nushell/crates/nu-cmd-lang/src/default_context.rs
Ian Manske c747ec75c9
Add command_prelude module (#12291)
# Description
When implementing a `Command`, one must also import all the types
present in the function signatures for `Command`. This makes it so that
we often import the same set of types in each command implementation
file. E.g., something like this:
```rust
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData,
    ShellError, Signature, Span, Type, Value,
};
```

This PR adds the `nu_engine::command_prelude` module which contains the
necessary and commonly used types to implement a `Command`:
```rust
// command_prelude.rs
pub use crate::CallExt;
pub use nu_protocol::{
    ast::{Call, CellPath},
    engine::{Command, EngineState, Stack},
    record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, IntoSpanned,
    PipelineData, Record, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
};
```

This should reduce the boilerplate needed to implement a command and
also gives us a place to track the breadth of the `Command` API. I tried
to be conservative with what went into the prelude modules, since it
might be hard/annoying to remove items from the prelude in the future.
Let me know if something should be included or excluded.
2024-03-26 21:17:30 +00:00

78 lines
1.7 KiB
Rust

use crate::*;
use nu_protocol::engine::{EngineState, StateWorkingSet};
pub fn create_default_context() -> EngineState {
let mut engine_state = EngineState::new();
let delta = {
let mut working_set = StateWorkingSet::new(&engine_state);
macro_rules! bind_command {
( $( $command:expr ),* $(,)? ) => {
$( working_set.add_decl(Box::new($command)); )*
};
}
// Core
bind_command! {
Alias,
Break,
Collect,
Const,
Continue,
Def,
Describe,
Do,
Echo,
ErrorMake,
ExportAlias,
ExportCommand,
ExportConst,
ExportDef,
ExportExtern,
ExportUse,
ExportModule,
Extern,
For,
Hide,
HideEnv,
If,
Ignore,
Overlay,
OverlayUse,
OverlayList,
OverlayNew,
OverlayHide,
LazyMake,
Let,
Loop,
Match,
Module,
Mut,
Return,
Scope,
ScopeAliases,
ScopeCommands,
ScopeEngineStats,
ScopeExterns,
ScopeModules,
ScopeVariables,
Try,
Use,
Version,
While,
};
//#[cfg(feature = "plugin")]
bind_command!(PluginCommand, PluginList, PluginStop, Register,);
working_set.render()
};
if let Err(err) = engine_state.merge_delta(delta) {
eprintln!("Error creating default context: {err:?}");
}
engine_state
}