This allows easy differentiation between ABI incompatible platforms like MSWIN64 and MSVCRT-based MINGW32.
This also implicates a distinct rubygem platform which is also "x64-mingw-ucrt".
Although the term "mingw32" is the OS-part for 64 bit systems as well, the "32" is misleading and confusing for many users.
Therefore the new platform string drops the "32" from the OS part to just "mingw".
This conforms to the common practice of windows platform testing per RUBY_PLATFORM=~/mswin|mingw/ .
Previously the test verified on MSWIN that huge values can not be stored in environment variables but that they can on others.
IMHO the intention of the test should not change between platforms.
Therefore this adjusts the test to have the same intention - that is to store a big value.
This also fixes compatibility with MINGW-UCRT, which previously failed with:
<Errno::EINVAL: Invalid argument - ruby_setenv(foo)>
test/ruby/test_env.rb:512:in `[]='
test/ruby/test_env.rb:512:in `block in test_huge_value'
This fixes issues with paths being loaded twice in certain cases
when symlinks are used.
It took me multiple attempts to get this working. My original
attempt tried to convert paths to realpaths before adding them
to $LOADED_FEATURES. Unfortunately, this doesn't work well
with the loaded feature index, which is based off load paths
and not realpaths. While I was able to get require working, I'm
fairly sure the loaded feature index was not being used as
expected, which would have significant performance implications.
Additionally, I was never able to get that approach working with
autoload when autoloading a non-realpath file. It also broke
some specs.
This takes a more conservative approach. Directly before loading the
file, if the file with the same realpath has been required, the
loading of the file is skipped. The realpaths are stored as
fstrings in a hidden hash.
When rebuilding the loaded feature index, the hash of realpaths
is also rebuilt. I'm guessing this makes rebuilding process
slower, but I don think that is a hot path. In general, modifying
loaded features is only done when reloading, and that tends to be
in non-production environments.
Change test_require_with_loaded_features_pop test to use 30 threads
and 300 iterations, instead of 4 threads and 1000 iterations.
I saw only sporadic failures with 4/1000, but consistent failures
30/300 threads. These failures were due to the fact that the
concurrent deletions from $LOADED_FEATURES in other threads can
result in rb_ary_entry returning nil when rebuilding the loaded
features index.
To avoid concurrency issues when rebuilding the loaded features
index, the building of the index itself is left alone, and
afterwards, a separate loop is done on a copy of the loaded feature
snapshot in order to rebuild the realpaths hash.
Fixes [Bug #17885]
If $LOADED_FEATURES is changed in the just required file, also the
index table needs to be updated before loaded_features_snapshot is
reset. If the snapshot is reset without updating the table, the
name of the added feature will not be found.
Instead of looking for Object::ENV (which can be overwritten),
directly look for the envtbl variable. As that is static in hash.c,
and the lookup code is in process.c, add a couple non-static
functions that will return envtbl (or envtbl#to_hash).
Fixes [Bug #18164]
