1 files changed, 117 insertions, 0 deletions
diff --git a/spec/ruby/core/string/center_spec.rb b/spec/ruby/core/string/center_spec.rb
new file mode 100644
index 0000000000..ac5b8a2ff3
--- /dev/null
+++ b/spec/ruby/core/string/center_spec.rb
@@ -0,0 +1,117 @@
+# -*- encoding: utf-8 -*-
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+
+describe "String#center with length, padding" do
+  it "returns a new string of specified length with self centered and padded with padstr" do
+    "one".center(9, '.').should == "...one..."
+    "hello".center(20, '123').should == "1231231hello12312312"
+    "middle".center(13, '-').should == "---middle----"
+
+    "".center(1, "abcd").should == "a"
+    "".center(2, "abcd").should == "aa"
+    "".center(3, "abcd").should == "aab"
+    "".center(4, "abcd").should == "abab"
+    "".center(6, "xy").should == "xyxxyx"
+    "".center(11, "12345").should == "12345123451"
+
+    "|".center(2, "abcd").should == "|a"
+    "|".center(3, "abcd").should == "a|a"
+    "|".center(4, "abcd").should == "a|ab"
+    "|".center(5, "abcd").should == "ab|ab"
+    "|".center(6, "xy").should == "xy|xyx"
+    "|".center(7, "xy").should == "xyx|xyx"
+    "|".center(11, "12345").should == "12345|12345"
+    "|".center(12, "12345").should == "12345|123451"
+
+    "||".center(3, "abcd").should == "||a"
+    "||".center(4, "abcd").should == "a||a"
+    "||".center(5, "abcd").should == "a||ab"
+    "||".center(6, "abcd").should == "ab||ab"
+    "||".center(8, "xy").should == "xyx||xyx"
+    "||".center(12, "12345").should == "12345||12345"
+    "||".center(13, "12345").should == "12345||123451"
+  end
+
+  it "pads with whitespace if no padstr is given" do
+    "two".center(5).should == " two "
+    "hello".center(20).should == "       hello        "
+  end
+
+  it "returns self if it's longer than or as long as the specified length" do
+    "".center(0).should == ""
+    "".center(-1).should == ""
+    "hello".center(4).should == "hello"
+    "hello".center(-1).should == "hello"
+    "this".center(3).should == "this"
+    "radiology".center(8, '-').should == "radiology"
+  end
+
+  it "calls #to_int to convert length to an integer" do
+    "_".center(3.8, "^").should == "^_^"
+
+    obj = mock('3')
+    obj.should_receive(:to_int).and_return(3)
+
+    "_".center(obj, "o").should == "o_o"
+  end
+
+  it "raises a TypeError when length can't be converted to an integer" do
+    -> { "hello".center("x")       }.should.raise(TypeError)
+    -> { "hello".center("x", "y")  }.should.raise(TypeError)
+    -> { "hello".center([])        }.should.raise(TypeError)
+    -> { "hello".center(mock('x')) }.should.raise(TypeError)
+  end
+
+  it "calls #to_str to convert padstr to a String" do
+    padstr = mock('123')
+    padstr.should_receive(:to_str).and_return("123")
+
+    "hello".center(20, padstr).should == "1231231hello12312312"
+  end
+
+  it "raises a TypeError when padstr can't be converted to a string" do
+    -> { "hello".center(20, 100)       }.should.raise(TypeError)
+    -> { "hello".center(20, [])      }.should.raise(TypeError)
+    -> { "hello".center(20, mock('x')) }.should.raise(TypeError)
+  end
+
+  it "raises an ArgumentError if padstr is empty" do
+    -> { "hello".center(10, "") }.should.raise(ArgumentError)
+    -> { "hello".center(0, "")  }.should.raise(ArgumentError)
+  end
+
+  it "returns String instances when called on subclasses" do
+    StringSpecs::MyString.new("").center(10).should.instance_of?(String)
+    StringSpecs::MyString.new("foo").center(10).should.instance_of?(String)
+    StringSpecs::MyString.new("foo").center(10, StringSpecs::MyString.new("x")).should.instance_of?(String)
+
+    "".center(10, StringSpecs::MyString.new("x")).should.instance_of?(String)
+    "foo".center(10, StringSpecs::MyString.new("x")).should.instance_of?(String)
+  end
+
+  describe "with width" do
+    it "returns a String in the same encoding as the original" do
+      str = "abc".dup.force_encoding Encoding::IBM437
+      result = str.center 6
+      result.should == " abc  "
+      result.encoding.should.equal?(Encoding::IBM437)
+    end
+  end
+
+  describe "with width, pattern" do
+    it "returns a String in the compatible encoding" do
+      str = "abc".dup.force_encoding Encoding::IBM437
+      result = str.center 6, "あ"
+      result.should == "あabcああ"
+      result.encoding.should.equal?(Encoding::UTF_8)
+    end
+
+    it "raises an Encoding::CompatibilityError if the encodings are incompatible" do
+      pat = "ア".encode Encoding::EUC_JP
+      -> do
+        "あれ".center 5, pat
+      end.should.raise(Encoding::CompatibilityError)
+    end
+  end
+end