This abstracts the base Transport handler to have a MessageHandler
component and allows us to generalize both JSON-RPC 2.0 for MCP (or an
LSP) and DAP format.
This should allow us to create clearly defined clients and servers for
protocols, both for testing and for RPC between the lldb instances and
an lldb-mcp multiplexer.
This basic model is inspiried by the clangd/Transport.h file and the
mlir/lsp-server-support/Transport.h that are both used for LSP servers
within the llvm project.
Additionally, this helps with testing by subclassing `Transport` to
allow us to simplify sending/receiving messages without needing to use a
toJSON/fromJSON and a pair of pipes, see `TestTransport` in
DAP/TestBase.h.
Previously the error only contained the failed to parse JSON message,
which has no additional context.
This improves the error messages and improves the consistency of
handling properties in protocol structures. Updating the fields to use
'ObjectMapper.map' instead of 'ObjectMapper.mapOptional' caught that
adapterID was misspelled as well.
For example, previously:
```
$ echo 'Content-Length: 81\r\n\r\n{"type":"request","command":"initialize","seq":1,"arguments":{"adapterID":12345}} | lldb-dap
```
Worked without an error but now it reports:
```
invalid arguments for request 'initialize': expected string at arguments.adapterID
{
"adapterID": /* error: expected string */ 12345
}
```
Fixes:
```
[6373/7138] Building CXX object tools\lldb\tools\lldb-dap\CMakeFiles\lldb-dap.dir\DAP.cpp.obj
C:\git\llvm-project\lldb\tools\lldb-dap\DAP.cpp(725) : warning C4715: '`lldb_dap::DAP::HandleObject'::`30'::<lambda_2>::operator()': not all control paths return a value
[6421/7138] Building CXX object tools\lldb\tools\lldb-dap\CMakeFiles\lldb-dap.dir\Protocol\ProtocolTypes.cpp.obj
C:\git\llvm-project\lldb\tools\lldb-dap\Protocol\ProtocolTypes.cpp(203) : warning C4715: 'lldb_dap::protocol::ToString': not all control paths return a value
C:\git\llvm-project\lldb\tools\lldb-dap\Protocol\ProtocolTypes.cpp(98) : warning C4715: 'lldb_dap::protocol::toJSON': not all control paths return a value
C:\git\llvm-project\lldb\tools\lldb-dap\Protocol\ProtocolTypes.cpp(72) : warning C4715: 'lldb_dap::protocol::toJSON': not all control paths return a value
C:\git\llvm-project\lldb\tools\lldb-dap\Protocol\ProtocolTypes.cpp(111) : warning C4715: 'lldb_dap::protocol::toJSON': not all control paths return a value
[6426/7138] Building CXX object tools\lldb\tools\lldb-dap\CMakeFiles\lldb-dap.dir\Protocol\ProtocolBase.cpp.obj
C:\git\llvm-project\lldb\tools\lldb-dap\Protocol\ProtocolBase.cpp(287) : warning C4715: 'lldb_dap::protocol::fromJSON': not all control paths return a value
```
Running tests with ubsan enabled showed that the current
`protocol::AdapterFeature` and `protocol::ClientFeature` enums are
incorrectly defined if we want to use them in a `llvm::DenseSet`. The
enums are currently untyped and this results in the undefined behavior.
Adding `FLAGS_ENUM()` wrappers to all the enums in the
`lldb-dap::protocol` namespace to ensure they're typed so they can be
used with types like `llvm::DenseSet`.
This adds new types and helpers to support the 'initialize' request with
the new typed RequestHandler. While working on this I found there were a
few cases where we incorrectly treated initialize arguments as
capabilities. The new `lldb_dap::protocol::InitializeRequestArguments`
and `lldb_dap::protocol::Capabilities` uncovered the inconsistencies.
---------
Co-authored-by: Jonas Devlieghere <jonas@devlieghere.com>
The `DAPError` can be used to craft an error message that is displayed
to a user (with showUser=true).
Any request handler implementation using subclassing `RequestHandler<>`
should be able to use this.
I updated SourceRequestHandler to report DAPError's specifically.
This is a work in progress refactor to add explicit types instead of
generic 'llvm::json::Value' types to the DAP protocol.
This updates RequestHandler to have take the type of the arguments and
response body for serialization for requests.
The 'source' and 'disconnect' request is updated to show how the new
flow
works and includes serialization handling for optional arguments and
'void'
responses.
This is built on top of #130026
---------
Co-authored-by: Adrian Vogelsgesang <adrian.vogelsgesang@tum.de>
