Merge pull request #5001 from dependabot/translate-types-to-libraries

Map Package Name to Types Package Name

npm_and_yarn/lib/dependabot/npm_and_yarn/package_name.rb

@@ -0,0 +1,63 @@
+# frozen_string_literal: true
+
+module Dependabot
+  module NpmAndYarn
+    class PackageName
+      DEFINITELY_TYPED_SCOPE = /types/i.freeze
+      PACKAGE_NAME_REGEX     = %r{
+          \A                                         # beginning of string
+          (?=.{1,214}\z)                             # enforce length (1 - 214)
+          (@(?<scope>[a-z0-9\-~][a-z0-9\-\._~]*)\/)? # capture 'scope' if present
+          (?<name>[a-z0-9\-~][a-z0-9\-._~]*)         # capture package name
+          \z                                         # end of string
+      }xi.freeze                                     # multi-line/case-insensitive
+
+      class InvalidPackageName < StandardError; end
+
+      def initialize(string)
+        match = PACKAGE_NAME_REGEX.match(string.to_s)
+        raise InvalidPackageName unless match
+
+        @scope = match[:scope]
+        @name  = match[:name]
+      end
+
+      def to_s
+        if scoped?
+          "@#{@scope}/#{@name}"
+        else
+          @name.to_s
+        end
+      end
+
+      def <=>(other)
+        to_s.casecmp(other.to_s)
+      end
+
+      def eql?(other)
+        to_s.eql?(other.to_s)
+      end
+
+      def types_package_name
+        return self if types_package?
+
+        @types_package_name ||=
+          if scoped?
+            self.class.new("@types/#{@scope}__#{@name}")
+          else
+            self.class.new("@types/#{@name}")
+          end
+      end
+
+      private
+
+      def scoped?
+        !@scope.nil?
+      end
+
+      def types_package?
+        DEFINITELY_TYPED_SCOPE.match?(@scope)
+      end
+    end
+  end
+end

npm_and_yarn/spec/dependabot/npm_and_yarn/package_name_spec.rb

@@ -0,0 +1,121 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+require "dependabot/npm_and_yarn/package_name"
+
+RSpec.describe Dependabot::NpmAndYarn::PackageName do
+  describe "initialization" do
+    it "raises a meaningful error if the input is not a valid package name" do
+      expect { described_class.new("🤷") }.to raise_error(described_class::InvalidPackageName)
+      expect { described_class.new([]) }.to raise_error(described_class::InvalidPackageName)
+      expect { described_class.new({}) }.to raise_error(described_class::InvalidPackageName)
+      expect { described_class.new(nil) }.to raise_error(described_class::InvalidPackageName)
+      expect { described_class.new("") }.to raise_error(described_class::InvalidPackageName)
+      expect { described_class.new(" prefixed-with-a-space") }.to raise_error(described_class::InvalidPackageName)
+      expect { described_class.new(".prefixed-with-a-dot") }.to raise_error(described_class::InvalidPackageName)
+      expect { described_class.new("!invalid") }.to raise_error(described_class::InvalidPackageName)
+    end
+  end
+
+  describe "#to_s" do
+    it "returns the name when no scope is present" do
+      jquery = "jquery"
+
+      package_name = described_class.new(jquery).to_s
+
+      expect(package_name).to eq(jquery)
+    end
+
+    it "returns the name with scope when a scope is present" do
+      babel_core = "@babel/core"
+
+      package_name_with_scope = described_class.new(babel_core).to_s
+
+      expect(package_name_with_scope).to eq(babel_core)
+    end
+  end
+
+  describe "#types_package_name" do
+    it "returns the corresponding types package name" do
+      lodash       = "lodash"
+      lodash_types = "@types/lodash"
+
+      types_package_name = described_class.new(lodash).types_package_name
+
+      expect(types_package_name.to_s).to eq(lodash_types)
+    end
+
+    it "returns self if it is already a types package" do
+      stereo_types = "@types/stereo"
+
+      types_package_name = described_class.new(stereo_types).types_package_name
+
+      expect(types_package_name.to_s).to eq(stereo_types)
+    end
+
+    context "when given a scoped dependency name" do
+      it "returns the corresponding scoped types package name" do
+        babel_core       = "@babel/core"
+        babel_core_types = "@types/babel__core"
+
+        types_package_name = described_class.new(babel_core).types_package_name
+
+        expect(types_package_name.to_s).to eq(babel_core_types)
+      end
+    end
+  end
+
+  describe "#eql?" do
+    it "compares the string representation of the package name" do
+      package       = described_class.new("package")
+      package_again = described_class.new("package")
+
+      equality_check = package.eql?(package_again)
+
+      expect(equality_check).to be true
+    end
+
+    it "returns true for equivalent package names" do
+      react       = described_class.new("react")
+      react_again = described_class.new("react")
+
+      equality_check = react.eql?(react_again)
+
+      expect(equality_check).to be true
+    end
+
+    it "returns false for non-equivalent package names" do
+      react = described_class.new("react")
+      vue   = described_class.new("vue")
+
+      equality_check = react.eql?(vue)
+
+      expect(equality_check).to be false
+    end
+  end
+
+  describe "#<=>" do
+    it "provides affordances for sorting/comparison" do
+      first  = described_class.new("first")
+      second = described_class.new("second")
+      third  = described_class.new("third")
+
+      expect([third, second, first].sort).to eq([first, second, third])
+    end
+
+    it "ignores case" do
+      package_name_string = "jquery"
+      all_caps  = described_class.new(package_name_string.upcase)
+      all_lower = described_class.new(package_name_string.downcase)
+
+      expect(all_lower <=> all_caps).to be_zero
+    end
+
+    it "allows for comparison with types packages" do
+      library = described_class.new("my-library")
+
+      expect([library, library.types_package_name].sort).
+        to eq([library.types_package_name, library])
+    end
+  end
+end