Implement `JsRegExp` (#2326)

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This Pull Request is related to #2098.

It changes the following:

- Implements `JsRegExp`
- Adds a brief `JsRegExp` example under `boa_examples`

boa_engine/src/builtins/regexp/mod.rs

@@ -231,7 +231,7 @@ impl RegExp {
     ///  - [ECMAScript reference][spec]
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-regexpalloc
-    fn alloc(new_target: &JsValue, context: &mut Context) -> JsResult<JsObject> {
+    pub(crate) fn alloc(new_target: &JsValue, context: &mut Context) -> JsResult<JsObject> {
         // 1. Let obj be ? OrdinaryCreateFromConstructor(newTarget, "%RegExp.prototype%", « [[RegExpMatcher]], [[OriginalSource]], [[OriginalFlags]] »).
         let proto =
             get_prototype_from_constructor(new_target, StandardConstructors::regexp, context)?;
@@ -259,7 +259,7 @@ impl RegExp {
     ///  - [ECMAScript reference][spec]
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-regexpinitialize
-    fn initialize(
+    pub(crate) fn initialize(
         obj: JsObject,
         pattern: &JsValue,
         flags: &JsValue,

boa_engine/src/object/builtins/jsregexp.rs

@@ -0,0 +1,269 @@
+//! This module implements a wrapper for the `RegExp` Builtin Javascript Object
+use crate::{
+    builtins::RegExp,
+    object::{JsArray, JsObject, JsObjectType},
+    Context, JsResult, JsValue,
+};
+
+use boa_gc::{Finalize, Trace};
+use std::ops::Deref;
+
+/// `JsRegExp` provides a wrapper for Boa's implementation of the JavaScript `RegExp` builtin object
+///
+/// # Examples
+///
+/// Create a `JsRegExp` and run RegExp.prototype.test( String )
+///
+/// ```
+/// # use boa_engine::{
+/// #  object::builtins::JsRegExp,
+/// #  Context, JsValue,
+/// # };
+///
+/// // Initialize the `Context`
+/// let context = &mut Context::default();
+///
+/// // Create a new RegExp with pattern and flags
+/// let regexp = JsRegExp::new("foo", "gi", context).unwrap();
+///
+/// let test_result = regexp.test("football", context).unwrap();
+/// assert!(test_result);
+///
+/// let to_string = regexp.to_string(context).unwrap();
+/// assert_eq!(to_string, String::from("/foo/gi"));
+///
+/// ```
+///
+#[derive(Debug, Clone, Trace, Finalize)]
+pub struct JsRegExp {
+    inner: JsObject,
+}
+
+impl JsRegExp {
+    /// Create a new `JsRegExp` object
+    /// ```
+    /// # use boa_engine::{
+    /// #  object::builtins::JsRegExp,
+    /// #  Context, JsValue,
+    /// # };
+    /// // Initialize the `Context`
+    /// let context = &mut Context::default();
+    ///
+    /// // Create a new RegExp with pattern and flags
+    /// let regexp = JsRegExp::new("foo", "gi", context).unwrap();
+    /// ```
+    #[inline]
+    pub fn new<S>(pattern: S, flags: S, context: &mut Context) -> JsResult<Self>
+    where
+        S: Into<JsValue>,
+    {
+        let constructor = &context
+            .intrinsics()
+            .constructors()
+            .regexp()
+            .constructor()
+            .into();
+        let obj = RegExp::alloc(constructor, context)?;
+
+        let regexp = RegExp::initialize(obj, &pattern.into(), &flags.into(), context)?
+            .as_object()
+            .expect("RegExp::initialize must return a RegExp object")
+            .clone();
+
+        Ok(Self { inner: regexp })
+    }
+
+    /// Create a `JsRegExp` from a regular expression `JsObject`
+    #[inline]
+    pub fn from_object(object: JsObject, context: &mut Context) -> JsResult<Self> {
+        if object.borrow().is_regexp() {
+            Ok(Self { inner: object })
+        } else {
+            context.throw_type_error("object is not a RegExp")
+        }
+    }
+
+    /// Returns a boolean value for whether the `d` flag is present in `JsRegExp` flags
+    #[inline]
+    pub fn has_indices(&self, context: &mut Context) -> JsResult<bool> {
+        RegExp::get_has_indices(&self.inner.clone().into(), &[], context)
+            .map(|v| v.as_boolean().expect("value must be a bool"))
+    }
+
+    /// Returns a boolean value for whether the `g` flag is present in `JsRegExp` flags
+    #[inline]
+    pub fn global(&self, context: &mut Context) -> JsResult<bool> {
+        RegExp::get_global(&self.inner.clone().into(), &[], context)
+            .map(|v| v.as_boolean().expect("value must be a bool"))
+    }
+
+    /// Returns a boolean value for whether the `i` flag is present in `JsRegExp` flags
+    #[inline]
+    pub fn ignore_case(&self, context: &mut Context) -> JsResult<bool> {
+        RegExp::get_ignore_case(&self.inner.clone().into(), &[], context)
+            .map(|v| v.as_boolean().expect("value must be a bool"))
+    }
+
+    /// Returns a boolean value for whether the `m` flag is present in `JsRegExp` flags
+    #[inline]
+    pub fn multiline(&self, context: &mut Context) -> JsResult<bool> {
+        RegExp::get_multiline(&self.inner.clone().into(), &[], context)
+            .map(|v| v.as_boolean().expect("value must be a bool"))
+    }
+
+    /// Returns a boolean value for whether the `s` flag is present in `JsRegExp` flags
+    #[inline]
+    pub fn dot_all(&self, context: &mut Context) -> JsResult<bool> {
+        RegExp::get_dot_all(&self.inner.clone().into(), &[], context)
+            .map(|v| v.as_boolean().expect("value must be a bool"))
+    }
+
+    /// Returns a boolean value for whether the `u` flag is present in `JsRegExp` flags
+    #[inline]
+    pub fn unicode(&self, context: &mut Context) -> JsResult<bool> {
+        RegExp::get_unicode(&self.inner.clone().into(), &[], context)
+            .map(|v| v.as_boolean().expect("value must be a bool"))
+    }
+
+    /// Returns a boolean value for whether the `y` flag is present in `JsRegExp` flags
+    #[inline]
+    pub fn sticky(&self, context: &mut Context) -> JsResult<bool> {
+        RegExp::get_sticky(&self.inner.clone().into(), &[], context)
+            .map(|v| v.as_boolean().expect("value must be a bool"))
+    }
+
+    /// Returns the flags of `JsRegExp` as a string
+    /// ```
+    /// # use boa_engine::{
+    /// #  object::builtins::JsRegExp,
+    /// #  Context, JsValue,
+    /// # };
+    /// # let context = &mut Context::default();
+    /// let regexp = JsRegExp::new("foo", "gi", context).unwrap();
+    ///
+    /// let flags = regexp.flags(context).unwrap();
+    /// assert_eq!(flags, String::from("gi"));
+    /// ```
+    #[inline]
+    pub fn flags(&self, context: &mut Context) -> JsResult<String> {
+        RegExp::get_flags(&self.inner.clone().into(), &[], context).map(|v| {
+            v.as_string()
+                .expect("value must be string")
+                .to_std_string()
+                .expect("flags must be a valid string")
+        })
+    }
+
+    /// Returns the source pattern of `JsRegExp` as a string
+    /// ```
+    /// # use boa_engine::{
+    /// #  object::builtins::JsRegExp,
+    /// #  Context, JsValue,
+    /// # };
+    /// # let context = &mut Context::default();
+    /// let regexp = JsRegExp::new("foo", "gi", context).unwrap();
+    ///
+    /// let src = regexp.source(context).unwrap();
+    /// assert_eq!(src, String::from("foo"));
+    /// ```
+    #[inline]
+    pub fn source(&self, context: &mut Context) -> JsResult<String> {
+        RegExp::get_source(&self.inner.clone().into(), &[], context).map(|v| {
+            v.as_string()
+                .expect("value must be string")
+                .to_std_string()
+                .expect("source must be a valid string")
+        })
+    }
+
+    /// Executes a search for a match between `JsRegExp` and the provided string
+    /// ```
+    /// # use boa_engine::{
+    /// #  object::builtins::JsRegExp,
+    /// #  Context, JsValue,
+    /// # };
+    /// # let context = &mut Context::default();
+    /// let regexp = JsRegExp::new("foo", "gi", context).unwrap();
+    ///
+    /// let test_result = regexp.test("football", context).unwrap();
+    /// assert!(test_result);
+    /// ```
+    #[inline]
+    pub fn test<S>(&self, search_string: S, context: &mut Context) -> JsResult<bool>
+    where
+        S: Into<JsValue>,
+    {
+        RegExp::test(&self.inner.clone().into(), &[search_string.into()], context)
+            .map(|v| v.as_boolean().expect("value must be a bool"))
+    }
+
+    /// Executes a search for a match in a specified string
+    ///
+    /// Returns a `JsArray` containing matched value and updates the `lastIndex` property, or `None`
+    #[inline]
+    pub fn exec<S>(&self, search_string: S, context: &mut Context) -> JsResult<Option<JsArray>>
+    where
+        S: Into<JsValue>,
+    {
+        RegExp::exec(&self.inner.clone().into(), &[search_string.into()], context).map(|v| {
+            if v.is_null() {
+                None
+            } else {
+                Some(
+                    JsArray::from_object(
+                        v.to_object(context).expect("v must be an array"),
+                        context,
+                    )
+                    .expect("from_object must not fail if v is an array object"),
+                )
+            }
+        })
+    }
+
+    /// Return a string representing the regular expression.
+    /// ```
+    /// # use boa_engine::{
+    /// #  object::builtins::JsRegExp,
+    /// #  Context, JsValue,
+    /// # };
+    /// # let context = &mut Context::default();
+    /// let regexp = JsRegExp::new("foo", "gi", context).unwrap();
+    ///
+    /// let to_string = regexp.to_string(context).unwrap();
+    /// assert_eq!(to_string, String::from("/foo/gi"));
+    /// ```
+    #[inline]
+    pub fn to_string(&self, context: &mut Context) -> JsResult<String> {
+        RegExp::to_string(&self.inner.clone().into(), &[], context).map(|v| {
+            v.as_string()
+                .expect("value must be a string")
+                .to_std_string()
+                .expect("to_string value must be a valid string")
+        })
+    }
+}
+
+impl From<JsRegExp> for JsObject {
+    #[inline]
+    fn from(o: JsRegExp) -> Self {
+        o.inner.clone()
+    }
+}
+
+impl From<JsRegExp> for JsValue {
+    #[inline]
+    fn from(o: JsRegExp) -> Self {
+        o.inner.clone().into()
+    }
+}
+
+impl Deref for JsRegExp {
+    type Target = JsObject;
+
+    #[inline]
+    fn deref(&self) -> &Self::Target {
+        &self.inner
+    }
+}
+
+impl JsObjectType for JsRegExp {}

boa_engine/src/object/builtins/mod.rs

@@ -7,6 +7,7 @@ mod jsfunction;
 mod jsmap;
 mod jsmap_iterator;
 pub(crate) mod jsproxy;
+mod jsregexp;
 mod jsset;
 mod jsset_iterator;
 mod jstypedarray;
@@ -18,6 +19,7 @@ pub use jsfunction::*;
 pub use jsmap::*;
 pub use jsmap_iterator::*;
 pub use jsproxy::{JsProxy, JsRevocableProxy};
+pub use jsregexp::JsRegExp;
 pub use jsset::*;
 pub use jsset_iterator::*;
 pub use jstypedarray::*;

boa_examples/src/bin/jsregexp.rs

@@ -0,0 +1,21 @@
+use boa_engine::{object::builtins::JsRegExp, Context, JsResult};
+
+fn main() -> JsResult<()> {
+    let context = &mut Context::default();
+
+    let regexp = JsRegExp::new("foo", "gi", context)?;
+
+    let test_result = regexp.test("football", context)?;
+    assert!(test_result);
+
+    let flags = regexp.flags(context)?;
+    assert_eq!(flags, String::from("gi"));
+
+    let src = regexp.source(context)?;
+    assert_eq!(src, String::from("foo"));
+
+    let to_string = regexp.to_string(context)?;
+    assert_eq!(to_string, String::from("/foo/gi"));
+
+    Ok(())
+}