diff --git a/doc/NEWS-2.6.0 b/doc/NEWS-2.6.0
new file mode 100644
index 0000000000..07e8518841
--- /dev/null
+++ b/doc/NEWS-2.6.0
@@ -0,0 +1,664 @@
+# -*- rdoc -*-
+
+= NEWS for Ruby 2.6.0
+
+This document is a list of user visible feature changes made between
+releases except for bug fixes.
+
+Note that each entry is kept so brief that no reason behind or reference
+information is supplied with. For a full list of changes with all
+sufficient information, see the ChangeLog file or Redmine
+(e.g. https://bugs.ruby-lang.org/issues/$FEATURE_OR_BUG_NUMBER)
+
+== Changes since the 2.5.0 release
+
+=== Language changes
+
+* $SAFE
now is a process global state and can be set to 0 again. [Feature #14250]
+
+* Refinements take place at block passing. [Feature #14223]
+
+* Refinements take place at Kernel#public_send. [Feature #15326]
+
+* Refinements take place at Kernel#respond_to?. [Feature #15327]
+
+* +else+ without +rescue+ now causes a syntax error. [EXPERIMENTAL] [Feature #14606]
+
+* Constant names may start with a non-ASCII capital letter. [Feature #13770]
+
+* Endless ranges are introduced. You can use a Range that has no end,
+ like (0..)
(or similarly (0...)
). [Feature #12912]
+
+ The following shows typical use cases:
+
+ ary[1..] # identical to ary[1..-1]
+ (1...).each {|index| block } # infinite loop from index 1
+ ary.zip(1..) {|elem, index| block } # ary.each.with_index(1) { }
+
+* Non-Symbol keys in a keyword arguments hash cause an exception.
+
+* The "shadowing outer local variable" warning is removed. [Feature #12490]
+
+ You can now write the following without warning:
+
+ user = users.find {|user| cond(user) }
+
+* Print +cause+ of the exception if the exception is not caught and printed
+ its backtraces and error message. [Feature #8257]
+
+* The flip-flop syntax is deprecated. [Feature #5400]
+
+=== Core classes updates (outstanding ones only)
+
+[Array]
+
+ [New methods]
+
+ * Added Array#union and Array#difference instance methods. [Feature #14097]
+
+ [Modified methods]
+
+ * Array#to_h now accepts a block that maps elements to new key/value pairs. [Feature #15143]
+
+ [Aliased methods]
+
+ * Array#filter is a new alias for Array#select. [Feature #13784]
+ * Array#filter! is a new alias for Array#select!. [Feature #13784]
+
+[Binding]
+
+ [New methods]
+
+ * Added Binding#source_location. [Feature #14230]
+
+ This method returns the source location of the binding, a 2-element
+ array of __FILE__
and __LINE__
.
+ Traditionally, the same information could be retrieved by
+ eval("[__FILE__, __LINE__]", binding)
, but we are
+ planning to change this behavior so that Kernel#eval ignores
+ binding's source location [Bug #4352]. So, users should use this
+ newly-introduced method instead of Kernel#eval.
+
+[Dir]
+
+ [New methods]
+
+ * Added Dir#each_child and Dir#children instance methods. [Feature #13969]
+
+[Enumerable]
+
+ [New methods]
+
+ * Enumerable#chain returns an enumerator object that iterates over the
+ elements of the receiver and then those of each argument
+ in sequence. [Feature #15144]
+
+ [Modified methods]
+
+ * Enumerable#to_h now accepts a block that maps elements to new key/value pairs. [Feature #15143]
+
+ [Aliased methods]
+
+ * Enumerable#filter is a new alias for Enumerable#select. [Feature #13784]
+
+[Enumerator::ArithmeticSequence]
+
+ * This is a new class to represent a generator of an arithmetic sequence,
+ that is a number sequence defined by a common difference. It can be used
+ for representing what is similar to Python's slice. You can get an
+ instance of this class from Numeric#step and Range#step.
+
+[Enumerator::Chain]
+
+ * This is a new class to represent a chain of enumerables that works as a
+ single enumerator, generated by such methods as Enumerable#chain and
+ Enumerator#+.
+
+[Enumerator::Lazy]
+
+ [Aliased methods]
+
+ * Enumerator::Lazy#filter is a new alias for
+ Enumerator::Lazy#select. [Feature #13784]
+
+[Enumerator]
+
+ [New methods]
+
+ * Enumerator#+ returns an enumerator object that iterates over the
+ elements of the receiver and then those of the other operand. [Feature #15144]
+
+[ENV]
+
+ [Modified methods]
+
+ * ENV.to_h now accepts a block that maps names and values to new keys and values. [Feature #15143]
+
+[Exception]
+
+ [New options]
+
+ * Exception#full_message takes +:highlight+ and +:order+
+ options. [Bug #14324]
+
+[Hash]
+
+ [Modified methods]
+
+ * Hash#merge, Hash#merge!, and Hash#update now accept multiple
+ arguments. [Feature #15111]
+
+ * Hash#to_h now accepts a block that maps keys and values to new keys and values. [Feature #15143]
+
+ [Aliased methods]
+
+ * Hash#filter is a new alias for Hash#select. [Feature #13784]
+
+ * Hash#filter! is a new alias for Hash#select!. [Feature #13784]
+
+[IO]
+
+ [New options]
+
+ * Added new mode character 'x'
to open files for exclusive
+ access. [Feature #11258]
+
+[Kernel]
+
+ [Aliased methods]
+
+ * Kernel#then is a new alias for Kernel#yield_self. [Feature #14594]
+
+ [New options]
+
+ * Kernel#Complex, Kernel#Float, Kernel#Integer, and
+ Kernel#Rational take an +:exception+ option to specify the way of
+ error handling. [Feature #12732]
+
+ * Kernel#system takes an +:exception+ option to raise an exception
+ on failure. [Feature #14386]
+
+ [Incompatible changes]
+
+ * Kernel#system and Kernel#exec do not close non-standard file descriptors
+ (the default of the +:close_others+ option is changed to +false+,
+ but we still set the +FD_CLOEXEC+ flag on descriptors we
+ create). [Misc #14907]
+
+[KeyError]
+
+ [New options]
+
+ * KeyError.new accepts +:receiver+ and +:key+ options to set receiver and
+ key in Ruby code. [Feature #14313]
+
+[Method]
+
+ [New methods]
+
+ * Added Method#<< and Method#>> for Proc composition. [Feature #6284]
+
+[Module]
+
+ [Modified methods]
+
+ * Module#method_defined?, Module#private_method_defined?, and
+ Module#protected_method_defined? now accept the second
+ parameter as optional. If it is +true+ (the default value), it checks
+ ancestor modules/classes, or checks only the class itself. [Feature #14944]
+
+[NameError]
+
+ [New options]
+
+ * NameError.new accepts a +:receiver+ option to set receiver in Ruby
+ code. [Feature #14313]
+
+[NilClass]
+
+ [New methods]
+
+ * NilClass#=~ is added for compatibility. [Feature #15231]
+
+[NoMethodError]
+
+ [New options]
+
+ * NoMethodError.new accepts a +:receiver+ option to set receiver in Ruby
+ code. [Feature #14313]
+
+[Numeric]
+
+ [Incompatible changes]
+
+ * Numeric#step now returns an instance of the Enumerator::ArithmeticSequence
+ class rather than one of the Enumerator class.
+
+[OpenStruct]
+
+ [Modified methods]
+
+ * OpenStruct#to_h now accepts a block that maps keys and values to new keys and values. [Feature #15143]
+
+[Proc]
+
+ [New methods]
+
+ * Added Proc#<< and Proc#>> for Proc composition. [Feature #6284]
+
+ [Incompatible changes]
+
+ * Proc#call doesn't change $SAFE
any more. [Feature #14250]
+
+[Random]
+
+ [New methods]
+
+ * Added Random.bytes. [Feature #4938]
+
+[Range]
+
+ [New methods]
+
+ * Added Range#% instance method. [Feature #14697]
+
+ [Incompatible changes]
+
+ * Range#=== now uses the +#cover?+ instead of the +#include?+ method. [Feature #14575]
+ * Range#cover? now accepts a Range object. [Feature #14473]
+ * Range#step now returns an instance of the Enumerator::ArithmeticSequence
+ class rather than one of the Enumerator class.
+
+[Regexp/String]
+
+ * Update Unicode version from 10.0.0 to 11.0.0. [Feature #14802]
+
+ This includes a rewrite of the grapheme cluster (/\X/) algorithm
+ and special-casing for Georgian MTAVRULI on String#downcase.
+
+ * Update Emoji version from 5.0 to 11.0.0 [Feature #14802]
+
+[RubyVM::AbstractSyntaxTree]
+
+ [New methods]
+
+ * RubyVM::AbstractSyntaxTree.parse parses a given string and returns AST
+ nodes. [experimental]
+
+ * RubyVM::AbstractSyntaxTree.parse_file parses a given file and returns AST
+ nodes. [experimental]
+
+ * RubyVM::AbstractSyntaxTree.of returns AST nodes of the given proc or method.
+ [experimental]
+
+[RubyVM]
+
+ [New methods]
+
+ * RubyVM.resolve_feature_path identifies the file that will be loaded by
+ "require(feature)". [experimental] [Feature #15230]
+
+[String]
+
+ * String#crypt is now deprecated. [Feature #14915]
+
+ [New features]
+
+ * String#split yields each substring to the block if given. [Feature #4780]
+
+[Struct]
+
+ [Modified methods]
+
+ * Struct#to_h now accepts a block that maps keys and values to new keys and values. [Feature #15143]
+
+ [Aliased method]
+
+ * Struct#filter is a new alias for Struct#select. [Feature #13784]
+
+[Time]
+
+ [New features]
+
+ * Time.new and Time#getlocal accept a timezone object as well as
+ a UTC offset string. Time#+, Time#-, and Time#succ also preserve
+ the timezone. [Feature #14850]
+
+[TracePoint]
+
+ [New features]
+
+ * "script_compiled" event is supported. [Feature #15287]
+
+ [New methods]
+
+ * TracePoint#parameters [Feature #14694]
+
+ * TracePoint#instruction_sequence [Feature #15287]
+
+ * TracePoint#eval_script [Feature #15287]
+
+ [Modified methods]
+
+ * TracePoint#enable accepts new keywords "target:" and "target_line:".
+ [Feature #15289]
+
+=== Stdlib updates (outstanding ones only)
+
+[BigDecimal]
+
+ Update to version 1.4.0. This version includes several compatibility
+ issues, see Compatibility issues section below for details.
+
+ [Modified methods]
+
+ * BigDecimal() accepts the new keyword "exception:" similar to Float().
+
+ [Note for the differences among recent versions]
+
+ You should want to know the differences among recent versions of bigdecimal.
+ Please select the suitable version of bigdecimal according to the following
+ information.
+
+ * 1.3.5 has BigDecimal.new without "exception:" keyword. You can see the
+ deprecation warning of BigDecimal.new when you specify "-w" option.
+ BigDecimal(), BigDecimal.new, and Object#to_d methods are the same.
+
+ * 1.4.0 has BigDecimal.new with "exception:" keyword. You always see the
+ deprecation warning of BigDecimal.new. Object#to_d method is different
+ from BigDecimal() and BigDecimal.new.
+
+ * 2.0.0 will be released soon after releasing Ruby 2.6.0. This version
+ will not have the BigDecimal.new method.
+
+[Bundler]
+
+ * Add Bundler to Standard Library. [Feature #12733]
+
+ * Use 1.17.2, the latest stable version.
+
+[Coverage]
+
+ A oneshot_lines mode is added. [Feature #15022]
+
+ This mode checks "whether each line was executed at least once or not",
+ instead of "how many times each line was executed".
+ A hook for each line is fired at most once, and after it is fired
+ the hook flag is removed, i.e., it runs with zero overhead.
+
+ [New options]
+
+ * Add +:oneshot_lines+ keyword argument to Coverage.start.
+
+ * Add +:stop+ and +:clear+ keyword arguments to Coverage.result.
+ If +clear+ is true, it clears the counters to zero.
+ If +stop+ is true, it disables coverage measurement.
+
+ [New methods]
+
+ * Coverage.line_stub, which is a simple helper function that
+ creates the "stub" of line coverage from a given source code.
+
+[CSV]
+
+ * Upgrade to 3.0.2. This includes performance improvements especially
+ for writing. Writing is about 2 times faster.
+ See https://github.com/ruby/csv/blob/master/NEWS.md.
+
+[ERB]
+
+ [New options]
+
+ * Add +:trim_mode+ and +:eoutvar+ keyword arguments to ERB.new.
+ Now non-keyword arguments other than the first one are softly deprecated
+ and will be removed when Ruby 2.5 becomes EOL. [Feature #14256]
+
+ * erb command's -S option is deprecated, and will be removed
+ in the next version.
+
+[FileUtils]
+
+ [New methods]
+
+ * FileUtils#cp_lr. [Feature #4189]
+
+[Matrix]
+
+ [New methods]
+
+ * Matrix#antisymmetric?, Matrix#skew_symmetric?
+
+ * Matrix#map!, Matrix#collect! [Feature #14151]
+
+ * Matrix#[]=
+
+ * Vector#map!, Vector#collect!
+
+ * Vector#[]=
+
+[Net]
+
+ [New options]
+
+ * Add +:write_timeout+ keyword argument to Net::HTTP.new. [Feature #13396]
+
+ [New methods]
+
+ * Add Net::HTTP#write_timeout and Net::HTTP#write_timeout=. [Feature #13396]
+
+ [New constant]
+
+ * Add Net::HTTPClientException to deprecate Net::HTTPServerException,
+ whose name is misleading. [Bug #14688]
+
+[NKF]
+
+ * Upgrade to nkf v2.1.5
+
+[Psych]
+
+ * Upgrade to Psych 3.1.0
+
+[RDoc]
+
+ * Become about 2 times faster.
+
+ * Use SOURCE_DATE_EPOCH to generate files.
+
+ * Fix method line number that slipped off.
+
+ * Enable --width
, --exclude
,
+ and --line-numbers
that were ignored.
+
+ * Add support for blockquote by ">>>" in default markup notation.
+
+ * Add support for "Raises" lines in TomDoc notation.
+
+ * Fix syntax error output.
+
+ * Fix many parsing bugs.
+
+[REXML]
+
+ * Upgrade to REXML 3.1.9.
+ See https://github.com/ruby/rexml/blob/master/NEWS.md.
+
+ [Improved some XPath implementations]
+
+ * concat()
function: Stringify all arguments before concatenating.
+
+ * string()
function: Support context node.
+
+ * string()
function: Support processing instruction node.
+
+ * Support "*:#{ELEMENT_NAME}"
syntax in XPath 2.0.
+
+ [Fixed some XPath implementations]
+
+ * "//#{ELEMENT_NAME}[#{POSITION}]"
case
+
+ * string()
function: Fix function(document)
+ returns nodes that are out of root elements.
+
+ * "/ #{ELEMENT_NAME} "
case
+
+ * "/ #{ELEMENT_NAME} [ #{PREDICATE} ]"
case
+
+ * "/ #{AXIS}::#{ELEMENT_NAME}"
case
+
+ * "#{N}-#{M}"
case: One or more white spaces were required
+ before "-"
+
+ * "/child::node()"
case
+
+ * "#{FUNCTION}()/#{PATH}"
case
+
+ * "@#{ATTRIBUTE}/parent::"
case
+
+ * "name(#{NODE_SET})"
case
+
+[RSS]
+
+ [New options]
+
+ * RSS::Parser.parse now accepts options as Hash. +:validate+ ,
+ +:ignore_unknown_element+ , +:parser_class+ options are available.
+
+[RubyGems]
+
+ * Upgrade to RubyGems 3.0.1
+
+ * https://blog.rubygems.org/2018/12/19/3.0.0-released.html
+
+ * https://blog.rubygems.org/2018/12/23/3.0.1-released.html
+
+[Set]
+
+ [Aliased methods]
+
+ * Set#filter! is a new alias for Set#select!. [Feature #13784]
+
+[URI]
+
+ [New constant]
+
+ * Add URI::File to handle the file URI scheme. [Feature #14035]
+
+=== Compatibility issues (excluding feature bug fixes)
+
+[Dir]
+
+ * Dir.glob with '\0'
-separated pattern list will be deprecated,
+ and is now warned. [Feature #14643]
+
+[File]
+
+ * File.read, File.binread, File.write, File.binwrite, File.foreach, and
+ File.readlines do not invoke external commands even if the path starts
+ with the pipe character '|'
. [Feature #14245]
+
+[Object]
+
+ * Object#=~ is deprecated. [Feature #15231]
+
+=== Stdlib compatibility issues (excluding feature bug fixes)
+
+* These standard libraries have been promoted to default gems.
+
+ * e2mmap
+ * forwardable
+ * irb
+ * logger
+ * matrix
+ * mutex_m
+ * ostruct
+ * prime
+ * rexml
+ * rss
+ * shell
+ * sync
+ * thwait
+ * tracer
+
+[BigDecimal]
+
+ * The following methods are removed.
+
+ * BigDecimal.allocate
+ * BigDecimal.ver
+
+ * Every BigDecimal object is frozen. [Feature #13984]
+
+ * BigDecimal() parses the given string similar to Float().
+
+ * String#to_d parses the receiver string similar to String#to_f.
+
+ * BigDecimal.new will be removed in version 2.0.
+
+[Pathname]
+
+ * Pathname#read, Pathname#binread, Pathname#write, Pathname#binwrite,
+ Pathname#each_line and Pathname#readlines do not invoke external
+ commands even if the path starts with the pipe character '|'
.
+ This follows [Feature #14245].
+
+=== C API updates
+
+=== Implementation improvements
+
+* Speedup Proc#call because we don't need to care about $SAFE
+ any more. [Feature #14318]
+
+ With +lc_fizzbuzz+ benchmark which uses Proc#call many times we can
+ measure x1.4 improvements. [Bug #10212]
+
+* Speedup block.call where +block+ is passed block parameter. [Feature #14330]
+
+ Ruby 2.5 improves block passing performance. [Feature #14045]
+
+ Additionally, Ruby 2.6 improves the performance of passed block calling.
+
+* Introduce an initial implementation of a JIT (Just-in-time) compiler. [Feature #14235] [experimental]
+
+ * --jit command line option is added to enable JIT. --jit-verbose=1
+ is good for inspection. See ruby --help for others.
+ * To generate machine code, this JIT compiler uses the C compiler used for building
+ the interpreter. Currently GCC, Clang, and Microsoft Visual C++ are supported for it.
+ * --disable-mjit-support option is added to configure. This is added for JIT debugging,
+ but if you get an error on building a header file for JIT, you can use this option to skip
+ building it as a workaround.
+ * rb_waitpid reimplemented on Unix-like platforms to maintain
+ compatibility with processes created for JIT [Bug #14867]
+
+* VM generator script renewal; makes the generated VM more optimized. [GH-1779]
+
+* Thread cache enabled for pthreads platforms (for Thread.new and
+ Thread.start). [Feature #14757]
+
+* timer thread is eliminated for platforms with POSIX timers. [Misc #14937]
+
+* Transient Heap (theap) is supported. [Bug #14858] [Feature #14989]
+
+ theap is a managed heap for short-living memory objects. For example,
+ making a small and short-living Hash object is x2 faster. With rdoc benchmark,
+ we measured 6-7% performance improvement.
+
+* Native implementations (arm32, arm64, ppc64le, win32, win64, x86, amd64) of
+ coroutines to improve performance of Fiber significantly. [Feature #14739]
+
+=== Miscellaneous changes
+
+* On macOS, shared libraries no longer include a full version number of Ruby
+ in their names. This eliminates the burden of each teeny upgrade on the
+ platform that users need to rebuild every extension library.
+
+ [Before]
+ * libruby.2.6.0.dylib
+ * libruby.2.6.dylib -> libruby.2.6.0.dylib
+ * libruby.dylib -> libruby.2.6.0.dylib
+
+ [After]
+ * libruby.2.6.dylib
+ * libruby.dylib -> libruby.2.6.dylib
+
+* Extracted misc/*.el files to https://github.com/ruby/elisp