Implement metadata finder for pre-commit (#14222)

* implement metadata finder for precommit

* implement metadata finder for precommit

Author: AbhishekBhaskar

pre_commit/lib/dependabot/pre_commit/metadata_finder.rb

@@ -1,10 +1,7 @@
-# typed: strong
+# typed: strict
 # frozen_string_literal: true
 
-# NOTE: This file was scaffolded automatically but is OPTIONAL.
-# If you don't need custom metadata finding logic (changelogs, release notes, etc.),
-# you can safely delete this file and remove the require from lib/dependabot/pre_commit.rb
-
+require "sorbet-runtime"
 require "dependabot/metadata_finders"
 require "dependabot/metadata_finders/base"
 
@@ -17,9 +14,15 @@ class MetadataFinder < Dependabot::MetadataFinders::Base
 
       sig { override.returns(T.nilable(Dependabot::Source)) }
       def look_up_source
-        # TODO: Implement custom source lookup logic if needed
-        # Otherwise, delete this file and the require in the main registration file
-        nil
+        info = dependency.requirements.filter_map { |r| r[:source] }.first
+
+        url =
+          if info.nil?
+            dependency.name
+          else
+            info[:url] || info.fetch("url")
+          end
+        Source.from_url(url)
       end
     end
   end

pre_commit/spec/dependabot/pre_commit/metadata_finder_spec.rb

@@ -1,6 +1,89 @@
-# typed: strong
+# typed: false
 # frozen_string_literal: true
 
 require "spec_helper"
 require "dependabot/pre_commit/metadata_finder"
 require_common_spec "metadata_finders/shared_examples_for_metadata_finders"
+
+RSpec.describe Dependabot::PreCommit::MetadataFinder do
+  subject(:finder) do
+    described_class.new(dependency: dependency, credentials: credentials)
+  end
+
+  let(:credentials) do
+    [{
+      "type" => "git_source",
+      "host" => "github.com",
+      "username" => "x-access-token",
+      "password" => "token"
+    }]
+  end
+  let(:dependency_source) do
+    {
+      type: "git",
+      url: "https://github.com/pre-commit/pre-commit-hooks",
+      ref: "v4.4.0",
+      branch: nil
+    }
+  end
+  let(:dependency_name) { "https://github.com/pre-commit/pre-commit-hooks" }
+  let(:dependency) do
+    Dependabot::Dependency.new(
+      name: dependency_name,
+      version: "v4.4.0",
+      requirements: [{
+        requirement: nil,
+        groups: [],
+        file: ".pre-commit-config.yaml",
+        source: dependency_source
+      }],
+      package_manager: "pre_commit"
+    )
+  end
+
+  it_behaves_like "a dependency metadata finder"
+
+  describe "#source_url" do
+    subject(:source_url) { finder.source_url }
+
+    context "when dealing with a git source" do
+      let(:dependency_source) do
+        {
+          type: "git",
+          url: "https://github.com/pre-commit/pre-commit-hooks",
+          ref: "v4.4.0",
+          branch: nil
+        }
+      end
+
+      it { is_expected.to eq("https://github.com/pre-commit/pre-commit-hooks") }
+    end
+
+    context "when dealing with a subdependency (no requirements)" do
+      let(:dependency) do
+        Dependabot::Dependency.new(
+          name: dependency_name,
+          version: "v4.4.0",
+          requirements: [],
+          package_manager: "pre_commit"
+        )
+      end
+
+      it { is_expected.to eq("https://github.com/pre-commit/pre-commit-hooks") }
+    end
+
+    context "when dealing with a gitlab source" do
+      let(:dependency_name) { "https://gitlab.com/pycqa/flake8" }
+      let(:dependency_source) do
+        {
+          type: "git",
+          url: "https://gitlab.com/pycqa/flake8",
+          ref: "v5.0.0",
+          branch: nil
+        }
+      end
+
+      it { is_expected.to eq("https://gitlab.com/pycqa/flake8") }
+    end
+  end
+end