This PR adds support for plugins to the frontend and server.
Implementation-wise, this adds a `plugins` argument to `runFrontend`,
`processHeader`, amd `importModules`, a `plugins` field to
`SetupImportsResult` and `FileSetupResult`. and a `pluginsPath` field to
`LeanPaths`, and then threads the value through these.
Avoids build time overhead until the option is proven to speed up
average projects. Adds Init.Prelude (many tiny declarations, "worst
case") and Init.List.Sublist (many nontrivial theorems, "best case")
under -DElab.async=true as new benchmarks for tracking.
This PR adds core metaprogramming functions for forking off background
tasks from elaboration such that their results are visible to reporting
and the language server
This PR adds support for displaying multiple threads in the trace
profiler output.
`TraceState.tid` needs to be adjusted for this purpose, which is not
done yet by the Lean elaborator as it is still single-threaded.
Between #3106 and this, it was possible that reparsing the file up to
the current position was stuck waiting in the threadpool queue,
displaying a yellow bar and not displaying any info on the unchanged
prefix.
In #4976, I forgot that we do need info trees eventually on the cmdline
for .ilean generation. Unfortunately, not reporting them incrementally
would require an API change, so let's see what the impact of incremental
reporting is
#4976 moved resolution of a promise to an earlier point, but that led to
object being marked MT earlier, so we need to move the code that
minimizes those objects earlier too to revert the performance
regression.
Extends Lean's incremental reporting and reuse between commands into
various steps inside declarations:
* headers and bodies of each (mutual) definition/theorem
* `theorem ... := by` for each contained tactic step, including
recursively inside supported combinators currently consisting of
* `·` (cdot), `case`, `next`
* `induction`, `cases`
* macros such as `next` unfolding to the above

*Incremental reuse* means not recomputing any such steps if they are not
affected by a document change. *Incremental reporting* includes the
parts seen in the recording above: the progress bar and messages. Other
language server features such as hover etc. are *not yet* supported
incrementally, i.e. they are shown only when the declaration has been
fully processed as before.
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Co-authored-by: Scott Morrison <scott.morrison@gmail.com>
As [reported on
Zulip](https://leanprover.zulipchat.com/#narrow/stream/341532-lean4-dev/topic/Find.20references.20broken.20in.20lean.20core/near/437051935).
The `mainModuleName` was being set incorrectly when browsing lean core
sources, resulting in failure of cross-file server requests like "Find
References". Because the `srcSearchPath` is generated asynchronously, we
store it as a `Task Name` which is resolved some time before the header
is finished parsing. (I don't think the `.get` here will ever block,
because the srcSearchPath will be ready by the time the initial command
snap is requested.)
---------
Co-authored-by: Sebastian Ullrich <sebasti@nullri.ch>