Adds `/regex/` as a regex constructor. A couple of fun points:
1. This makes generic the idea of arbitrary stuff adding a constant.
Both SFunction and LRegex create a statically initialized constant.
Both go through Locals to do this because they LRegex isn't directly
iterable from SScript.
2. Differentiating `/` as-in-division from `/` as-in-start-of-regex
is hard. See:
http://www-archive.mozilla.org/js/language/js20-2002-04/rationale/syntax.html#regular-expressions
The javascript folks have a way, way tougher time of it then we do
because they have semicolon insertion. We have the much simpler
delimiter rules. Even with our simpler life we still have to add
a hack to get lexing `/regex/` to work properly. I chose to add
token-level lookbehind because it seems to be a pretty contained hack.
I considered and rejected lexer modes, a lexer member variable,
having the parser set variables on the lexer (this is a fairly common
solution for js, I believe), and moving regex parsing to the parser
level.
3. I've only added a very small subset of java.util.regex to the
whitelist because it is the subset I needed to test LRegex sanely.
More deserves to be added, and maybe more regex syntax like `=~` and
`==~`. Those can probably be added without too much pain.
This commit fixes a failing lang-painless packaging test after a change
to the dependencies was made in commit
0bfb166eeba0ba8f292550cb9100708c88e4a4c9.
By default the number of searches msearch executes is capped by the number of
nodes multiplied with the default size of the search threadpool. This default can be
overwritten by using the newly added `max_concurrent_searches` parameter.
Before the msearch api would concurrently execute all searches concurrently. If many large
msearch requests would be executed this could lead to some searches being rejected
while other searches in the msearch request would succeed.
The goal of this change is to avoid this exhausting of the search TP.
Closes#17926
Add `}` is statement delimiter but only in places where it is
otherwise a valid part of the syntax, specificall the end of a block.
We do this by matching but not consuming it. Antlr 4 doesn't have
syntax for this so we have to kind of hack it together by actually
matching the `}` and then seeking backwards in the token stream to
"unmatch" it. This looks reasonably efficient. Not perfect, but way
better than the alternatives.
I tried and rejected a few options:
1. Actually consuming the `}` and piping a boolean all through the
grammar from the last statement in a block to the delimiter. This
ended up being a rather large change and made the grammar way more
complicated.
2. Adding a semantic predicate to delimiter that just does the
lookahead. This doesn't work out well because it doesn't work (I
never figured out why) and because it generates an *amazing*
`adaptivePredict` which makes a super huge DFA. It looks super
inefficient.
Closes#18821
Writeable is better for immutable objects like TimeValue.
Switch to writeZLong which takes up less space than the original
writeLong in the majority of cases. Since we expect negative
TimeValues we shouldn't use
writeVLong.
