This PR adds support for code actions that resolve 'unknown identifier'
errors by either importing the missing declaration or by changing the
identifier to one from the environment.
<details>
<summary>Demo (Click to open)</summary>

</details>
Specifically, the following kinds of code actions are added by this PR,
all of which are triggered on 'unknown identifier' errors:
- A code action to import the module containing the identifier at the
text cursor position.
- A code action to change the identifier at the text cursor position to
one from the environment.
- A source action to import the modules for all unambiguous identifiers
in the file.
### Details
When clicking on an identifier with an 'unknown identifier' diagnostic,
after a debounce delay of 1000ms, the language server looks up the
(potentially partial) identifier at the position of the cursor in the
global reference data structure by fuzzy-matching against all
identifiers and collects the 10 closest matching entries. This search
accounts for open namespaces at the position of the cursor, including
the namespace of the type / expected type when using dot notation. The
10 closest matching entries are then offered to the user as code
actions:
- If the suggested identifier is not contained in the environment, a
code action that imports the module that the identifier is contained in
and changes the identifier to the suggested one is offered. The
suggestion is inserted in a "minimal" manner, i.e. by accounting for
open namespaces.
- If the suggested identifier is contained in the environment, a code
action that only changes the identifier to the suggested one is offered.
- If the suggested identifier is not contained in the environment and
the suggested identifier is a perfectly unambiguous match, a source
action to import all unambiguous in the file is offered.
The source action to import all unambiguous identifiers can also always
be triggered by right-clicking in the document and selecting the 'Source
Action...' entry.
At the moment, for large projects, the search for closely matching
identifiers in the global reference data structure is still a bit slow.
I hope to optimize it next quarter.
### Implementation notes
- Since the global reference data structure is in the watchdog process,
whereas the elaboration information is in the file worker process, this
PR implements support for file worker -> watchdog requests, including a
new `$/lean/queryModule` request that can be used by the file worker to
request global identifier information.
- To identify 'unknown identifier' errors, several 'unknown identifier'
errors in the elaborator are tagged with a new tag.
- The debounce delay of 1000ms is necessary because VS Code will
re-request code actions while editing an unknown identifier and also
while hovering over the identifier.
- We also implement cancellation for these 'unknown identifier' code
actions. Once the file worker responds to the request as having been
cancelled, the watchdog cancels its computation of all corresponding
file worker -> watchdog requests, too.
- Aliases (i.e. `export`) are currently not accounted for. I've found
that we currently don't handle them correctly in auto-completion, too,
so we will likely add support for this later when fixing the
corresponding auto-completion issue.
- The new code actions added by this request support incrementality.
This PR splits the environment used by the kernel from that used by the
elaborator, providing the foundation for tracking of asynchronously
elaborated declarations, which will exist as a concept only in the
latter.
Minor changes:
* kernel diagnostics are moved from an environment extension to a direct
environment as they are the only extension used directly by the kernel
* `initQuot` is moved from an environment header field to a direct
environment as it is the only header field used by the kernel; this also
makes the remaining header immutable after import
Makes `MessageData.ofConstName` available without needing to import the
pretty printer. Any code making use of `MessageData` can write `m!" ...
{.ofConstName n} ... "` to have the name print with hover information.
More error messages now have hover information.
* Now `.ofConstName` also has a boolean flag to make names print fully
qualified. Default: false.
* Now `.ofConstName` will sanitize names that aren't constants. It is OK
to use it in `"unknown constant '{.ofConstName constName}'"` errors.
Usability note: it is more user-friendly to have "has already been
declared" errors report the fully qualified name. For this, write
`m!"{.ofConstName n true} has already been declared"`.
Fixes#5565, by using tags instead of trying to string match on a
`MessageData`. This ends up reverting some unwanted test output changes
from #4781 too.
This changes `isMaxRecDepth` for good measure too.
This was a regression in Lean 4.11.0, so may be worth backporting to
4.12.x, if not also 4.11.x.
luckily the necessary functionality already exists in the form of
`addPPExplicitToExposeDiff`. But it is not cheap, and we should not run
this code
when the error message isn’t shown, so we should do this lazily.
We already had `MessageData.ofPPFormat` to assemble the error message
lazily, but it
was restricted to returning `FormatWithInfo`, a data type that doesn’t
admit a nice
API to compose more complex messages (like `Format` or `MessageData`
has; an attempt to
fix that is in #3926).
Therefore we split the functionality of `.ofPPFormat` into
`.ofFormatWithInfo` and `.ofLazy`,
and use `.ofLazy` to compute the more complex error message of `apply`.
Fixes#3232.
---------
Co-authored-by: David Thrane Christiansen <david@davidchristiansen.dk>
Co-authored-by: Wojciech Nawrocki <wjnawrocki@protonmail.com>
@Kha I marked the corresponding methods as `protected`.
I currently can't stand `throw_error`, and I am optimistic about
server highlighting feature you are working on :)
@Kha I was tired of writing `arbitrary _` :)
There 0 places in the stdlib where the type needs to be provided.
If in the future we need to specify the type we can use
`arbitrary (α := <type>)`
`MacroM` will implement `MonadRef` because
1- It will be easier to throw errors from macros
2- We will be able to `getRef` to retrieve the syntax node at macro
rules.
I renamed `Ref` to `MonadRef` to make it consistent with other classes
providing monadic methods (e.g. `MonadEnv`, `MonadState`, etc).
cc @Kha
@Kha: the new `ST` (and `EST`) are escapable like the Haskell ST monad.
It makes `StateRefT` much more useful because we can now run it from pure
code.