Merge branch 'main' into main

CHANGELOG.md

@@ -16,6 +16,18 @@
 
 ### Contributors
 
+## [10.0.0](https://github.com/ISibboI/evalexpr/compare/9.1.0...10.0.0) - 2023-05-21
+
+### Added
+
+ * Builtin functions can now be disabled (#129)
+
+### Contributors
+
+My warmhearted thanks goes to:
+
+ * [hexofyore](https://github.com/hexofyore)
+
 ## [9.1.0](https://github.com/ISibboI/evalexpr/compare/9.0.0...9.1.0) - 2023-05-16
 
 ### Added
@@ -28,23 +40,6 @@ My warmhearted thanks goes to:
 
  * [nickisyourfan](https://github.com/nickisyourfan)
 
-## [8.2.0](https://github.com/ISibboI/evalexpr/compare/8.1.0...8.2.0) - 2023-04-13
-
-### Added
-
-* `EvalExprError` now derives `Clone` (#116)
-
-### Changed
-
-* Occurrences of `f64` and `i64` have been replaced with the type aliases `FloatType` and `IntType` where applicable (#113)
-
-### Contributors
-
-My warmhearted thanks goes to:
-
-* [Natan Freeman](https://github.com/NatanFreeman)
-* [Claus Matzinger](https://github.com/celaus)
-
 ## [9.0.0](https://github.com/ISibboI/evalexpr/compare/8.2.0...9.0.0) - 2023-04-13
 
 ### Fixed

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "evalexpr"
-version = "9.1.0"
+version = "10.0.0"
 description = "A powerful arithmetic and boolean expression evaluator"
 keywords = ["expression", "evaluate", "evaluator", "arithmetic", "boolean"]
 categories = ["parsing", "game-engines"]

README.md

@@ -334,7 +334,20 @@ For more information about user-defined functions, refer to the respective [sect
 
 ### Builtin Functions
 
-This crate offers a set of builtin functions.
+This crate offers a set of builtin functions (see below for a full list).
+They can be disabled if needed as follows:
+
+```rust
+use evalexpr::*;
+let mut context = HashMapContext::new();
+assert_eq!(eval_with_context("max(1,3)",&context),Ok(Value::from(3)));
+context.set_builtin_functions_disabled(true).unwrap(); // Do proper error handling here
+assert_eq!(eval_with_context("max(1,3)",&context),Err(EvalexprError::FunctionIdentifierNotFound(String::from("max"))));
+```
+
+Not all contexts support enabling or disabling builtin functions.
+Specifically the `EmptyContext` has builtin functions disabled by default, and they cannot be enabled.
+Symmetrically, the `EmptyContextWithBuiltinFunctions` has builtin functions enabled by default, and they cannot be disabled.
 
 | Identifier           | Argument Amount | Argument Types                | Description |
 |----------------------|-----------------|-------------------------------|-------------|

src/context/mod.rs

@@ -22,6 +22,13 @@ pub trait Context {
     /// Calls the function that is linked to the given identifier with the given argument.
     /// If no function with the given identifier is found, this method returns `EvalexprError::FunctionIdentifierNotFound`.
     fn call_function(&self, identifier: &str, argument: &Value) -> EvalexprResult<Value>;
+
+    /// Checks if builtin functions are disabled.
+    fn are_builtin_functions_disabled(&self) -> bool;
+
+    /// Disables builtin functions if `disabled` is `true`, and enables them otherwise.
+    /// If the context does not support enabling or disabling builtin functions, an error is returned.
+    fn set_builtin_functions_disabled(&mut self, disabled: bool) -> EvalexprResult<()>;
 }
 
 /// A context that allows to assign to variables.
@@ -66,6 +73,7 @@ pub trait GetFunctionContext: Context {
 }*/
 
 /// A context that returns `None` for each identifier.
+/// Builtin functions are disabled and cannot be enabled.
 #[derive(Debug, Default)]
 pub struct EmptyContext;
 
@@ -79,6 +87,20 @@ impl Context for EmptyContext {
             identifier.to_string(),
         ))
     }
+
+    /// Builtin functions are always disabled for `EmptyContext`.
+    fn are_builtin_functions_disabled(&self) -> bool {
+        true
+    }
+
+    /// Builtin functions can't be enabled for `EmptyContext`.
+    fn set_builtin_functions_disabled(&mut self, disabled: bool) -> EvalexprResult<()> {
+        if disabled {
+            Ok(())
+        } else {
+            Err(EvalexprError::BuiltinFunctionsCannotBeEnabled)
+        }
+    }
 }
 
 impl<'a> IterateVariablesContext<'a> for EmptyContext {
@@ -94,6 +116,50 @@ impl<'a> IterateVariablesContext<'a> for EmptyContext {
     }
 }
 
+/// A context that returns `None` for each identifier.
+/// Builtin functions are enabled and cannot be disabled.
+#[derive(Debug, Default)]
+pub struct EmptyContextWithBuiltinFunctions;
+
+impl Context for EmptyContextWithBuiltinFunctions {
+    fn get_value(&self, _identifier: &str) -> Option<&Value> {
+        None
+    }
+
+    fn call_function(&self, identifier: &str, _argument: &Value) -> EvalexprResult<Value> {
+        Err(EvalexprError::FunctionIdentifierNotFound(
+            identifier.to_string(),
+        ))
+    }
+
+    /// Builtin functions are always enabled for EmptyContextWithBuiltinFunctions.
+    fn are_builtin_functions_disabled(&self) -> bool {
+        false
+    }
+
+    /// Builtin functions can't be disabled for EmptyContextWithBuiltinFunctions.
+    fn set_builtin_functions_disabled(&mut self, disabled: bool) -> EvalexprResult<()> {
+        if disabled {
+            Err(EvalexprError::BuiltinFunctionsCannotBeDisabled)
+        } else {
+            Ok(())
+        }
+    }
+}
+
+impl<'a> IterateVariablesContext<'a> for EmptyContextWithBuiltinFunctions {
+    type VariableIterator = iter::Empty<(String, Value)>;
+    type VariableNameIterator = iter::Empty<String>;
+
+    fn iter_variables(&self) -> Self::VariableIterator {
+        iter::empty()
+    }
+
+    fn iter_variable_names(&self) -> Self::VariableNameIterator {
+        iter::empty()
+    }
+}
+
 /// A context that stores its mappings in hash maps.
 ///
 /// *Value and function mappings are stored independently, meaning that there can be a function and a value with the same identifier.*
@@ -105,6 +171,9 @@ pub struct HashMapContext {
     variables: HashMap<String, Value>,
     #[cfg_attr(feature = "serde_support", serde(skip))]
     functions: HashMap<String, Function>,
+
+    /// True if builtin functions are disabled.
+    without_builtin_functions: bool,
 }
 
 impl HashMapContext {
@@ -128,6 +197,15 @@ impl Context for HashMapContext {
             ))
         }
     }
+
+    fn set_builtin_functions_disabled(&mut self, disabled: bool) -> EvalexprResult<()> {
+        self.without_builtin_functions = disabled;
+        Ok(())
+    }
+
+    fn are_builtin_functions_disabled(&self) -> bool {
+        self.without_builtin_functions
+    }
 }
 
 impl ContextWithMutableVariables for HashMapContext {

src/error/display.rs

@@ -113,6 +113,12 @@ impl fmt::Display for EvalexprError {
                 regex, message
             ),
             ContextNotMutable => write!(f, "Cannot manipulate context"),
+            BuiltinFunctionsCannotBeEnabled => {
+                write!(f, "This context does not allow enabling builtin functions")
+            },
+            BuiltinFunctionsCannotBeDisabled => {
+                write!(f, "This context does not allow disabling builtin functions")
+            },
             IllegalEscapeSequence(string) => write!(f, "Illegal escape sequence: {}", string),
             CustomMessage(message) => write!(f, "Error: {}", message),
         }

src/error/mod.rs

@@ -203,6 +203,12 @@ pub enum EvalexprError {
     /// An escape sequence within a string literal is illegal.
     IllegalEscapeSequence(String),
 
+    /// This context does not allow enabling builtin functions.
+    BuiltinFunctionsCannotBeEnabled,
+
+    /// This context does not allow disabling builtin functions.
+    BuiltinFunctionsCannotBeDisabled,
+
     /// A custom error explained by its message.
     CustomMessage(String),
 }

src/lib.rs

@@ -317,7 +317,20 @@
 //!
 //! ### Builtin Functions
 //!
-//! This crate offers a set of builtin functions.
+//! This crate offers a set of builtin functions (see below for a full list).
+//! They can be disabled if needed as follows:
+//!
+//! ```rust
+//! use evalexpr::*;
+//! let mut context = HashMapContext::new();
+//! assert_eq!(eval_with_context("max(1,3)",&context),Ok(Value::from(3)));
+//! context.set_builtin_functions_disabled(true).unwrap(); // Do proper error handling here
+//! assert_eq!(eval_with_context("max(1,3)",&context),Err(EvalexprError::FunctionIdentifierNotFound(String::from("max"))));
+//! ```
+//!
+//! Not all contexts support enabling or disabling builtin functions.
+//! Specifically the `EmptyContext` has builtin functions disabled by default, and they cannot be enabled.
+//! Symmetrically, the `EmptyContextWithBuiltinFunctions` has builtin functions enabled by default, and they cannot be disabled.
 //!
 //! | Identifier           | Argument Amount | Argument Types                | Description |
 //! |----------------------|-----------------|-------------------------------|-------------|
@@ -539,7 +552,7 @@ extern crate serde_derive;
 pub use crate::{
     context::{
         Context, ContextWithMutableFunctions, ContextWithMutableVariables, EmptyContext,
-        HashMapContext, IterateVariablesContext,
+        EmptyContextWithBuiltinFunctions, HashMapContext, IterateVariablesContext,
     },
     error::{EvalexprError, EvalexprResult},
     function::Function,

src/operator/mod.rs

@@ -459,7 +459,9 @@ impl Operator {
                 let arguments = &arguments[0];
 
                 match context.call_function(identifier, arguments) {
-                    Err(EvalexprError::FunctionIdentifierNotFound(_)) => {
+                    Err(EvalexprError::FunctionIdentifierNotFound(_))
+                        if !context.are_builtin_functions_disabled() =>
+                    {
                         if let Some(builtin_function) = builtin_function(identifier) {
                             builtin_function.call(arguments)
                         } else {

tests/integration.rs

@@ -1520,12 +1520,39 @@ fn test_type_errors_in_binary_operators() {
 
 #[test]
 fn test_empty_context() {
-    let context = EmptyContext;
+    let mut context = EmptyContext;
     assert_eq!(context.get_value("abc"), None);
     assert_eq!(
         context.call_function("abc", &Value::Empty),
         Err(EvalexprError::FunctionIdentifierNotFound("abc".to_owned()))
     );
+    assert_eq!(
+        eval_with_context("max(1,3)", &context),
+        Err(EvalexprError::FunctionIdentifierNotFound(String::from(
+            "max"
+        )))
+    );
+    assert_eq!(context.set_builtin_functions_disabled(true), Ok(()));
+    assert_eq!(
+        context.set_builtin_functions_disabled(false),
+        Err(EvalexprError::BuiltinFunctionsCannotBeEnabled)
+    )
+}
+
+#[test]
+fn test_empty_context_with_builtin_functions() {
+    let mut context = EmptyContextWithBuiltinFunctions;
+    assert_eq!(context.get_value("abc"), None);
+    assert_eq!(
+        context.call_function("abc", &Value::Empty),
+        Err(EvalexprError::FunctionIdentifierNotFound("abc".to_owned()))
+    );
+    assert_eq!(eval_with_context("max(1,3)", &context), Ok(Value::Int(3)));
+    assert_eq!(context.set_builtin_functions_disabled(false), Ok(()));
+    assert_eq!(
+        context.set_builtin_functions_disabled(true),
+        Err(EvalexprError::BuiltinFunctionsCannotBeDisabled)
+    );
 }
 
 #[test]
@@ -2248,3 +2275,19 @@ fn test_negative_power() {
     assert_eq!(eval("(-3)^-2"), Ok(Value::Float(1.0 / 9.0)));
     assert_eq!(eval("-(3^-2)"), Ok(Value::Float(-1.0 / 9.0)));
 }
+
+#[test]
+fn test_builtin_functions_context() {
+    let mut context = HashMapContext::new();
+    // Builtin functions are enabled by default for HashMapContext.
+    assert_eq!(eval_with_context("max(1,3)", &context), Ok(Value::from(3)));
+    // Disabling builtin function in Context.
+    context.set_builtin_functions_disabled(true).unwrap();
+    // Builtin functions are disabled and using them returns an error.
+    assert_eq!(
+        eval_with_context("max(1,3)", &context),
+        Err(EvalexprError::FunctionIdentifierNotFound(String::from(
+            "max"
+        )))
+    );
+}