62 lines
2.2 KiB
Rust
62 lines
2.2 KiB
Rust
use rlua::{Context, MetaMethod, RegistryKey, Table, UserData, UserDataMethods, Value};
|
||
use std::collections::HashMap;
|
||
|
||
use crate::types::Result;
|
||
|
||
/// Stores Lua modules indexed by module name, and provides an
|
||
/// `rlua::MetaMethod` to enable `require`ing the stored modules by name
|
||
/// in an `rlua::Context`.
|
||
struct Searcher {
|
||
/// A `HashMap` of Lua modules in `String` representation, indexed
|
||
/// by module name.
|
||
modules: HashMap<String, String>,
|
||
|
||
/// An `rlua::RegistryKey` whose value is the Lua environment within
|
||
/// which the user made the request to instantiate a `Searcher` for
|
||
/// `modules`.
|
||
globals: RegistryKey,
|
||
}
|
||
|
||
impl Searcher {
|
||
fn new(modules: HashMap<String, String>, globals: RegistryKey) -> Self {
|
||
Self { modules, globals }
|
||
}
|
||
}
|
||
|
||
impl UserData for Searcher {
|
||
fn add_methods<'lua, M: UserDataMethods<'lua, Self>>(methods: &mut M) {
|
||
methods.add_meta_method(MetaMethod::Call, |lua_ctx, this, name: String| {
|
||
match this.modules.get(&name) {
|
||
Some(content) => Ok(Value::Function(
|
||
lua_ctx
|
||
.load(content)
|
||
.set_name(&name)?
|
||
.set_environment(lua_ctx.registry_value::<Table>(&this.globals)?)?
|
||
.into_function()?,
|
||
)),
|
||
None => Ok(Value::Nil),
|
||
}
|
||
});
|
||
}
|
||
}
|
||
|
||
/// Extend `rlua::Context` to support `require`ing Lua modules by name.
|
||
pub trait AddSearcher<'a> {
|
||
/// Add a `HashMap` of Lua modules indexed by module name to Lua’s
|
||
/// `package.searchers` table in an `rlua::Context`, with lookup
|
||
/// functionality provided by the `rlua_searcher::Searcher` struct.
|
||
fn add_searcher(&self, modules: HashMap<String, String>) -> Result<()>;
|
||
}
|
||
|
||
impl<'a> AddSearcher<'a> for Context<'a> {
|
||
fn add_searcher(&self, modules: HashMap<String, String>) -> Result<()> {
|
||
let globals = self.globals();
|
||
let searchers: Table = globals.get::<_, Table>("package")?.get("searchers")?;
|
||
let registry_key = self.create_registry_value(globals)?;
|
||
let searcher = Searcher::new(modules, registry_key);
|
||
searchers
|
||
.set(searchers.len()? + 1, searcher)
|
||
.map_err(|e| e.into())
|
||
}
|
||
}
|