Add support for hex ecosystem metrics collection (dependabot#11023)

* Add support for hex ecosystem metrics collection

* Temporarily disable language requirement

* Remove inconsistent language requirement

hex/lib/dependabot/hex/file_parser.rb

@@ -7,12 +7,16 @@
 require "dependabot/file_parsers/base"
 require "dependabot/hex/file_updater/mixfile_sanitizer"
 require "dependabot/hex/native_helpers"
+require "dependabot/hex/language"
+require "dependabot/hex/package_manager"
+require "dependabot/hex/requirement"
 require "dependabot/shared_helpers"
 require "dependabot/errors"
 
 # For docs, see https://hexdocs.pm/mix/Mix.Tasks.Deps.html
 module Dependabot
   module Hex
+    extend T::Sig
     class FileParser < Dependabot::FileParsers::Base
       extend T::Sig
       require "dependabot/file_parsers/base/dependency_set"
@@ -44,6 +48,17 @@ def parse
         dependency_set.dependencies.sort_by(&:name)
       end
 
+      sig { returns(Ecosystem) }
+      def ecosystem
+        @ecosystem ||= T.let(begin
+          Ecosystem.new(
+            name: ECOSYSTEM,
+            package_manager: package_manager,
+            language: language
+          )
+        end, T.nilable(Dependabot::Ecosystem))
+      end
+
       private
 
       sig { returns(T::Array[T.any(T::Hash[String, String], T::Hash[String, T.untyped])]) }
@@ -137,6 +152,43 @@ def mixfiles
       def lockfile
         @lockfile ||= T.let(get_original_file("mix.lock"), T.nilable(Dependabot::DependencyFile))
       end
+
+      sig { returns(Ecosystem::VersionManager) }
+      def package_manager
+        @package_manager ||= T.let(
+          PackageManager.new(hex_version),
+          T.nilable(Dependabot::Hex::PackageManager)
+        )
+      end
+
+      sig { returns(T.nilable(Ecosystem::VersionManager)) }
+      def language
+        @language ||= T.let(
+          Language.new(elixir_version),
+          T.nilable(Dependabot::Hex::Language)
+        )
+      end
+
+      sig { returns(String) }
+      def hex_version
+        T.must(T.must(hex_info).fetch(:hex_version))
+      end
+
+      sig { returns(String) }
+      def elixir_version
+        T.must(T.must(hex_info).fetch(:elixir_version))
+      end
+
+      sig { returns(T.nilable(T::Hash[Symbol, T.nilable(String)])) }
+      def hex_info
+        @hex_info ||= T.let(begin
+          version = SharedHelpers.run_shell_command("mix hex.info")
+          {
+            hex_version: version.match(/Hex: \s*(\d+\.\d+(.\d+)*)/)&.captures&.first,
+            elixir_version: version.match(/Elixir: \s*(\d+\.\d+(.\d+)*)/)&.captures&.first
+          }
+        end, T.nilable(T::Hash[Symbol, T.nilable(String)]))
+      end
     end
   end
 end

hex/lib/dependabot/hex/language.rb

@@ -0,0 +1,21 @@
+# typed: strong
+# frozen_string_literal: true
+
+require "sorbet-runtime"
+require "dependabot/ecosystem"
+require "dependabot/hex/version"
+
+module Dependabot
+  module Hex
+    LANGUAGE = "elixir"
+
+    class Language < Dependabot::Ecosystem::VersionManager
+      extend T::Sig
+
+      sig { params(raw_version: String).void }
+      def initialize(raw_version)
+        super(LANGUAGE, Version.new(raw_version))
+      end
+    end
+  end
+end

hex/lib/dependabot/hex/package_manager.rb

@@ -0,0 +1,41 @@
+# typed: strong
+# frozen_string_literal: true
+
+require "sorbet-runtime"
+require "dependabot/ecosystem"
+require "dependabot/hex/version"
+
+module Dependabot
+  module Hex
+    ECOSYSTEM = "hex"
+    PACKAGE_MANAGER = "hex"
+    SUPPORTED_HEX_VERSIONS = T.let([].freeze, T::Array[Dependabot::Version])
+
+    # When a version is going to be unsupported, it will be added here
+    DEPRECATED_HEX_VERSIONS = T.let([].freeze, T::Array[Dependabot::Version])
+
+    class PackageManager < Dependabot::Ecosystem::VersionManager
+      extend T::Sig
+
+      sig { params(raw_version: String).void }
+      def initialize(raw_version)
+        super(
+          PACKAGE_MANAGER,
+          Version.new(raw_version),
+          DEPRECATED_HEX_VERSIONS,
+          SUPPORTED_HEX_VERSIONS
+        )
+      end
+
+      sig { returns(T::Boolean) }
+      def deprecated?
+        false
+      end
+
+      sig { returns(T::Boolean) }
+      def unsupported?
+        false
+      end
+    end
+  end
+end

hex/spec/dependabot/hex/file_parser_spec.rb

@@ -452,4 +452,32 @@
       end
     end
   end
+
+  describe "#ecosystem" do
+    subject(:ecosystem) { parser.ecosystem }
+
+    it "has the correct name" do
+      expect(ecosystem.name).to eq "hex"
+    end
+
+    describe "#package_manager" do
+      subject(:package_manager) { ecosystem.package_manager }
+
+      it "returns the correct package manager" do
+        expect(package_manager.name).to eq "hex"
+        expect(package_manager.requirement).to be_nil
+        expect(package_manager.version.to_s).to eq "2.0.6"
+      end
+    end
+
+    describe "#language" do
+      subject(:language) { ecosystem.language }
+
+      it "returns the correct language" do
+        expect(language.name).to eq "elixir"
+        expect(language.requirement).to be_nil
+        expect(language.version.to_s).to eq "1.14.4"
+      end
+    end
+  end
 end

hex/spec/dependabot/hex/language_spec.rb

@@ -0,0 +1,36 @@
+# typed: false
+# frozen_string_literal: true
+
+require "dependabot/hex/language"
+require "dependabot/ecosystem"
+require "spec_helper"
+
+RSpec.describe Dependabot::Hex::Language do
+  subject(:language) { described_class.new(version) }
+
+  let(:version) { "1.17.3" }
+
+  describe "#version" do
+    it "returns the version" do
+      expect(language.version).to eq(Dependabot::Hex::Version.new(version))
+    end
+  end
+
+  describe "#name" do
+    it "returns the name" do
+      expect(language.name).to eq(Dependabot::Hex::LANGUAGE)
+    end
+  end
+
+  describe "#unsupported?" do
+    it "returns false by default" do
+      expect(language.unsupported?).to be false
+    end
+  end
+
+  describe "#deprecated?" do
+    it "returns false by default" do
+      expect(language.deprecated?).to be false
+    end
+  end
+end

hex/spec/dependabot/hex/package_manager_spec.rb

@@ -0,0 +1,36 @@
+# typed: false
+# frozen_string_literal: true
+
+require "dependabot/hex/package_manager"
+require "dependabot/ecosystem"
+require "spec_helper"
+
+RSpec.describe Dependabot::Hex::PackageManager do
+  subject(:package_manager) { described_class.new(version) }
+
+  let(:version) { "2.1.1" }
+
+  describe "#version" do
+    it "returns the version" do
+      expect(package_manager.version).to eq(Dependabot::Hex::Version.new(version))
+    end
+  end
+
+  describe "#name" do
+    it "returns the name" do
+      expect(package_manager.name).to eq(Dependabot::Hex::PACKAGE_MANAGER)
+    end
+  end
+
+  describe "#deprecated_versions" do
+    it "returns deprecated versions" do
+      expect(package_manager.deprecated_versions).to eq(Dependabot::Hex::DEPRECATED_HEX_VERSIONS)
+    end
+  end
+
+  describe "#supported_versions" do
+    it "returns supported versions" do
+      expect(package_manager.supported_versions).to eq(Dependabot::Hex::SUPPORTED_HEX_VERSIONS)
+    end
+  end
+end