Fixing lint warnings

src/api.rs

@@ -894,10 +894,7 @@ impl<'e> Engine<'e> {
             mut values: Vec<Dynamic>,
         ) -> Result<Dynamic, EvalAltResult> {
             let values: Vec<_> = values.iter_mut().map(Dynamic::as_mut).collect();
-
+            engine.call_fn_raw(name, values, None, Position::none())
-            let result = engine.call_fn_raw(name, values, None, Position::none());
-
-            result
         }
 
         call_fn_internal(self, name, args.into_vec()).and_then(|b| {

src/builtin.rs

@@ -837,10 +837,10 @@ impl Engine<'_> {
         }
 
         reg_fn2x!(self, "+", append, String, String, INT, bool, char);
-        self.register_fn("+", |x: String, _: ()| format!("{}", x));
+        self.register_fn("+", |x: String, _: ()| x);
 
         reg_fn2y!(self, "+", prepend, String, String, INT, bool, char);
-        self.register_fn("+", |_: (), y: String| format!("{}", y));
+        self.register_fn("+", |_: (), y: String| y);
 
         #[cfg(not(feature = "only_i32"))]
         #[cfg(not(feature = "only_i64"))]

src/call.rs

@@ -69,5 +69,5 @@ macro_rules! impl_args {
     };
 }
 
-#[cfg_attr(rustfmt, rustfmt_skip)]
+#[rustfmt::skip]
 impl_args!(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T);

src/engine.rs

@@ -31,13 +31,13 @@ pub type FnAny = dyn Fn(FnCallArgs, Position) -> Result<Dynamic, EvalAltResult>;
 
 type IteratorFn = dyn Fn(&Dynamic) -> Box<dyn Iterator<Item = Dynamic>>;
 
-pub(crate) const KEYWORD_PRINT: &'static str = "print";
+pub(crate) const KEYWORD_PRINT: &str = "print";
-pub(crate) const KEYWORD_DEBUG: &'static str = "debug";
+pub(crate) const KEYWORD_DEBUG: &str = "debug";
-pub(crate) const KEYWORD_DUMP_AST: &'static str = "dump_ast";
+pub(crate) const KEYWORD_DUMP_AST: &str = "dump_ast";
-pub(crate) const KEYWORD_TYPE_OF: &'static str = "type_of";
+pub(crate) const KEYWORD_TYPE_OF: &str = "type_of";
-pub(crate) const KEYWORD_EVAL: &'static str = "eval";
+pub(crate) const KEYWORD_EVAL: &str = "eval";
-pub(crate) const FUNC_GETTER: &'static str = "get$";
+pub(crate) const FUNC_GETTER: &str = "get$";
-pub(crate) const FUNC_SETTER: &'static str = "set$";
+pub(crate) const FUNC_SETTER: &str = "set$";
 
 #[derive(Debug, Eq, PartialEq, Hash, Clone, Copy)]
 #[cfg(not(feature = "no_index"))]
@@ -200,7 +200,7 @@ impl Engine<'_> {
         };
 
         // Argument must be a string
-        fn cast_to_string<'a>(r: &'a Variant, pos: Position) -> Result<&'a str, EvalAltResult> {
+        fn cast_to_string(r: &Variant, pos: Position) -> Result<&str, EvalAltResult> {
             r.downcast_ref::<String>()
                 .map(String::as_str)
                 .ok_or_else(|| EvalAltResult::ErrorMismatchOutputType(r.type_name().into(), pos))
@@ -615,7 +615,8 @@ impl Engine<'_> {
             // array_id[idx] = val
             IndexSourceType::Array => {
                 let arr = scope.get_mut_by_type::<Array>(src.name, src.idx);
-                Ok((arr[idx as usize] = new_val.0).into_dynamic())
+                arr[idx as usize] = new_val.0;
+                Ok(().into_dynamic())
             }
 
             // string_id[idx] = val
@@ -627,7 +628,8 @@ impl Engine<'_> {
                     .0
                     .downcast::<char>()
                     .map_err(|_| EvalAltResult::ErrorCharMismatch(pos))?;
-                Ok(Self::str_replace_char(s, idx as usize, ch).into_dynamic())
+                Self::str_replace_char(s, idx as usize, ch);
+                Ok(().into_dynamic())
             }
 
             IndexSourceType::Expression => panic!("expression cannot be indexed for update"),
@@ -795,21 +797,19 @@ impl Engine<'_> {
                     Self::search_scope(scope, id, Ok, *pos)?;
 
                 match var_type {
-                    VariableType::Constant => {
+                    VariableType::Constant => Err(EvalAltResult::ErrorAssignmentToConstant(
-                        return Err(EvalAltResult::ErrorAssignmentToConstant(
+                        id.to_string(),
-                            id.to_string(),
+                        op_pos,
-                            op_pos,
+                    )),
-                        ))
+                    _ => {
+                        let val = self.set_dot_val_helper(scope, target.as_mut(), dot_rhs, new_val);
+
+                        // In case the expression mutated `target`, we need to update it back into the scope because it is cloned.
+                        *scope.get_mut(id, idx) = target;
+
+                        val
                     }
-                    _ => (),
                 }
-
-                let val = self.set_dot_val_helper(scope, target.as_mut(), dot_rhs, new_val);
-
-                // In case the expression mutated `target`, we need to update it back into the scope because it is cloned.
-                *scope.get_mut(id, idx) = target;
-
-                val
             }
 
             // lhs[idx_expr].???
@@ -914,10 +914,10 @@ impl Engine<'_> {
                         if let Some(src) = src {
                             match src.var_type {
                                 VariableType::Constant => {
-                                    return Err(EvalAltResult::ErrorAssignmentToConstant(
+                                    Err(EvalAltResult::ErrorAssignmentToConstant(
                                         src.name.to_string(),
                                         idx_lhs.position(),
-                                    ));
+                                    ))
                                 }
                                 VariableType::Normal => Ok(Self::update_indexed_var_in_scope(
                                     src_type,
@@ -985,7 +985,7 @@ impl Engine<'_> {
                 match fn_name.as_str() {
                     // Dump AST
                     KEYWORD_DUMP_AST => {
-                        let pos = if args_expr_list.len() == 0 {
+                        let pos = if args_expr_list.is_empty() {
                             *pos
                         } else {
                             args_expr_list[0].position()
@@ -993,7 +993,7 @@ impl Engine<'_> {
 
                         // Change the argument to a debug dump of the expressions
                         let result = args_expr_list
-                            .into_iter()
+                            .iter()
                             .map(|expr| format!("{:#?}", expr))
                             .collect::<Vec<_>>()
                             .join("\n");
@@ -1049,12 +1049,12 @@ impl Engine<'_> {
                         #[cfg(feature = "no_optimize")]
                         let ast = self.compile(script).map_err(EvalAltResult::ErrorParsing)?;
 
-                        return Ok(self.eval_ast_with_scope_raw(scope, true, &ast).map_err(
+                        Ok(self
-                            |mut err| {
+                            .eval_ast_with_scope_raw(scope, true, &ast)
+                            .map_err(|mut err| {
                                 err.set_position(pos);
                                 err
-                            },
+                            })?)
-                        )?);
                     }
 
                     // Normal function call
@@ -1217,7 +1217,7 @@ impl Engine<'_> {
                     scope.pop();
                     Ok(().into_dynamic())
                 } else {
-                    return Err(EvalAltResult::ErrorFor(expr.position()));
+                    Err(EvalAltResult::ErrorFor(expr.position()))
                 }
             }
 
@@ -1245,7 +1245,7 @@ impl Engine<'_> {
                 Err(EvalAltResult::ErrorRuntime(
                     val.downcast::<String>()
                         .map(|s| *s)
-                        .unwrap_or("".to_string()),
+                        .unwrap_or_else(|_| "".to_string()),
                     *pos,
                 ))
             }

src/fn_register.rs

@@ -100,6 +100,11 @@ pub trait RegisterResultFn<FN, ARGS, RET> {
 pub struct Ref<A>(A);
 pub struct Mut<A>(A);
 
+#[inline]
+fn identity<T>(data: T) -> T {
+    data
+}
+
 macro_rules! count_args {
     () => { 0_usize };
     ( $head:ident $($tail:ident)* ) => { 1_usize + count_args!($($tail)*) };
@@ -212,9 +217,9 @@ macro_rules! def_register {
         //def_register!(imp_pop $($par => $mark => $param),*);
     };
     ($p0:ident $(, $p:ident)*) => {
-        def_register!(imp $p0 => $p0 => $p0 => Clone::clone $(, $p => $p => $p => Clone::clone)*);
+        def_register!(imp $p0 => $p0      => $p0      => Clone::clone   $(, $p => $p => $p => Clone::clone)*);
-        def_register!(imp $p0 => Ref<$p0> => &$p0 => |x| { x } $(, $p => $p => $p => Clone::clone)*);
+        def_register!(imp $p0 => Ref<$p0> => &$p0     => identity       $(, $p => $p => $p => Clone::clone)*);
-        def_register!(imp $p0 => Mut<$p0> => &mut $p0 => |x| { x } $(, $p => $p => $p => Clone::clone)*);
+        def_register!(imp $p0 => Mut<$p0> => &mut $p0 => identity       $(, $p => $p => $p => Clone::clone)*);
 
         def_register!($($p),*);
     };
@@ -224,5 +229,5 @@ macro_rules! def_register {
 //    };
 }
 
-#[cfg_attr(rustfmt, rustfmt_skip)]
+#[rustfmt::skip]
 def_register!(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T);

src/lib.rs

@@ -8,7 +8,7 @@
 //! ```,ignore
 //! fn factorial(x) {
 //!     if x == 1 { return 1; }
-//!	    x * factorial(x - 1)
+//!     x * factorial(x - 1)
 //! }
 //!
 //! compute_something(factorial(10))
@@ -22,7 +22,7 @@
 //! fn main() -> Result<(), EvalAltResult>
 //! {
 //!     fn compute_something(x: i64) -> bool {
-//!	        (x % 40) == 0
+//!         (x % 40) == 0
 //!     }
 //!
 //!     let mut engine = Engine::new();

src/optimize.rs

@@ -566,7 +566,7 @@ pub(crate) fn optimize<'a>(statements: Vec<Stmt>, engine: &Engine<'a>, scope: &S
 
     // Add back the last statement unless it is a lone No-op
     if let Some(stmt) = last_stmt {
-        if result.len() > 0 || !matches!(stmt, Stmt::Noop(_)) {
+        if !result.is_empty() || !matches!(stmt, Stmt::Noop(_)) {
             result.push(stmt);
         }
     }

src/scope.rs

@@ -77,6 +77,11 @@ impl<'a> Scope<'a> {
         self.0.len()
     }
 
+    /// Is the Scope empty?
+    pub fn is_empty(&self) -> bool {
+        self.0.len() == 0
+    }
+
     /// Add (push) a new variable to the Scope.
     pub fn push<K: Into<Cow<'a, str>>, T: Any + Clone>(&mut self, name: K, value: T) {
         let value = value.into_dynamic();
@@ -152,8 +157,7 @@ impl<'a> Scope<'a> {
             .iter()
             .enumerate()
             .rev() // Always search a Scope in reverse order
-            .find(|(_, ScopeEntry { name, .. })| name == key)
+            .any(|(_, ScopeEntry { name, .. })| name == key)
-            .is_some()
     }
 
     /// Find a variable in the Scope, starting from the last.
@@ -224,6 +228,12 @@ impl<'a> Scope<'a> {
     }
 }
 
+impl Default for Scope<'_> {
+    fn default() -> Self {
+        Scope::new()
+    }
+}
+
 impl<'a, K> iter::Extend<(K, VariableType, Dynamic)> for Scope<'a>
 where
     K: Into<Cow<'a, str>>,

tests/float.rs

@@ -1,5 +1,7 @@
 #![cfg(not(feature = "no_float"))]
-use rhai::{Engine, EvalAltResult, RegisterFn};
+use rhai::{Engine, EvalAltResult, RegisterFn, FLOAT};
+
+const EPSILON: FLOAT = 0.000_000_000_1;
 
 #[test]
 fn test_float() -> Result<(), EvalAltResult> {
@@ -13,7 +15,7 @@ fn test_float() -> Result<(), EvalAltResult> {
         engine.eval::<bool>("let x = 0.0; let y = 1.0; x > y")?,
         false
     );
-    assert_eq!(engine.eval::<f64>("let x = 9.9999; x")?, 9.9999);
+    assert!((engine.eval::<FLOAT>("let x = 9.9999; x")? - 9.9999 as FLOAT).abs() < EPSILON);
 
     Ok(())
 }
@@ -51,13 +53,12 @@ fn struct_with_float() -> Result<(), EvalAltResult> {
     engine.register_fn("update", TestStruct::update);
     engine.register_fn("new_ts", TestStruct::new);
 
-    assert_eq!(
+    assert!(
-        engine.eval::<f64>("let ts = new_ts(); ts.update(); ts.x")?,
+        (engine.eval::<FLOAT>("let ts = new_ts(); ts.update(); ts.x")? - 6.789).abs() < EPSILON
-        6.789
     );
-    assert_eq!(
+    assert!(
-        engine.eval::<f64>("let ts = new_ts(); ts.x = 10.1001; ts.x")?,
+        (engine.eval::<FLOAT>("let ts = new_ts(); ts.x = 10.1001; ts.x")? - 10.1001).abs()
-        10.1001
+            < EPSILON
     );
 
     Ok(())

tests/math.rs

@@ -13,7 +13,7 @@ fn test_math() -> Result<(), EvalAltResult> {
     #[cfg(not(feature = "only_i32"))]
     assert_eq!(
         engine.eval::<INT>("(-9223372036854775807).abs()")?,
-        9223372036854775807
+        9_223_372_036_854_775_807
     );
 
     #[cfg(feature = "only_i32")]

tests/power_of.rs

@@ -4,7 +4,7 @@ use rhai::{Engine, EvalAltResult, INT};
 use rhai::FLOAT;
 
 #[cfg(not(feature = "no_float"))]
-const EPSILON: FLOAT = 0.0000000001;
+const EPSILON: FLOAT = 0.000_000_000_1;
 
 #[test]
 fn test_power_of() -> Result<(), EvalAltResult> {
@@ -16,11 +16,11 @@ fn test_power_of() -> Result<(), EvalAltResult> {
     #[cfg(not(feature = "no_float"))]
     {
         assert!(
-            (engine.eval::<FLOAT>("2.2 ~ 3.3")? - 13.489468760533386 as FLOAT).abs() <= EPSILON
+            (engine.eval::<FLOAT>("2.2 ~ 3.3")? - 13.489_468_760_533_386 as FLOAT).abs() <= EPSILON
         );
-        assert_eq!(engine.eval::<FLOAT>("2.0~-2.0")?, 0.25 as FLOAT);
+        assert!((engine.eval::<FLOAT>("2.0~-2.0")? - 0.25 as FLOAT).abs() < EPSILON);
-        assert_eq!(engine.eval::<FLOAT>("(-2.0~-2.0)")?, 0.25 as FLOAT);
+        assert!((engine.eval::<FLOAT>("(-2.0~-2.0)")? - 0.25 as FLOAT).abs() < EPSILON);
-        assert_eq!(engine.eval::<FLOAT>("(-2.0~-2)")?, 0.25 as FLOAT);
+        assert!((engine.eval::<FLOAT>("(-2.0~-2)")? - 0.25 as FLOAT).abs() < EPSILON);
         assert_eq!(engine.eval::<INT>("4~3")?, 64);
     }
 
@@ -37,20 +37,18 @@ fn test_power_of_equals() -> Result<(), EvalAltResult> {
     #[cfg(not(feature = "no_float"))]
     {
         assert!(
-            (engine.eval::<FLOAT>("let x = 2.2; x ~= 3.3; x")? - 13.489468760533386 as FLOAT).abs()
+            (engine.eval::<FLOAT>("let x = 2.2; x ~= 3.3; x")? - 13.489_468_760_533_386 as FLOAT)
+                .abs()
                 <= EPSILON
         );
-        assert_eq!(
+        assert!(
-            engine.eval::<FLOAT>("let x = 2.0; x ~= -2.0; x")?,
+            (engine.eval::<FLOAT>("let x = 2.0; x ~= -2.0; x")? - 0.25 as FLOAT).abs() < EPSILON
-            0.25 as FLOAT
         );
-        assert_eq!(
+        assert!(
-            engine.eval::<FLOAT>("let x = -2.0; x ~= -2.0; x")?,
+            (engine.eval::<FLOAT>("let x = -2.0; x ~= -2.0; x")? - 0.25 as FLOAT).abs() < EPSILON
-            0.25 as FLOAT
         );
-        assert_eq!(
+        assert!(
-            engine.eval::<FLOAT>("let x = -2.0; x ~= -2; x")?,
+            (engine.eval::<FLOAT>("let x = -2.0; x ~= -2; x")? - 0.25 as FLOAT).abs() < EPSILON
-            0.25 as FLOAT
         );
         assert_eq!(engine.eval::<INT>("let x =4; x ~= 3; x")?, 64);
     }

tests/unit.rs

@@ -3,7 +3,7 @@ use rhai::{Engine, EvalAltResult};
 #[test]
 fn test_unit() -> Result<(), EvalAltResult> {
     let mut engine = Engine::new();
-    assert_eq!(engine.eval::<()>("let x = (); x")?, ());
+    engine.eval::<()>("let x = (); x")?;
     Ok(())
 }
 
@@ -17,6 +17,6 @@ fn test_unit_eq() -> Result<(), EvalAltResult> {
 #[test]
 fn test_unit_with_spaces() -> Result<(), EvalAltResult> {
     let mut engine = Engine::new();
-    assert_eq!(engine.eval::<()>("let x = ( ); x")?, ());
+    engine.eval::<()>("let x = ( ); x")?;
     Ok(())
 }

tests/var_scope.rs

@@ -9,7 +9,7 @@ fn test_var_scope() -> Result<(), EvalAltResult> {
     assert_eq!(engine.eval_with_scope::<INT>(&mut scope, "x")?, 9);
     engine.eval_with_scope::<()>(&mut scope, "x = x + 1; x = x + 2;")?;
     assert_eq!(engine.eval_with_scope::<INT>(&mut scope, "x")?, 12);
-    assert_eq!(engine.eval_with_scope::<()>(&mut scope, "{let x = 3}")?, ());
+    engine.eval_with_scope::<()>(&mut scope, "{let x = 3}")?;
     assert_eq!(engine.eval_with_scope::<INT>(&mut scope, "x")?, 12);
 
     Ok(())