kjuulh/rhai
1
0
Fork 0
Code Issues 1 Pull Requests 1 Packages Projects Releases Wiki Activity

Merge pull request #630 from schungx/master

Browse Source 
Allow if and switch expressions.
This commit is contained in:
Stephen Chung 2022-08-27 13:35:33 +08:00 committed by GitHub
commit 855503bcaf
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
10 changed files with 182 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
CHANGELOG.md
View File

@ -9,6 +9,7 @@ Bug fixes
* API for registering property getters/setters and indexers to an `Engine` now works with functions that take a first parameter of `NativeCallContext`.
* Missing API function `Module::set_getter_setter_fn` is added.
* To avoid subtle errors, simple optimization is used for `rhai-run`; previous it was full optimization.
Deprecated API
--------------
@ -22,10 +23,17 @@ New features
* For very special needs, the ability to register fallible type iterators is added.
### Expressions
* `if`-expressions are allowed in `Engine::eval_expression` and `Engine::compile_expression` provided that both statement blocks each contain at most a single expression.
* `switch`-expressions are allowed in `Engine::eval_expression` and `Engine::compile_expression` provided that match actions are expressions only.
Enhancements
------------
* `is_empty` method is added to arrays, BLOB's, object maps, strings and ranges.
* `StaticModuleResolver` now stores the path in the module's `id` field.
* `Engine::module_resolver` is added to grant access to the `Engine`'s module resolver.
Version 1.9.0

2
src/api/compile.rs
View File

@ -113,7 +113,7 @@ impl Engine {
});
}
let mut ast = self.compile_scripts_with_scope(scope, &[script])?;
let mut ast = self.compile_with_scope(scope, script)?;
let mut resolver = StaticModuleResolver::new();
let mut imports = BTreeSet::new();

9
src/api/mod.rs
View File

@ -70,6 +70,15 @@ pub mod default_limits {
}
impl Engine {
/// The module resolution service used by the [`Engine`].
///
/// Not available under `no_module`.
#[cfg(not(feature = "no_module"))]
#[inline(always)]
pub fn module_resolver(&self) -> &dyn crate::ModuleResolver {
&*self.module_resolver
}
/// Set the module resolution service used by the [`Engine`].
///
/// Not available under `no_module`.

2
src/bin/rhai-run.rs
View File

@ -51,7 +51,7 @@ fn main() {
let mut engine = Engine::new();
#[cfg(not(feature = "no_optimize"))]
engine.set_optimization_level(rhai::OptimizationLevel::Full);
engine.set_optimization_level(rhai::OptimizationLevel::Simple);
let mut f = match File::open(&filename) {
Err(err) => {

10
src/func/native.rs
View File

@ -227,7 +227,7 @@ impl<'a> NativeCallContext<'a> {
#[cfg(not(feature = "no_module"))]
#[inline]
pub fn iter_imports(&self) -> impl Iterator<Item = (&str, &Module)> {
self.global.iter().flat_map(|&m| m.iter_imports())
self.global.iter().flat_map(|&g| g.iter_imports())
}
/// Get an iterator over the current set of modules imported via `import` statements in reverse order.
#[cfg(not(feature = "no_module"))]
@ -236,7 +236,7 @@ impl<'a> NativeCallContext<'a> {
pub(crate) fn iter_imports_raw(
&self,
) -> impl Iterator<Item = (&crate::ImmutableString, &Shared<Module>)> {
self.global.iter().flat_map(|&m| m.iter_imports_raw())
self.global.iter().flat_map(|&g| g.iter_imports_raw())
}
/// _(internals)_ The current [`GlobalRuntimeState`], if any.
/// Exported under the `internals` feature only.
@ -249,12 +249,12 @@ impl<'a> NativeCallContext<'a> {
self.global
}
/// Get an iterator over the namespaces containing definitions of all script-defined functions
/// in reverse order.
/// in reverse order (i.e. parent namespaces are iterated after child namespaces).
#[inline]
pub fn iter_namespaces(&self) -> impl Iterator<Item = &Module> {
self.lib.iter().rev().copied()
self.lib.iter().copied()
}
/// _(internals)_ The current set of namespaces containing definitions of all script-defined functions.
/// _(internals)_ The current stack of namespaces containing definitions of all script-defined functions.
/// Exported under the `internals` feature only.
#[cfg(feature = "internals")]
#[inline(always)]

6
src/module/mod.rs
View File

@ -1960,9 +1960,6 @@ impl Module {
/// The entire [`AST`][crate::AST] is encapsulated into each function, allowing functions to
/// cross-call each other.
///
/// Functions in the global namespace, plus all functions defined in the [`Module`], are
/// _merged_ into a _unified_ namespace. Therefore, all functions will be found.
///
/// # Example
///
/// ```
@ -1993,9 +1990,6 @@ impl Module {
/// The entire [`AST`][crate::AST] is encapsulated into each function, allowing functions to
/// cross-call each other.
///
/// Functions in the global namespace, plus all functions defined in the [`Module`], are
/// _merged_ into a _unified_ namespace. Therefore, all functions will be found.
///
/// # WARNING - Low Level API
///
/// This function is very low level.

8
src/module/resolvers/stat.rs
View File

@ -54,8 +54,14 @@ impl StaticModuleResolver {
/// Add a [module][Module] keyed by its path.
#[inline]
pub fn insert(&mut self, path: impl Into<Identifier>, mut module: Module) {
let path = path.into();
if module.id().is_none() {
module.set_id(path.clone());
}
module.build_index();
self.0.insert(path.into(), module.into());
self.0.insert(path, module.into());
}
/// Remove a [module][Module] given its path.
#[inline(always)]

40
src/parser.rs
View File

@ -291,6 +291,8 @@ struct ParseSettings {
in_closure: bool,
/// Is the construct being parsed located inside a breakable loop?
is_breakable: bool,
/// Allow statements in blocks?
allow_statements: bool,
/// Language options in effect (overrides Engine options).
options: LangOptions,
/// Current expression nesting level.
@ -1193,12 +1195,21 @@ impl Engine {
}
};
let stmt = self.parse_stmt(input, state, lib, settings.level_up())?;
let need_comma = !stmt.is_self_terminated();
let (action_expr, need_comma) = if settings.allow_statements {
let stmt = self.parse_stmt(input, state, lib, settings.level_up())?;
let need_comma = !stmt.is_self_terminated();
let stmt_block: StmtBlock = stmt.into();
(Expr::Stmt(stmt_block.into()), need_comma)
} else {
(
self.parse_expr(input, state, lib, settings.level_up())?,
true,
)
};
let has_condition = !matches!(condition, Expr::BoolConstant(true, ..));
let stmt_block: StmtBlock = stmt.into();
expressions.push((condition, Expr::Stmt(stmt_block.into())).into());
expressions.push((condition, action_expr).into());
let index = expressions.len() - 1;
if case_expr_list.is_empty() {
@ -3076,6 +3087,22 @@ impl Engine {
let mut statements = StaticVec::new_const();
if !settings.allow_statements {
let stmt = self.parse_expr_stmt(input, state, lib, settings.level_up())?;
statements.push(stmt);
// Must end with }
return match input.next().expect(NEVER_ENDS) {
(Token::RightBrace, pos) => Ok((statements, settings.pos, pos).into()),
(Token::LexError(err), pos) => Err(err.into_err(pos)),
(.., pos) => Err(PERR::MissingToken(
Token::LeftBrace.into(),
"to start a statement block".into(),
)
.into_err(pos)),
};
}
let prev_entry_stack_len = state.block_stack_len;
state.block_stack_len = state.stack.len();
@ -3290,6 +3317,7 @@ impl Engine {
#[cfg(not(feature = "no_closure"))]
in_closure: false,
is_breakable: false,
allow_statements: true,
level: 0,
options,
pos,
@ -3761,7 +3789,7 @@ impl Engine {
let mut functions = BTreeMap::new();
let mut options = self.options;
options.remove(LangOptions::IF_EXPR | LangOptions::SWITCH_EXPR | LangOptions::STMT_EXPR);
options.remove(LangOptions::STMT_EXPR);
#[cfg(not(feature = "no_function"))]
options.remove(LangOptions::ANON_FN);
@ -3773,6 +3801,7 @@ impl Engine {
#[cfg(not(feature = "no_closure"))]
in_closure: false,
is_breakable: false,
allow_statements: false,
level: 0,
options,
pos: Position::NONE,
@ -3828,6 +3857,7 @@ impl Engine {
#[cfg(not(feature = "no_closure"))]
in_closure: false,
is_breakable: false,
allow_statements: true,
options: self.options,
level: 0,
pos: Position::NONE,

41
tests/expressions.rs
View File

@ -12,8 +12,47 @@ fn test_expressions() -> Result<(), Box<EvalAltResult>> {
engine.eval_expression_with_scope::<INT>(&mut scope, "2 + (x + 10) * 2")?,
42
);
assert_eq!(
engine.eval_expression_with_scope::<INT>(&mut scope, "if x > 0 { 42 } else { 123 }")?,
42
);
assert!(engine
.eval_expression_with_scope::<INT>(&mut scope, "if x > 0 { 42 } else { 123 }")
.eval_expression_with_scope::<INT>(&mut scope, "if x > 0 { let y = 42; y } else { 123 }")
.is_err());
assert!(engine
.eval_expression_with_scope::<INT>(&mut scope, "if x > 0 { 42 } else { let y = 123; y }")
.is_err());
assert!(engine
.eval_expression_with_scope::<INT>(&mut scope, "if x > 0 { 42 } else {}")
.is_err());
assert_eq!(
engine.eval_expression_with_scope::<INT>(
&mut scope,
"
switch x {
0 => 1,
1..10 => 123,
10 => 42,
}
"
)?,
42
);
assert!(engine
.eval_expression_with_scope::<INT>(
&mut scope,
"
switch x {
0 => 1,
1..10 => {
let y = 123;
y
}
10 => 42,
}
"
)
.is_err());
assert!(engine.eval_expression::<()>("40 + 2;").is_err());

82
tests/modules.rs
View File

@ -1,8 +1,8 @@
#![cfg(not(feature = "no_module"))]
use rhai::{
module_resolvers::{DummyModuleResolver, StaticModuleResolver},
Dynamic, Engine, EvalAltResult, FnNamespace, ImmutableString, Module, ParseError,
ParseErrorType, Scope, INT,
Dynamic, Engine, EvalAltResult, FnNamespace, FnPtr, ImmutableString, Module, NativeCallContext,
ParseError, ParseErrorType, Scope, Shared, INT,
};
#[test]
@ -459,10 +459,10 @@ fn test_module_str() -> Result<(), Box<EvalAltResult>> {
#[cfg(not(feature = "no_function"))]
#[test]
fn test_module_ast_namespace() -> Result<(), Box<EvalAltResult>> {
let script = r#"
let script = "
fn foo(x) { x + 1 }
fn bar(x) { foo(x) }
"#;
";
let mut engine = Engine::new();
@ -499,11 +499,11 @@ fn test_module_ast_namespace() -> Result<(), Box<EvalAltResult>> {
fn test_module_ast_namespace2() -> Result<(), Box<EvalAltResult>> {
use rhai::{Engine, Module, Scope};
const MODULE_TEXT: &str = r#"
const MODULE_TEXT: &str = "
fn run_function(function) {
call(function)
}
"#;
";
const SCRIPT: &str = r#"
import "test_module" as test;
@ -527,6 +527,76 @@ fn test_module_ast_namespace2() -> Result<(), Box<EvalAltResult>> {
Ok(())
}
#[cfg(not(feature = "no_function"))]
#[cfg(feature = "internals")]
#[test]
fn test_module_context() -> Result<(), Box<EvalAltResult>> {
let script = "fn bar() { calc(|x| x + 1) }";
let mut engine = Engine::new();
let ast = engine.compile(script)?;
let module = Module::eval_ast_as_new(Scope::new(), &ast, &engine)?;
let mut resolver = StaticModuleResolver::new();
resolver.insert("testing", module);
engine.set_module_resolver(resolver);
engine.register_fn(
"calc",
|context: NativeCallContext, fp: FnPtr| -> Result<INT, Box<EvalAltResult>> {
// Store fields for later use
let engine = context.engine();
let fn_name = context.fn_name().to_string();
let source = context.source().map(|s| s.to_string());
let global = context.global_runtime_state().unwrap().clone();
let pos = context.position();
let call_level = context.call_level();
// Store the paths of the stack of call modules up to this point
let modules_list: Vec<String> = context
.iter_namespaces()
.map(|m| m.id().unwrap_or("testing"))
.filter(|id| !id.is_empty())
.map(|id| id.to_string())
.collect();
// Recreate the 'NativeCallContext' - requires the 'internals' feature
let mut libraries = Vec::<Shared<Module>>::new();
for path in modules_list {
// Recreate the stack of call modules by resolving each path with
// the module resolver.
let module = engine.module_resolver().resolve(engine, None, &path, pos)?;
libraries.push(module);
}
let lib: Vec<&Module> = libraries.iter().map(|m| m.as_ref()).collect();
let new_context = NativeCallContext::new_with_all_fields(
engine,
&fn_name,
source.as_ref().map(|s| s.as_str()),
&global,
&lib,
pos,
call_level,
);
fp.call_within_context(&new_context, (41 as INT,))
},
);
assert_eq!(
engine.eval::<INT>(r#"import "testing" as t; t::bar()"#)?,
42
);
Ok(())
}
#[test]
fn test_module_file() -> Result<(), Box<EvalAltResult>> {
let engine = Engine::new();