1 files changed, 187 insertions, 0 deletions
diff --git a/spec/ruby/core/warning/warn_spec.rb b/spec/ruby/core/warning/warn_spec.rb
new file mode 100644
index 0000000000..62f36e3454
--- /dev/null
+++ b/spec/ruby/core/warning/warn_spec.rb
@@ -0,0 +1,187 @@
+require_relative '../../spec_helper'
+
+describe "Warning.warn" do
+  it "complains" do
+    -> {
+      Warning.warn("Chunky bacon!")
+    }.should complain("Chunky bacon!")
+  end
+
+  it "does not add a newline" do
+    ruby_exe("Warning.warn('test')", args: "2>&1").should == "test"
+  end
+
+  it "returns nil" do
+    ruby_exe("p Warning.warn('test')", args: "2>&1").should == "testnil\n"
+  end
+
+  it "extends itself" do
+    Warning.singleton_class.ancestors.should.include?(Warning)
+  end
+
+  it "has Warning as the method owner" do
+    ruby_exe("p Warning.method(:warn).owner").should == "Warning\n"
+  end
+
+  it "can be overridden" do
+    code = <<-RUBY
+      $stdout.sync = true
+      $stderr.sync = true
+      def Warning.warn(msg)
+        if msg.start_with?("A")
+          puts msg.upcase
+        else
+          super
+        end
+      end
+      Warning.warn("A warning!")
+      Warning.warn("warning from stderr\n")
+    RUBY
+    ruby_exe(code, args: "2>&1").should == %Q[A WARNING!\nwarning from stderr\n]
+  end
+
+  it "is called by parser warnings" do
+    Warning.should_receive(:warn)
+    verbose = $VERBOSE
+    $VERBOSE = false
+    begin
+      eval "{ key: :value, key: :value2 }"
+    ensure
+      $VERBOSE = verbose
+    end
+  end
+
+  it "is called by Kernel.warn with nil category keyword" do
+    Warning.should_receive(:warn).with("Chunky bacon!\n", category: nil)
+    verbose = $VERBOSE
+    $VERBOSE = false
+    begin
+      Kernel.warn("Chunky bacon!")
+    ensure
+      $VERBOSE = verbose
+    end
+  end
+
+  it "is called by Kernel.warn with given category keyword converted to a symbol" do
+    Warning.should_receive(:warn).with("Chunky bacon!\n", category: :deprecated)
+    verbose = $VERBOSE
+    $VERBOSE = false
+    begin
+      Kernel.warn("Chunky bacon!", category: "deprecated")
+    ensure
+      $VERBOSE = verbose
+    end
+  end
+
+  it "warns when category is :deprecated and Warning[:deprecated] is true" do
+    warn_deprecated = Warning[:deprecated]
+    Warning[:deprecated] = true
+    begin
+      -> {
+        Warning.warn("foo", category: :deprecated)
+      }.should complain("foo")
+    ensure
+      Warning[:deprecated] = warn_deprecated
+    end
+  end
+
+  it "warns when category is :experimental and Warning[:experimental] is true" do
+    warn_experimental = Warning[:experimental]
+    Warning[:experimental] = true
+    begin
+      -> {
+        Warning.warn("foo", category: :experimental)
+      }.should complain("foo")
+    ensure
+      Warning[:experimental] = warn_experimental
+    end
+  end
+
+  ruby_version_is "3.4" do
+    it "warns when category is :strict_unused_block but Warning[:strict_unused_block] is false" do
+      warn_strict_unused_block = Warning[:strict_unused_block]
+      Warning[:strict_unused_block] = true
+      begin
+        -> {
+          Warning.warn("foo", category: :strict_unused_block)
+        }.should complain("foo")
+      ensure
+        Warning[:strict_unused_block] = warn_strict_unused_block
+      end
+    end
+  end
+
+  it "doesn't print message when category is :deprecated but Warning[:deprecated] is false" do
+    warn_deprecated = Warning[:deprecated]
+    Warning[:deprecated] = false
+    begin
+      -> {
+        Warning.warn("foo", category: :deprecated)
+      }.should_not complain
+    ensure
+      Warning[:deprecated] = warn_deprecated
+    end
+  end
+
+  it "doesn't print message when category is :experimental but Warning[:experimental] is false" do
+    warn_experimental = Warning[:experimental]
+    Warning[:experimental] = false
+    begin
+      -> {
+        Warning.warn("foo", category: :experimental)
+      }.should_not complain
+    ensure
+      Warning[:experimental] = warn_experimental
+    end
+  end
+
+  ruby_version_is "3.4" do
+    it "doesn't print message when category is :strict_unused_block but Warning[:strict_unused_block] is false" do
+      warn_strict_unused_block = Warning[:strict_unused_block]
+      Warning[:strict_unused_block] = false
+      begin
+        -> {
+          Warning.warn("foo", category: :strict_unused_block)
+        }.should_not complain
+      ensure
+        Warning[:strict_unused_block] = warn_strict_unused_block
+      end
+    end
+  end
+
+  ruby_bug '#20573', ''...'3.4' do
+    it "isn't called by Kernel.warn when category is :deprecated but Warning[:deprecated] is false" do
+      warn_deprecated = Warning[:deprecated]
+      begin
+        Warning[:deprecated] = false
+        Warning.should_not_receive(:warn)
+        Kernel.warn("foo", category: :deprecated)
+      ensure
+        Warning[:deprecated] = warn_deprecated
+      end
+    end
+
+    it "isn't called by Kernel.warn when category is :experimental but Warning[:experimental] is false" do
+      warn_experimental = Warning[:experimental]
+      begin
+        Warning[:experimental] = false
+        Warning.should_not_receive(:warn)
+        Kernel.warn("foo", category: :experimental)
+      ensure
+        Warning[:experimental] = warn_experimental
+      end
+    end
+  end
+
+  it "prints the message when VERBOSE is false" do
+    -> { Warning.warn("foo") }.should complain("foo")
+  end
+
+  it "prints the message when VERBOSE is nil" do
+    -> { Warning.warn("foo") }.should complain("foo", verbose: nil)
+  end
+
+  it "prints the message when VERBOSE is true" do
+    -> { Warning.warn("foo") }.should complain("foo", verbose: true)
+  end
+end