7 files changed, 205 insertions, 9 deletions

diff --git a/spec/ruby/core/string/shared/codepoints.rb b/spec/ruby/core/string/shared/codepoints.rb
index f71263054a..1c28ba3d5e 100644
--- a/spec/ruby/core/string/shared/codepoints.rb
+++ b/spec/ruby/core/string/shared/codepoints.rb
@@ -1,4 +1,4 @@
-# -*- encoding: binary -*-
+# encoding: binary
 describe :string_codepoints, shared: true do
   it "returns self" do
     s = "foo"
diff --git a/spec/ruby/core/string/shared/dedup.rb b/spec/ruby/core/string/shared/dedup.rb
index 97b5df6ed1..1ffd6aa0fd 100644
--- a/spec/ruby/core/string/shared/dedup.rb
+++ b/spec/ruby/core/string/shared/dedup.rb
@@ -48,9 +48,4 @@ describe :string_dedup, shared: true do
     dynamic.send(@method).should_not equal("this string is frozen".send(@method).freeze)
     dynamic.send(@method).should equal(dynamic)
   end
-
-  it "interns the provided string if it is frozen" do
-    dynamic = "this string is unique and frozen #{rand}".freeze
-    dynamic.send(@method).should equal(dynamic)
-  end
 end
diff --git a/spec/ruby/core/string/shared/each_codepoint_without_block.rb b/spec/ruby/core/string/shared/each_codepoint_without_block.rb
index 31b4c02c9c..c88e5c54c7 100644
--- a/spec/ruby/core/string/shared/each_codepoint_without_block.rb
+++ b/spec/ruby/core/string/shared/each_codepoint_without_block.rb
@@ -1,4 +1,4 @@
-# -*- encoding: binary -*-
+# encoding: binary
 describe :string_each_codepoint_without_block, shared: true do
   describe "when no block is given" do
     it "returns an Enumerator" do
diff --git a/spec/ruby/core/string/shared/encode.rb b/spec/ruby/core/string/shared/encode.rb
index 3776e0d709..9466308886 100644
--- a/spec/ruby/core/string/shared/encode.rb
+++ b/spec/ruby/core/string/shared/encode.rb
@@ -194,6 +194,190 @@ describe :string_encode, shared: true do
     end
   end
 
+  describe "given the fallback option" do
+    context "given a hash" do
+      it "looks up the replacement value from the hash" do
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: { "\ufffd" => "bar" })
+        encoded.should == "Bbar"
+      end
+
+      it "calls to_str on the returned value" do
+        obj = Object.new
+        obj.should_receive(:to_str).and_return("bar")
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: { "\ufffd" => obj })
+        encoded.should == "Bbar"
+      end
+
+      it "does not call to_s on the returned value" do
+        obj = Object.new
+        obj.should_not_receive(:to_s)
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: { "\ufffd" => obj })
+        }.should raise_error(TypeError, "no implicit conversion of Object into String")
+      end
+
+      it "raises an error if the key is not present in the hash" do
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: { "foo" => "bar" })
+        }.should raise_error(Encoding::UndefinedConversionError, "U+FFFD from UTF-8 to US-ASCII")
+      end
+
+      it "raises an error if the value is itself invalid" do
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: { "\ufffd" => "\uffee" })
+        }.should raise_error(ArgumentError, "too big fallback string")
+      end
+
+      it "uses the hash's default value if set" do
+        hash = {}
+        hash.default = "bar"
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: hash)
+        encoded.should == "Bbar"
+      end
+
+      it "uses the result of calling default_proc if set" do
+        hash = {}
+        hash.default_proc = -> _, _ { "bar" }
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: hash)
+        encoded.should == "Bbar"
+      end
+    end
+
+    context "given an object inheriting from Hash" do
+      before do
+        klass = Class.new(Hash)
+        @hash_like = klass.new
+        @hash_like["\ufffd"] = "bar"
+      end
+
+      it "looks up the replacement value from the object" do
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: @hash_like)
+        encoded.should == "Bbar"
+      end
+    end
+
+    context "given an object responding to []" do
+      before do
+        klass = Class.new do
+          def [](c) = c.bytes.inspect
+        end
+        @hash_like = klass.new
+      end
+
+      it "calls [] on the object, passing the invalid character" do
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: @hash_like)
+        encoded.should == "B[239, 191, 189]"
+      end
+    end
+
+    context "given an object not responding to []" do
+      before do
+        @non_hash_like = Object.new
+      end
+
+      it "raises an error" do
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: @non_hash_like)
+        }.should raise_error(Encoding::UndefinedConversionError, "U+FFFD from UTF-8 to US-ASCII")
+      end
+    end
+
+    context "given a proc" do
+      it "calls the proc to get the replacement value, passing in the invalid character" do
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: proc { |c| c.bytes.inspect })
+        encoded.should == "B[239, 191, 189]"
+      end
+
+      it "calls to_str on the returned value" do
+        obj = Object.new
+        obj.should_receive(:to_str).and_return("bar")
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: proc { |c| obj })
+        encoded.should == "Bbar"
+      end
+
+      it "does not call to_s on the returned value" do
+        obj = Object.new
+        obj.should_not_receive(:to_s)
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: proc { |c| obj })
+        }.should raise_error(TypeError, "no implicit conversion of Object into String")
+      end
+
+      it "raises an error if the returned value is itself invalid" do
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: -> c { "\uffee" })
+        }.should raise_error(ArgumentError, "too big fallback string")
+      end
+    end
+
+    context "given a lambda" do
+      it "calls the lambda to get the replacement value, passing in the invalid character" do
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: -> c { c.bytes.inspect })
+        encoded.should == "B[239, 191, 189]"
+      end
+
+      it "calls to_str on the returned value" do
+        obj = Object.new
+        obj.should_receive(:to_str).and_return("bar")
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: -> c { obj })
+        encoded.should == "Bbar"
+      end
+
+      it "does not call to_s on the returned value" do
+        obj = Object.new
+        obj.should_not_receive(:to_s)
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: -> c { obj })
+        }.should raise_error(TypeError, "no implicit conversion of Object into String")
+      end
+
+      it "raises an error if the returned value is itself invalid" do
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: -> c { "\uffee" })
+        }.should raise_error(ArgumentError, "too big fallback string")
+      end
+    end
+
+    context "given a method" do
+      def replace(c) = c.bytes.inspect
+      def replace_bad(c) = "\uffee"
+
+      def replace_to_str(c)
+        obj = Object.new
+        obj.should_receive(:to_str).and_return("bar")
+        obj
+      end
+
+      def replace_to_s(c)
+        obj = Object.new
+        obj.should_not_receive(:to_s)
+        obj
+      end
+
+      it "calls the method to get the replacement value, passing in the invalid character" do
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: method(:replace))
+        encoded.should == "B[239, 191, 189]"
+      end
+
+      it "calls to_str on the returned value" do
+        encoded = "B\ufffd".encode(Encoding::US_ASCII, fallback: method(:replace_to_str))
+        encoded.should == "Bbar"
+      end
+
+      it "does not call to_s on the returned value" do
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: method(:replace_to_s))
+        }.should raise_error(TypeError, "no implicit conversion of Object into String")
+      end
+
+      it "raises an error if the returned value is itself invalid" do
+        -> {
+          "B\ufffd".encode(Encoding::US_ASCII, fallback: method(:replace_bad))
+        }.should raise_error(ArgumentError, "too big fallback string")
+      end
+    end
+  end
+
   describe "given the xml: :text option" do
     it "replaces all instances of '&' with '&'" do
       '& and &'.send(@method, "UTF-8", xml: :text).should == '& and &'
diff --git a/spec/ruby/core/string/shared/eql.rb b/spec/ruby/core/string/shared/eql.rb
index 845b0a3e15..d5af337d53 100644
--- a/spec/ruby/core/string/shared/eql.rb
+++ b/spec/ruby/core/string/shared/eql.rb
@@ -1,4 +1,4 @@
-# -*- encoding: binary -*-
+# encoding: binary
 require_relative '../../../spec_helper'
 require_relative '../fixtures/classes'
 
diff --git a/spec/ruby/core/string/shared/slice.rb b/spec/ruby/core/string/shared/slice.rb
index 2f69b9ddce..7b9b9f6a14 100644
--- a/spec/ruby/core/string/shared/slice.rb
+++ b/spec/ruby/core/string/shared/slice.rb
@@ -119,6 +119,18 @@ describe :string_slice_index_length, shared: true do
     "hello there".send(@method, -4,-3).should == nil
   end
 
+  platform_is pointer_size: 64 do
+    it "returns nil if the length is negative big value" do
+      "hello there".send(@method, 4, -(1 << 31)).should == nil
+
+      # by some reason length < -(1 << 31) on CI on Windows leads to
+      # 'RangeError: bignum too big to convert into `long'' error
+      platform_is_not :windows do
+        "hello there".send(@method, 4, -(1 << 63)).should == nil
+      end
+    end
+  end
+
   it "calls to_int on the given index and the given length" do
     "hello".send(@method, 0.5, 1).should == "h"
     "hello".send(@method, 0.5, 2.5).should == "he"
@@ -152,6 +164,11 @@ describe :string_slice_index_length, shared: true do
     -> { "hello".send(@method, 0, bignum_value) }.should raise_error(RangeError)
   end
 
+  it "raises a RangeError if the index or length is too small" do
+    -> { "hello".send(@method, -bignum_value, 1) }.should raise_error(RangeError)
+    -> { "hello".send(@method, 0, -bignum_value) }.should raise_error(RangeError)
+  end
+
   it "returns String instances" do
     s = StringSpecs::MyString.new("hello")
     s.send(@method, 0,0).should be_an_instance_of(String)
diff --git a/spec/ruby/core/string/shared/succ.rb b/spec/ruby/core/string/shared/succ.rb
index b69a394875..7c68345f10 100644
--- a/spec/ruby/core/string/shared/succ.rb
+++ b/spec/ruby/core/string/shared/succ.rb
@@ -1,4 +1,4 @@
-# -*- encoding: binary -*-
+# encoding: binary
 describe :string_succ, shared: true do
   it "returns an empty string for empty strings" do
     "".send(@method).should == ""