Remove the native go helper

There are two functions that do the same thing, one in `ruby` and one in
`go`.

TODO explain why we had them both and why safe to remove the `go` one
once I finish researching it.

So I removed the one written in `go`.

It turns out this function was the only reason we had native `go`
helpers, so I was able to completely remove the helpers infra altogether.

Fix dependabot#4448

.github/dependabot.yml

@@ -92,10 +92,6 @@ updates:
     directory: "/"
     schedule:
       interval: "weekly"
-  - package-ecosystem: "gomod"
-    directory: "/go_modules/helpers"
-    schedule:
-      interval: "weekly"
   - package-ecosystem: "mix"
     directory: "/hex/helpers"
     schedule:

Dockerfile

@@ -266,7 +266,6 @@ RUN DART_ARCH=${TARGETARCH} \
 COPY --chown=dependabot:dependabot LICENSE /home/dependabot
 COPY --chown=dependabot:dependabot composer/helpers /opt/composer/helpers
 COPY --chown=dependabot:dependabot bundler/helpers /opt/bundler/helpers
-COPY --chown=dependabot:dependabot go_modules/helpers /opt/go_modules/helpers
 COPY --chown=dependabot:dependabot hex/helpers /opt/hex/helpers
 COPY --chown=dependabot:dependabot pub/helpers /opt/pub/helpers
 COPY --chown=dependabot:dependabot npm_and_yarn/helpers /opt/npm_and_yarn/helpers
@@ -282,7 +281,6 @@ RUN bash /opt/bundler/helpers/v1/build
 RUN bash /opt/bundler/helpers/v2/build
 RUN bash /opt/composer/helpers/v1/build
 RUN bash /opt/composer/helpers/v2/build
-RUN bash /opt/go_modules/helpers/build
 RUN bash /opt/hex/helpers/build
 RUN bash /opt/npm_and_yarn/helpers/build
 RUN bash /opt/pub/helpers/build

bin/docker-dev-shell

@@ -191,7 +191,6 @@ docker run --rm -ti \
   -v "$(pwd)/go_modules/.rubocop.yml:$CODE_DIR/go_modules/.rubocop.yml" \
   -v "$(pwd)/go_modules/Gemfile:$CODE_DIR/go_modules/Gemfile" \
   -v "$(pwd)/go_modules/dependabot-go_modules.gemspec:$CODE_DIR/go_modules/dependabot-go_modules.gemspec" \
-  -v "$(pwd)/go_modules/helpers:$CODE_DIR/go_modules/helpers" \
   -v "$(pwd)/go_modules/lib:$CODE_DIR/go_modules/lib" \
   -v "$(pwd)/go_modules/spec:$CODE_DIR/go_modules/spec" \
   -v "$(pwd)/go_modules/script:$CODE_DIR/go_modules/script" \

go_modules/lib/dependabot/go_modules/metadata_finder.rb

@@ -13,8 +13,7 @@ def look_up_source
         return look_up_git_dependency_source if git_dependency?
 
         path_str = (specified_source_string || dependency.name)
-        url = Dependabot::GoModules::PathConverter.
-              git_url_for_path_without_go_helper(path_str)
+        url = Dependabot::GoModules::PathConverter.git_url_for_path(path_str)
         Source.from_url(url) if url
       end
 

go_modules/lib/dependabot/go_modules/path_converter.rb

@@ -10,22 +10,8 @@
 module Dependabot
   module GoModules
     module PathConverter
-      def self.git_url_for_path(path)
-        # Save a query by manually converting golang.org/x names
-        import_path = path.gsub(%r{^golang\.org/x}, "github.com/golang")
-
-        SharedHelpers.run_helper_subprocess(
-          command: NativeHelpers.helper_path,
-          function: "getVcsRemoteForImport",
-          args: { import: import_path }
-        )
-      end
-
       # rubocop:disable Metrics/PerceivedComplexity
-      # Used in dependabot-backend, which doesn't have access to any Go
-      # helpers.
-      # TODO: remove the need for this.
-      def self.git_url_for_path_without_go_helper(path)
+      def self.git_url_for_path(path)
         # Save a query by manually converting golang.org/x names
         tmp_path = path.gsub(%r{^golang\.org/x}, "github.com/golang")
 
@@ -56,8 +42,8 @@ def self.git_url_for_path_without_go_helper(path)
       # rubocop:enable Metrics/PerceivedComplexity
 
       def self.fetch_path_metadata(path)
-        # TODO: This is not robust! Instead, we should shell out to Go and
-        # use https://github.com/Masterminds/vcs.
+        # TODO: update this comment to explain why it's leveraging the `go-get=1` trick
+        # and why may not be robust
         response = Dependabot::RegistryClient.get(url: "https://#{path}?go-get=1")
 
         return unless response.status == 200

go_modules/spec/dependabot/go_modules/path_converter_spec.rb

@@ -29,6 +29,32 @@
       it { is_expected.to eq("https://github.com/kubernetes/apimachinery") }
     end
 
+
+    # TODO below was test case for ruby helper, above is test case for native go helper
+    # notice the extra fixture stubbing required for Ruby, figure out how robust this is...
+    #
+    # context "with a vanity URL that needs to be fetched" do
+    #   let(:path) { "k8s.io/apimachinery" }
+
+    #   before do
+    #     stub_request(:get, "https://k8s.io/apimachinery?go-get=1").
+    #       to_return(status: 200, body: vanity_response)
+    #   end
+    #   let(:vanity_response) do
+    #     fixture("repo_responses", "k8s_io_apimachinery.html")
+    #   end
+
+    #   it { is_expected.to eq("https://github.com/kubernetes/apimachinery") }
+
+    #   context "and returns a git source hosted with an unknown provider" do
+    #     let(:vanity_response) do
+    #       fixture("go", "repo_responses", "unknown_git_source.html")
+
+    #       it { is_expected.to eq("https://sf.com/kubernetes/apimachinery") }
+    #     end
+    #   end
+    # end
+
     xcontext "with a vanity URL that redirects" do
       let(:path) { "code.cloudfoundry.org/bytefmt" }
       it { is_expected.to eq("https://github.com/cloudfoundry/bytefmt") }
@@ -44,47 +70,4 @@
       it { is_expected.to eq("https://github.com/drewolson/testflight") }
     end
   end
-
-  describe ".git_url_for_path_without_go_helper" do
-    subject { described_class.git_url_for_path_without_go_helper(path) }
-
-    let(:path) { "gopkg.in/guregu/null.v3" }
-
-    context "with a path that is immediately recognisable as a git source" do
-      let(:path) { "github.com/drewolson/testflight" }
-      it { is_expected.to eq("https://github.com/drewolson/testflight") }
-    end
-
-    context "with a golang.org path" do
-      let(:path) { "golang.org/x/tools" }
-      it { is_expected.to eq("https://github.com/golang/tools") }
-    end
-
-    context "with a path that ends in .git" do
-      let(:path) { "git.fd.io/govpp.git" }
-      it { is_expected.to eq("https://git.fd.io/govpp.git") }
-    end
-
-    context "with a vanity URL that needs to be fetched" do
-      let(:path) { "k8s.io/apimachinery" }
-
-      before do
-        stub_request(:get, "https://k8s.io/apimachinery?go-get=1").
-          to_return(status: 200, body: vanity_response)
-      end
-      let(:vanity_response) do
-        fixture("repo_responses", "k8s_io_apimachinery.html")
-      end
-
-      it { is_expected.to eq("https://github.com/kubernetes/apimachinery") }
-
-      context "and returns a git source hosted with an unknown provider" do
-        let(:vanity_response) do
-          fixture("go", "repo_responses", "unknown_git_source.html")
-
-          it { is_expected.to eq("https://sf.com/kubernetes/apimachinery") }
-        end
-      end
-    end
-  end
 end