Previously, **{} was removed by the parser:
```
$ ruby --dump=parse -e '{**{}}'
@ NODE_SCOPE (line: 1, location: (1,0)-(1,6))
+- nd_tbl: (empty)
+- nd_args:
| (null node)
+- nd_body:
@ NODE_HASH (line: 1, location: (1,0)-(1,6))*
+- nd_brace: 1 (hash literal)
+- nd_head:
(null node)
```
Since it was removed by the parser, the compiler did not know
about it, and `m(**{})` was therefore treated as `m()`.
This modifies the parser to not remove the `**{}`. A simple
approach for this is fairly simple by just removing a few
lines from the parser, but that would cause two hash
allocations every time it was used. The approach taken here
modifies both the parser and the compiler, and results in `**{}`
not allocating any hashes in the usual case.
The basic idea is we use a literal node in the parser containing
a frozen empty hash literal. In the compiler, we recognize when
that is used, and if it is the only keyword present, we just
push it onto the VM stack (no creation of a new hash or merging
of keywords). If it is the first keyword present, we push a
new empty hash onto the VM stack, so that later keywords can
merge into it. If it is not the first keyword present, we can
ignore it, since the there is no reason to merge an empty hash
into the existing hash.
Example instructions for `m(**{})`
Before (note ARGS_SIMPLE):
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,7)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 opt_send_without_block <callinfo!mid:m, argc:0, FCALL|ARGS_SIMPLE>, <callcache>
0004 leave
```
After (note putobject and KW_SPLAT):
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,7)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 putobject {}
0003 opt_send_without_block <callinfo!mid:m, argc:1, FCALL|KW_SPLAT>, <callcache>
0006 leave
```
Example instructions for `m(**h, **{})`
Before and After (no change):
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,12)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 putspecialobject 1
0003 newhash 0
0005 putself
0006 opt_send_without_block <callinfo!mid:h, argc:0, FCALL|VCALL|ARGS_SIMPLE>, <callcache>
0009 opt_send_without_block <callinfo!mid:core#hash_merge_kwd, argc:2, ARGS_SIMPLE>, <callcache>
0012 opt_send_without_block <callinfo!mid:m, argc:1, FCALL|KW_SPLAT>, <callcache>
0015 leave
```
Example instructions for `m(**{}, **h)`
Before:
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,12)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 putspecialobject 1
0003 newhash 0
0005 putself
0006 opt_send_without_block <callinfo!mid:h, argc:0, FCALL|VCALL|ARGS_SIMPLE>, <callcache>
0009 opt_send_without_block <callinfo!mid:core#hash_merge_kwd, argc:2, ARGS_SIMPLE>, <callcache>
0012 opt_send_without_block <callinfo!mid:m, argc:1, FCALL|KW_SPLAT>, <callcache>
0015 leave
```
After (basically the same except for the addition of swap):
```
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,12)> (catch: FALSE)
0000 putself ( 1)[Li]
0001 newhash 0
0003 putspecialobject 1
0005 swap
0006 putself
0007 opt_send_without_block <callinfo!mid:h, argc:0, FCALL|VCALL|ARGS_SIMPLE>, <callcache>
0010 opt_send_without_block <callinfo!mid:core#hash_merge_kwd, argc:2, ARGS_SIMPLE>, <callcache>
0013 opt_send_without_block <callinfo!mid:m, argc:1, FCALL|KW_SPLAT>, <callcache>
0016 leave
```
for simplicity and consistency.
Now SUPPORT_JOKE needs to be prefixed with OPT_ to make the config
visible in `RubyVM::VmOptsH`, and the inconsistency was introduced.
As it has never been available for override in configure (no #ifndef
guard), it should be fine to rename the config.
This syntax means the method should be treated as a method that
uses keyword arguments, but no specific keyword arguments are
supported, and therefore calling the method with keyword arguments
will raise an ArgumentError. It is still allowed to double splat
an empty hash when calling the method, as that does not pass
any keyword arguments.
After 5e86b005c0, I now think ANYARGS is
dangerous and should be extinct. This commit adds function prototypes
for rb_hash_foreach / st_foreach_safe. Also fixes some prototype
mismatches.
After 5e86b005c0, I now think ANYARGS is
dangerous and should be extinct. This commit deletes ANYARGS from
struct vm_ifunc, but in doing so we also have to decouple the usage
of this struct in compile.c, which (I think) is an abuse of ANYARGS.
Some tooling depends on the current bytecode, and adding an operand
changes the bytecode. While tooling can be updated for new bytecode,
this support doesn't warrant such a change.
This was an intentional bug added in 1.9.
The approach taken here is to add a second operand to the
getconstant instruction for whether nil should be allowed and
treated as current scope.
Fixes [Bug #11718]
Binary dumping the iseq for `case foo in []; end` used to crash as
there was no handling for these exception classes.
Pattern matching generates these classes as operands to `putobject`.
[Bug #16088]
Closes: https://github.com/ruby/ruby/pull/2325
This reverts commit 9faef3113f.
It seemed to cause a failure on macOS Mojave, though I'm unsure how.
20190802T034503Z.fail.html.gz
This tentative revert is to check if the issue is actually caused by the
change or not.
`(ID)1` was assigned to NODE_ARGS#rest_arg for `{|x,| }`.
This change removes the magic number by introducing an explicit macro
variable for it: NODE_SPECIAL_EXCESSED_COMMA.
* internal.h (UNALIGNED_MEMBER_ACCESS, UNALIGNED_MEMBER_PTR):
moved from eval_intern.h.
* compile.c iseq.c, vm.c: use UNALIGNED_MEMBER_PTR for `entries`
in `struct iseq_catch_table`.
* vm_eval.c, vm_insnhelper.c: use UNALIGNED_MEMBER_PTR for `body`
in `rb_method_definition_t`.
