fix: only use Yarn Classic when major version is 1 (#7)

ahangarha · G-Rath · web-flow · commit 19c35a2c02df · 2023-10-04T13:00:15.000+13:00
* Ensure yarn classic is detected only with version 1

* Add support for range version using ~ and ^ for yarn

* Limit regex repetition wild card

* Add explanatory comment for regex

* Fix rubocop issue

* Simplify regex

* Move tests under .read tests

* Remove redundant variable and improve comments

Co-authored-by: Gareth Jones &lt;Jones258@Gmail.com&gt;

* Improve test titles

* Remove redundant test

* Fix regex for version constraints

* Add test for exact version

* test: update example

* chore: address typo

---------

Co-authored-by: Gareth Jones &lt;Jones258@Gmail.com&gt;
diff --git a/lib/package_json.rb b/lib/package_json.rb
@@ -79,16 +79,21 @@ def determine_package_manager(fallback_manager)
 
     name, version = package_manager.split("@")
 
-    if name == "yarn"
-      raise Error, "a major version must be present for Yarn" if version.nil? || version.empty?
-      return :yarn_classic if version.start_with?("1")
-
-      return :yarn_berry
-    end
+    return determin_yarn_version(version) if name == "yarn"
 
     name.to_sym
   end
 
+  def determin_yarn_version(version)
+    raise Error, "a major version must be present for Yarn" if version.nil? || version.empty?
+
+    # check to see if we're meant to be using Yarn v1 based on the versions major component,
+    # and accounting for the presence of version constraints like ^, ~, and =
+    return :yarn_classic if version.match?(/^[~=^]?1(\.|$)/)
+
+    :yarn_berry
+  end
+
   def new_package_manager(package_manager_name)
     case package_manager_name
     when :npm
diff --git a/spec/package_json_spec.rb b/spec/package_json_spec.rb
@@ -55,15 +55,55 @@
         end
       end
 
-      it "supports yarn classic" do
+      it "supports yarn classic with version 1.2.3" do
         with_package_json_file({ "version" => "1.0.0", "packageManager" => "yarn@1.2.3" }) do
           package_json = described_class.read
 
           expect(package_json.manager).to be_a PackageJson::Managers::YarnClassicLike
         end
       end
 
-      it "supports yarn berry" do
+      it "supports yarn classic with just a major version" do
+        with_package_json_file({ "version" => "1.0.0", "packageManager" => "yarn@1" }) do
+          package_json = described_class.read
+
+          expect(package_json.manager).to be_a PackageJson::Managers::YarnClassicLike
+        end
+      end
+
+      it "supports yarn classic with a caret constraint" do
+        with_package_json_file({ "version" => "1.0.0", "packageManager" => "yarn@^1.2" }) do
+          package_json = described_class.read
+
+          expect(package_json.manager).to be_a PackageJson::Managers::YarnClassicLike
+        end
+      end
+
+      it "supports yarn classic with tilde constraint" do
+        with_package_json_file({ "version" => "1.0.0", "packageManager" => "yarn@~1.2" }) do
+          package_json = described_class.read
+
+          expect(package_json.manager).to be_a PackageJson::Managers::YarnClassicLike
+        end
+      end
+
+      it "supports yarn classic with exact version" do
+        with_package_json_file({ "version" => "1.0.0", "packageManager" => "yarn@=1.2" }) do
+          package_json = described_class.read
+
+          expect(package_json.manager).to be_a PackageJson::Managers::YarnClassicLike
+        end
+      end
+
+      it "does not return yarn classic if the major version is 11" do
+        with_package_json_file({ "version" => "1.0.0", "packageManager" => "yarn@11.2.3" }) do
+          package_json = described_class.read
+
+          expect(package_json.manager).not_to be_a PackageJson::Managers::YarnClassicLike
+        end
+      end
+
+      it "supports yarn berry with version 2.3.2" do
         with_package_json_file({ "version" => "1.0.0", "packageManager" => "yarn@2.3.2" }) do
           package_json = described_class.read
 
