From 3130c704afa0a163395bbf5279b69d8da42a5b8d Mon Sep 17 00:00:00 2001
From: Jakob Skjerning <jakob@mentalized.net>
Date: Mon, 8 Dec 2025 14:38:52 +0100
Subject: [PATCH 1/3] Make it possible to run the test in isolation

Without this we'd get

```
$ ruby -Itest test/classlist/test_operation.rb
Run options: --seed 53158

..EE........E...

Finished in 0.010779s, 1391.5948 runs/s, 1298.8218 assertions/s.

  1) Error:
TestClasslistOperation#test_all_the_operations:
NameError: uninitialized constant Classlist::Reset
    test/classlist/test_operation.rb:97:in 'TestClasslistOperation#test_all_the_operations'

  2) Error:
TestClasslistOperation#test_reset_as_manual_operations:
NameError: uninitialized constant Classlist::Reset
    test/classlist/test_operation.rb:41:in 'TestClasslistOperation#test_reset_as_manual_operations'

  3) Error:
TestClasslistOperation#test_reset:
NameError: uninitialized constant Classlist::Reset
    test/classlist/test_operation.rb:35:in 'TestClasslistOperation#test_reset'
```
---
 test/classlist/test_operation.rb | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/classlist/test_operation.rb b/test/classlist/test_operation.rb
index 546bb86..21970f4 100644
--- a/test/classlist/test_operation.rb
+++ b/test/classlist/test_operation.rb
@@ -4,6 +4,7 @@
 
 require "classlist/add"
 require "classlist/remove"
+require "classlist/reset"
 
 class TestClasslistOperation < Minitest::Test
   def test_add

From 3892e86c5fc5345ab408035dae6c4236839742b0 Mon Sep 17 00:00:00 2001
From: Jakob Skjerning <jakob@mentalized.net>
Date: Mon, 8 Dec 2025 15:11:13 +0100
Subject: [PATCH 2/3] Assume adding a Classlist is an Add operation

Ie doing

  Classlist.new("a b c") + Classlist.new("d e")

is the same as

  Classlist.new("a b c") + Classlist::Add.new("d e")

and most notably doing

  Classlist.new("a") + Classlist::Remove.new("a") + Classlist.new("b")

is the same as

  Classlist.new("a") + Classlist::Remove.new("a") + Classlist::Add.new("b")

which it wasn't before.

Adding a "base" Classlist in that manner would merge it into the Remove
operation, effectively turning the statement into

  Classlist.new("a") + Classlist::Remove.new("a b")

which is not the intended behavior
---
 CHANGELOG.md                     |  4 ++++
 lib/classlist.rb                 |  5 +++++
 test/classlist/test_operation.rb | 16 ++++++++++++++++
 3 files changed, 25 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e9ef493..655b067 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Code of Conduct.
 - Add support for Ruby 3.2 and 3.3 (no changes).
 
+### Fixed
+
+- Adding a raw `Classlist` to a set of `Classlist::Operation`s would merge the `Classlist` into the last operation, instead of treating the `Classlist` as an implicit `Classlist::Add` operation (which it should be).
+
 ## [1.1.0] - 2022-11-07
 
 ### Added
diff --git a/lib/classlist.rb b/lib/classlist.rb
index d2428f5..ffc23d2 100644
--- a/lib/classlist.rb
+++ b/lib/classlist.rb
@@ -16,6 +16,11 @@ class Error < StandardError; end
 
   # Returns the Classlist resulting from adding other to this classlist.
   def +(other)
+    # When adding a basic Classlist to an existing list, assume an Add operation
+    if other.is_a?(Classlist) && !other.is_a?(Classlist::Operation)
+      other = Classlist::Add.new(other.entries.dup)
+    end
+
     case other
     when Classlist::Operation
       add_operation(other)
diff --git a/test/classlist/test_operation.rb b/test/classlist/test_operation.rb
index 21970f4..a57152b 100644
--- a/test/classlist/test_operation.rb
+++ b/test/classlist/test_operation.rb
@@ -93,6 +93,22 @@ def test_storing_operations_in_a_variable
     assert_equal(["this"], result.to_a)
   end
 
+  def test_adding_after_removing
+    base = Classlist.new("foo")
+    removal = Classlist::Remove.new("foo")
+    addition = Classlist::Add.new("addition")
+    result = base + removal + addition
+    assert_equal(["addition"], result.to_a)
+  end
+
+  def test_adding_a_classlist_instance_assumes_add
+    base = Classlist.new("foo")
+    removal = Classlist::Remove.new("foo")
+    addition = Classlist.new("addition")
+    result = base + removal + addition
+    assert_equal(["addition"], result.to_a)
+  end
+
   def test_all_the_operations
     result = Classlist.new("start") +
       Classlist::Reset.new("with") +

From 2e6610076a0e1f68e6e537b5f784c95f29fc17a1 Mon Sep 17 00:00:00 2001
From: Jakob Skjerning <jakob@mentalized.net>
Date: Mon, 8 Dec 2025 15:15:52 +0100
Subject: [PATCH 3/3] Appease standard

>   lib/classlist.rb:12:3: Layout/EmptyLinesAfterModuleInclusion: Add an
>   empty line after module inclusion.
---
 lib/classlist.rb | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/classlist.rb b/lib/classlist.rb
index ffc23d2..dedc0c4 100644
--- a/lib/classlist.rb
+++ b/lib/classlist.rb
@@ -10,6 +10,7 @@ class ArgumentError < ::ArgumentError; end
   class Error < StandardError; end
 
   extend Forwardable
+
   def_delegators :@entries, :each
 
   attr_reader :entries, :operations