This is a follow up for 3f9562015e.
Before this commit, it was possible to create a shared string which
shares with another shared string by passing a frozen shared string
to `str_duplicate`.
Such string looks like:
```
-------- -----------------
| root | ------ owns -----> | root's buffer |
-------- -----------------
^ ^ ^
----------- | |
| shared1 | ------ references ----- |
----------- |
^ |
----------- |
| shared2 | ------ references ---------
-----------
```
This is bad news because `rb_fstring(shared2)` can make `shared1`
independent, which severs the reference from `shared1` to `root`:
```c
/* from fstr_update_callback() */
str = str_new_frozen(rb_cString, shared2); /* can return shared1 */
if (STR_SHARED_P(str)) { /* shared1 is also a shared string */
str_make_independent(str); /* no frozen check */
}
```
If `shared1` was the only reference to `root`, then `root` can be
reclaimed by the GC, leaving `shared2` in a corrupted state:
```
----------- --------------------
| shared1 | -------- owns --------> | shared1's buffer |
----------- --------------------
^
|
----------- -------------------------
| shared2 | ------ references ----> | root's buffer (freed) |
----------- -------------------------
```
Here is a reproduction script for the situation this commit fixes.
```ruby
a = ('a' * 24).strip.freeze.strip
-a
p a
4.times { GC.start }
p a
```
- string.c (str_duplicate): always share with the root string when
the original is a shared string.
- test_rb_str_dup.rb: specifically test `rb_str_dup` to make
sure it does not try to share with a shared string.
[Bug #15792]
Closes: https://github.com/ruby/ruby/pull/2159
This allows cases such as:
```ruby
m ->(a = ->{@1}) {a}
m.call.call(1)
m2 ->(a: ->{@1}) {a}
m2.call.call(2)
```
Previously, this would cause a syntax error.
[Bug#15789]
Because `proc{|| @1}` is a syntax error, the following should
also be syntax errors:
```ruby
proc { |
| @1}
```
```ruby
proc { |; a| @1 }
```
This fixes both cases.
[Bug #15825]
* lib/reine.rb, lib/reline/*: Reline is a readline stdlib compatible
library.
* lib/readline.rb: Readline uses a fallback to Reline when ext/readline
doesn't exist.
* tool/sync_default_gems.rb: add ruby/reline as a default gem.
* appveyor.yml: add "set RELINE_TEST_ENCODING=Windows-31J" for test suit
of Reline, and add "--exclude readline" to "nmake test-all" on Visual
Studio builds because of strange behavior.
* spec/ruby/library/readline/spec_helper.rb: skip Reline as with
RbReadline.
* parse.y (heredoc_identifier): CR in here-document identifier
might or might not result in a syntax error, by the EOL code.
make a syntax error regardless of the EOL code.
* parse.y (heredoc_identifier): quoted here-document identifier
must end within the same line.
the only corner case that here-document identifier can contain a
newline is that the closing qoute is placed at the beginning of
the next line, and has been warned since 2.4.
```ruby
<<"EOS
" # warning: here document identifier ends with a newline
EOS
```
This string can include elements that were not in either string
passed to File.realpath, even if one of the strings is an
absolute path, due to symlinks:
```ruby
Dir.mkdir('b') unless File.directory?('b')
File.write('b/a', '') unless File.file?('b/a')
File.symlink('b', 'c') unless File.symlink?('c')
path = File.realpath('c/a'.untaint, Dir.pwd.untaint)
path # "/home/testr/ruby/b/a"
path.tainted? # should be true, as 'b' comes from file system
```
[Bug #15803]
from 89e9add06d.
This adds syntax highlight support for Module on inspect.
In addition to that, I'm adding a trailing space in test_color.rb for
testing ruby-commit-hook's auto-style.
* string.c (str_duplicate): share the root shared string if the
original string is already sharing, so that all shared strings
refer the root shared string directly. indirect sharing can
cause a dangling pointer.
[Bug #15792]
* parse.y (internal_id): number the ID serial for internal use by
counting down from the neary maximum value, not to accidentally
match permanent IDs.
[Bug #15768]
For example when an array containing objects is a hash key, the contents
of the array may move which can cause the hash value for the array to
change. This commit makes the default `hash` value based off the
object id, so the hash value will remain stable.
Fixes test/shell/test_command_processor.rb
Alan Wu
NARUSE, Yui
Takashi Kokubun
Jean Boussier
Jeremy Evans
Nobuyoshi Nakada
Masatoshi SEKI
NAKAMURA Usaku
manga_osyo
aycabta
Yusuke Endoh
David Rodríguez
git
naruse
Kazuhiro NISHIYAMA
Aaron Patterson
Seiei Miyagi