From c43915a3b7fa43996db3419696c11de090a17561 Mon Sep 17 00:00:00 2001
From: Herwin <herwinw@users.noreply.github.com>
Date: Thu, 31 Aug 2023 18:22:15 +0200
Subject: [PATCH] Add specs for Fiber.scheduler and Fiber.set_scheduler

---
 core/fiber/scheduler_spec.rb     |  8 ++++++
 core/fiber/set_scheduler_spec.rb |  8 ++++++
 core/fiber/shared/scheduler.rb   | 49 ++++++++++++++++++++++++++++++++
 3 files changed, 65 insertions(+)
 create mode 100644 core/fiber/scheduler_spec.rb
 create mode 100644 core/fiber/set_scheduler_spec.rb
 create mode 100644 core/fiber/shared/scheduler.rb

diff --git a/core/fiber/scheduler_spec.rb b/core/fiber/scheduler_spec.rb
new file mode 100644
index 0000000000..15a03c1479
--- /dev/null
+++ b/core/fiber/scheduler_spec.rb
@@ -0,0 +1,8 @@
+require_relative '../../spec_helper'
+require_relative 'shared/scheduler'
+
+require "fiber"
+
+describe "Fiber.scheduler" do
+  it_behaves_like :scheduler, :scheduler
+end
diff --git a/core/fiber/set_scheduler_spec.rb b/core/fiber/set_scheduler_spec.rb
new file mode 100644
index 0000000000..82f6acbe86
--- /dev/null
+++ b/core/fiber/set_scheduler_spec.rb
@@ -0,0 +1,8 @@
+require_relative '../../spec_helper'
+require_relative 'shared/scheduler'
+
+require "fiber"
+
+describe "Fiber.scheduler" do
+  it_behaves_like :scheduler, :set_scheduler
+end
diff --git a/core/fiber/shared/scheduler.rb b/core/fiber/shared/scheduler.rb
new file mode 100644
index 0000000000..2110a5c8b4
--- /dev/null
+++ b/core/fiber/shared/scheduler.rb
@@ -0,0 +1,49 @@
+describe :scheduler, shared: true do
+  it "validates the scheduler for required methods" do
+    required_methods = [:block, :unblock, :kernel_sleep, :io_wait]
+    required_methods.each do |missing_method|
+      scheduler = Object.new
+      required_methods.difference([missing_method]).each do |method|
+        scheduler.define_singleton_method(method) {}
+      end
+      -> { Fiber.set_scheduler(scheduler) }.should raise_error(ArgumentError, /Scheduler must implement ##{missing_method}/)
+    end
+  end
+
+  it "can set and get the scheduler" do
+    required_methods = [:block, :unblock, :kernel_sleep, :io_wait]
+    scheduler = Object.new
+    required_methods.each do |method|
+      scheduler.define_singleton_method(method) {}
+    end
+    Fiber.set_scheduler(scheduler)
+    Fiber.scheduler.should == scheduler
+  end
+
+  it "returns the scheduler after setting it" do
+    required_methods = [:block, :unblock, :kernel_sleep, :io_wait]
+    scheduler = Object.new
+    required_methods.each do |method|
+      scheduler.define_singleton_method(method) {}
+    end
+    result = Fiber.set_scheduler(scheduler)
+    result.should == scheduler
+  end
+
+  it "can remove the scheduler" do
+    required_methods = [:block, :unblock, :kernel_sleep, :io_wait]
+    scheduler = Object.new
+    required_methods.each do |method|
+      scheduler.define_singleton_method(method) {}
+    end
+    Fiber.set_scheduler(scheduler)
+    Fiber.set_scheduler(nil)
+    Fiber.scheduler.should be_nil
+  end
+
+  it "can assign a nil scheduler multiple times" do
+    Fiber.set_scheduler(nil)
+    Fiber.set_scheduler(nil)
+    Fiber.scheduler.should be_nil
+  end
+end