@@ -20,7 +20,7 @@ class PaginatedTreeResolver < BaseResolver
               description: 'Commit ref to get the tree for. Default value is HEAD.'
     argument :ref_type, GraphQL::Types::String,
               required: false,
-              description: 'ref type.'
+              description: 'Type of the ref. heads for branches and tags for tags.'
 
     alias_method :repository, :object
 

app/graphql/resolvers/tree_resolver.rb

@@ -19,7 +19,7 @@ class TreeResolver < BaseResolver
               description: 'Commit ref to get the tree for. Default value is HEAD.'
     argument :ref_type, GraphQL::Types::String,
               required: false,
-              description: 'ref type.'
+              description: 'Type of the ref. heads for branches and tags for tags.'
 
     alias_method :repository, :object
 

app/models/tree.rb

@@ -13,18 +13,18 @@ def initialize(
     @repository = repository
     @sha = sha
     @path = path
-    @ref_type = ref_type
+    @ref_type = ExtractsRef.ref_type(ref_type)
     git_repo = @repository.raw_repository
-    ref = @sha
 
-    if ref_type.present?
-      @ref_type = ref_type == 'heads' ? 'heads' : 'tags'
-      ref = "refs/#{@ref_type}/#{@sha}"
-    end
+    ref = if ref_type.present?
+            ExtractsRef.fully_qualified_ref(@sha, ref_type)
+          else
+            @sha
+          end
 
     @entries, @cursor = Gitlab::Git::Tree.where(git_repo, ref, @path, recursive, skip_flat_paths, pagination_params)
     @entries.each do |entry|
-      entry.ref_type = ref_type
+      entry.ref_type = @ref_type
     end
   end
 

doc/api/graphql/reference/index.md

@@ -21464,7 +21464,7 @@ four standard [pagination arguments](#connection-pagination-arguments):
 | <a id="repositorypaginatedtreepath"></a>`path` | [`String`](#string) | Path to get the tree for. Default value is the root of the repository. |
 | <a id="repositorypaginatedtreerecursive"></a>`recursive` | [`Boolean`](#boolean) | Used to get a recursive tree. Default is false. |
 | <a id="repositorypaginatedtreeref"></a>`ref` | [`String`](#string) | Commit ref to get the tree for. Default value is HEAD. |
-| <a id="repositorypaginatedtreereftype"></a>`refType` | [`String`](#string) | ref type. |
+| <a id="repositorypaginatedtreereftype"></a>`refType` | [`String`](#string) | Type of the ref. heads for branches and tags for tags. |
 ##### `Repository.tree`
@@ -21479,7 +21479,7 @@ Returns [`Tree`](#tree).
 | <a id="repositorytreepath"></a>`path` | [`String`](#string) | Path to get the tree for. Default value is the root of the repository. |
 | <a id="repositorytreerecursive"></a>`recursive` | [`Boolean`](#boolean) | Used to get a recursive tree. Default is false. |
 | <a id="repositorytreeref"></a>`ref` | [`String`](#string) | Commit ref to get the tree for. Default value is HEAD. |
-| <a id="repositorytreereftype"></a>`refType` | [`String`](#string) | ref type. |
+| <a id="repositorytreereftype"></a>`refType` | [`String`](#string) | Type of the ref. heads for branches and tags for tags. |
 ### `RepositoryBlob`

lib/extracts_ref.rb

@@ -7,6 +7,8 @@ module ExtractsRef
   InvalidPathError = Class.new(StandardError)
   BRANCH_REF_TYPE = 'heads'
   TAG_REF_TYPE = 'tags'
+  REF_TYPES = [BRANCH_REF_TYPE, TAG_REF_TYPE].freeze
+
   # Given a string containing both a Git tree-ish, such as a branch or tag, and
   # a filesystem path joined by forward slashes, attempts to separate the two.
   #
@@ -60,7 +62,6 @@ def extract_ref(id)
   #
   # If the :id parameter appears to be requesting a specific response format,
   # that will be handled as well.
-  #
   # rubocop:disable Gitlab/ModuleWithInstanceVariables
   def assign_ref_vars
     @id, @ref, @path = extract_ref_path
@@ -70,7 +71,7 @@ def assign_ref_vars
     return unless @ref.present?
 
     @commit = if ref_type
-                @fully_qualified_ref = %(refs/#{ref_type}/#{@ref})
+                @fully_qualified_ref = ExtractsRef.fully_qualified_ref(@ref, ref_type)
                 @repo.commit(@fully_qualified_ref)
               else
                 @repo.commit(@ref)
@@ -90,9 +91,20 @@ def extract_ref_path
   end
 
   def ref_type
-    return unless params[:ref_type].present?
+    ExtractsRef.ref_type(params[:ref_type])
+  end
+
+  def self.ref_type(type)
+    return unless REF_TYPES.include?(type)
+
+    type
+  end
+
+  def self.fully_qualified_ref(ref, type)
+    validated_type = ref_type(type)
+    return ref unless validated_type
 
-    params[:ref_type] == TAG_REF_TYPE ? TAG_REF_TYPE : BRANCH_REF_TYPE
+    %(refs/#{validated_type}/#{ref})
   end
 
   private
@@ -156,6 +168,7 @@ def repository_container
     raise NotImplementedError
   end
 
+  # deprecated in favor of ExtractsRef::RequestedRef
   def ambiguous_ref?(project, ref)
     return true if project.repository.ambiguous_ref?(ref)
 

spec/lib/extracts_ref_spec.rb

@@ -57,5 +57,64 @@
     end
   end
 
+  describe '#ref_type' do
+    let(:params) { ActionController::Parameters.new(ref_type: 'heads') }
+
+    it 'delegates to .ref_type' do
+      expect(described_class).to receive(:ref_type).with('heads')
+      ref_type
+    end
+  end
+
+  describe '.ref_type' do
+    subject { described_class.ref_type(ref_type) }
+
+    context 'when ref_type is nil' do
+      let(:ref_type) { nil }
+
+      it { is_expected.to eq(nil) }
+    end
+
+    context 'when ref_type is heads' do
+      let(:ref_type) { 'heads' }
+
+      it { is_expected.to eq('heads') }
+    end
+
+    context 'when ref_type is tags' do
+      let(:ref_type) { 'tags' }
+
+      it { is_expected.to eq('tags') }
+    end
+
+    context 'when ref_type is invalid' do
+      let(:ref_type) { 'invalid' }
+
+      it { is_expected.to eq(nil) }
+    end
+  end
+
+  describe '.fully_qualified_ref' do
+    subject { described_class.fully_qualified_ref(ref, ref_type) }
+
+    context 'when ref_type is nil' do
+      let(:ref_type) { nil }
+
+      it { is_expected.to eq(ref) }
+    end
+
+    context 'when ref_type valid' do
+      let(:ref_type) { 'heads' }
+
+      it { is_expected.to eq("refs/#{ref_type}/#{ref}") }
+    end
+
+    context 'when ref_type is invalid' do
+      let(:ref_type) { 'invalid' }
+
+      it { is_expected.to eq(ref) }
+    end
+  end
+
   it_behaves_like 'extracts refs'
 end