Merge pull request #30 from planningcenter/km/fix/yarn-3-deploying

fix: improve reliability of version comparisons

deploy/lib/deployer/errors.rb

@@ -43,4 +43,7 @@ class FailedToCreatePRError < BaseError
 
   class AutoMergeFailure < BaseError
   end
+
+  class VersionCompareFailure < BaseError
+  end
 end

deploy/lib/deployer/repo/version_compare.rb

@@ -4,9 +4,11 @@ class VersionCompare
       def initialize(
         package_name:,
         version:,
-        current_version: default_current_version
+        current_version: nil,
+        yarn_lock_file_path: "yarn.lock"
       )
         @version = Gem::Version.new(version)
+        @yarn_lock_file_path = yarn_lock_file_path
         @current_version = current_version
         @package_name = package_name
       end
@@ -19,20 +21,32 @@ def major_upgrade?
 
       private
 
-      attr_reader :package_name, :version, :current_version
-
-      def default_current_version
-        @default_current_version ||=
-          begin
-            yarn_lock_file = File.read("yarn.lock")
-            current_version_string =
-              yarn_lock_file.match(
-                /"#{package_name}@[^"]+":\n\s\sversion "([^"]+)"/m
-              )[
-                1
-              ]
-            Gem::Version.new(current_version_string)
-          end
+      attr_reader :package_name, :version, :yarn_lock_file_path
+
+      def current_version
+        @current_version ||= find_current_version
+      end
+
+      def find_current_version
+        match =
+          yarn_lock_file.match(
+            /"#{Regexp.escape(package_name)}@[^"]+":?\n\s+version:?\s"?([^"\n]+)/m
+          )
+        package_not_found if match.nil?
+
+        current_version_string = match[1]
+        Gem::Version.new(current_version_string)
+      end
+
+      def yarn_lock_file
+        @yarn_lock_file ||= File.read(yarn_lock_file_path)
+      rescue Errno::ENOENT
+        raise VersionCompareFailure, "No yarn.lock file found"
+      end
+
+      def package_not_found
+        raise VersionCompareFailure,
+              "Could not find #{package_name} in yarn.lock"
       end
     end
   end

deploy/spec/deployer/repo/version_compare_spec.rb

@@ -0,0 +1,55 @@
+describe Deployer::Repo::VersionCompare do
+  describe "#major_upgrade?" do
+    it "works when detecting a yarn 3 file" do
+      version_compare =
+        described_class.new(
+          package_name: "@planningcenter/tapestry-react",
+          version: "4.6.0",
+          yarn_lock_file_path: "spec/fixtures/yarn3.lock"
+        )
+
+      expect(version_compare.major_upgrade?).to eq(false)
+    end
+
+    it "works when detecting a yarn file" do
+      version_compare =
+        described_class.new(
+          package_name: "@planningcenter/tapestry-react",
+          version: "4.6.0",
+          yarn_lock_file_path: "spec/fixtures/yarn.lock"
+        )
+
+      expect(version_compare.major_upgrade?).to eq(false)
+    end
+
+    it "raises error when lock file does not contain the dependency" do
+      version_compare =
+        described_class.new(
+          package_name: "@planningcenter/tapestry-react",
+          version: "4.6.0",
+          yarn_lock_file_path: "spec/fixtures/empty_lock.lock"
+        )
+
+      expect { version_compare.major_upgrade? }.to raise_error(
+        Deployer::VersionCompareFailure,
+        "[Deployer::VersionCompareFailure]: Could not find @planningcenter/tapestry-react in yarn.lock"
+      )
+    end
+
+    context "when there is no lock file" do
+      it "raises error" do
+        version_compare =
+          described_class.new(
+            package_name: "@planningcenter/tapestry-react",
+            version: "4.6.0",
+            yarn_lock_file_path: "spec/fixtures/missing.lock"
+          )
+
+        expect { version_compare.major_upgrade? }.to raise_error(
+          Deployer::VersionCompareFailure,
+          "[Deployer::VersionCompareFailure]: No yarn.lock file found"
+        )
+      end
+    end
+  end
+end