Dep: Add basic MetadataFinder

lib/dependabot/metadata_finders/go/dep.rb

@@ -9,9 +9,22 @@ class Dep < Dependabot::MetadataFinders::Base
         private
 
         def look_up_source
-          # Hit the registry (or some other source) and get details of the
-          # location of the source code for the given dependency
-          Source.new(host: "github.com", repo: "my-org/my-dependency")
+          # TODO: A more general way to do this?
+          source_string = specified_source_string.
+                          gsub(%r{^golang\.org/x}, "github.com/golang")
+
+          Source.from_url(source_string)
+        end
+
+        def specified_source_string
+          sources = dependency.requirements.
+                    map { |r| r.fetch(:source) }.uniq.compact
+
+          raise "Multiple sources! #{sources.join(', ')}" if sources.count > 1
+
+          sources.first&.fetch(:source, nil) ||
+            sources.first&.fetch("source") ||
+            dependency.name
         end
       end
     end

spec/dependabot/metadata_finders/go/dep_spec.rb

@@ -1,8 +1,69 @@
 # frozen_string_literal: true
 
+require "dependabot/dependency"
 require "dependabot/metadata_finders/go/dep"
 require_relative "../shared_examples_for_metadata_finders"
 
 RSpec.describe Dependabot::MetadataFinders::Go::Dep do
   it_behaves_like "a dependency metadata finder"
+
+  let(:dependency) do
+    Dependabot::Dependency.new(
+      name: dependency_name,
+      version: "2.1.0",
+      requirements: requirements,
+      package_manager: "dep"
+    )
+  end
+  let(:requirements) do
+    [{
+      file: "Gopkg.toml",
+      requirement: "v2.1.0",
+      groups: [],
+      source: source
+    }]
+  end
+  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_name) { "github.com/satori/go.uuid" }
+  let(:source) { nil }
+
+  describe "#source_url" do
+    subject(:source_url) { finder.source_url }
+
+    context "with a github name" do
+      it { is_expected.to eq("https://github.com/satori/go.uuid") }
+
+      context "and no requirements" do
+        it { is_expected.to eq("https://github.com/satori/go.uuid") }
+      end
+
+      context "that uses golang.org" do
+        let(:dependency_name) { "golang.org/x/text" }
+        it { is_expected.to eq("https://github.com/golang/text") }
+      end
+    end
+
+    context "with a source" do
+      let(:source) do
+        {
+          type: "default",
+          source: "github.com/alias/go.uuid",
+          branch: nil,
+          ref: nil
+        }
+      end
+
+      it { is_expected.to eq("https://github.com/alias/go.uuid") }
+    end
+  end
 end