1 files changed, 58 insertions, 0 deletions
diff --git a/spec/ruby/core/string/strip_spec.rb b/spec/ruby/core/string/strip_spec.rb
new file mode 100644
index 0000000000..81994a7f2e
--- /dev/null
+++ b/spec/ruby/core/string/strip_spec.rb
@@ -0,0 +1,58 @@
+# frozen_string_literal: false
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+require_relative 'shared/strip'
+
+describe "String#strip" do
+  it_behaves_like :string_strip, :strip
+
+  it "returns a new string with leading and trailing whitespace removed" do
+    "   hello   ".strip.should == "hello"
+    "   hello world   ".strip.should == "hello world"
+    "\tgoodbye\r\v\n".strip.should == "goodbye"
+  end
+
+  it "returns a copy of self without leading and trailing NULL bytes and whitespace" do
+    " \x00 goodbye \x00 ".strip.should == "goodbye"
+  end
+end
+
+describe "String#strip!" do
+  it "modifies self in place and returns self" do
+    a = "   hello   "
+    a.strip!.should.equal?(a)
+    a.should == "hello"
+
+    a = "\tgoodbye\r\v\n"
+    a.strip!
+    a.should == "goodbye"
+  end
+
+  it "returns nil if no modifications where made" do
+    a = "hello"
+    a.strip!.should == nil
+    a.should == "hello"
+  end
+
+  it "makes a string empty if it is only whitespace" do
+    "".strip!.should == nil
+    " ".strip.should == ""
+    "  ".strip.should == ""
+  end
+
+  it "removes leading and trailing NULL bytes and whitespace" do
+    a = "\000 goodbye \000"
+    a.strip!
+    a.should == "goodbye"
+  end
+
+  it "raises a FrozenError on a frozen instance that is modified" do
+    -> { "  hello  ".freeze.strip! }.should.raise(FrozenError)
+  end
+
+  # see #1552
+  it "raises a FrozenError on a frozen instance that would not be modified" do
+    -> {"hello".freeze.strip! }.should.raise(FrozenError)
+    -> {"".freeze.strip!      }.should.raise(FrozenError)
+  end
+end