Rewrite some patterns with let-else and ok_or_else (#2404)

This Pull Request updates the codebase to the newest version of rustc (1.65.0).

It changes the following:

- Bumps `rust-version` to 1.65.0.
- Rewrites some snippets to use the new let else, ok_or_else and some other utils.
- Removes the `rustdoc::missing_doc_code_examples` allow lint from our codebase. (Context: rust-lang/rust#101732)

Author: jedel1043

Cargo.toml

@@ -16,7 +16,7 @@ members = [
 [workspace.package]
 edition = "2021"
 version = "0.16.0"
-rust-version = "1.64"
+rust-version = "1.65"
 authors = ["boa-dev"]
 repository = "https://github.com/boa-dev/boa"
 license = "Unlicense/MIT"

boa_ast/src/lib.rs

@@ -49,11 +49,7 @@
     nonstandard_style,
     missing_docs
 )]
-#![allow(
-    clippy::module_name_repetitions,
-    clippy::too_many_lines,
-    rustdoc::missing_doc_code_examples
-)]
+#![allow(clippy::module_name_repetitions, clippy::too_many_lines)]
 
 mod position;
 mod punctuator;

boa_engine/src/bigint.rs

@@ -149,13 +149,10 @@ impl JsBigInt {
 
     #[inline]
     pub fn pow(x: &Self, y: &Self) -> JsResult<Self> {
-        let y = if let Some(y) = y.inner.to_biguint() {
-            y
-        } else {
-            return Err(JsNativeError::range()
-                .with_message("BigInt negative exponent")
-                .into());
-        };
+        let y = y
+            .inner
+            .to_biguint()
+            .ok_or_else(|| JsNativeError::range().with_message("BigInt negative exponent"))?;
 
         let num_bits = (x.inner.bits() as f64
             * y.to_f64().expect("Unable to convert from BigUInt to f64"))

boa_engine/src/builtins/array/mod.rs

@@ -300,9 +300,7 @@ impl Array {
     /// by `Array.prototype.concat`.
     fn is_concat_spreadable(o: &JsValue, context: &mut Context) -> JsResult<bool> {
         // 1. If Type(O) is not Object, return false.
-        let o = if let Some(o) = o.as_object() {
-            o
-        } else {
+        let Some(o) = o.as_object() else {
             return Ok(false);
         };
 
@@ -461,9 +459,7 @@ impl Array {
                 let next = iterator_record.step(context)?;
 
                 // iv. If next is false, then
-                let next = if let Some(next) = next {
-                    next
-                } else {
+                let Some(next) = next else {
                     // 1. Perform ? Set(A, "length", 𝔽(k), true).
                     a.set("length", k, true, context)?;
 

boa_engine/src/builtins/array_buffer/mod.rs

@@ -148,33 +148,25 @@ impl ArrayBuffer {
     ) -> JsResult<JsValue> {
         // 1. Let O be the this value.
         // 2. Perform ? RequireInternalSlot(O, [[ArrayBufferData]]).
-        let obj = if let Some(obj) = this.as_object() {
-            obj
-        } else {
-            return Err(JsNativeError::typ()
-                .with_message("ArrayBuffer.byteLength called with non-object value")
-                .into());
-        };
+        let obj = this.as_object().ok_or_else(|| {
+            JsNativeError::typ().with_message("ArrayBuffer.byteLength called with non-object value")
+        })?;
         let obj = obj.borrow();
-        let o = if let Some(o) = obj.as_array_buffer() {
-            o
-        } else {
-            return Err(JsNativeError::typ()
-                .with_message("ArrayBuffer.byteLength called with invalid object")
-                .into());
-        };
+        let buf = obj.as_array_buffer().ok_or_else(|| {
+            JsNativeError::typ().with_message("ArrayBuffer.byteLength called with invalid object")
+        })?;
 
         // TODO: Shared Array Buffer
         // 3. If IsSharedArrayBuffer(O) is true, throw a TypeError exception.
 
         // 4. If IsDetachedBuffer(O) is true, return +0𝔽.
-        if Self::is_detached_buffer(o) {
+        if Self::is_detached_buffer(buf) {
             return Ok(0.into());
         }
 
         // 5. Let length be O.[[ArrayBufferByteLength]].
         // 6. Return 𝔽(length).
-        Ok(o.array_buffer_byte_length.into())
+        Ok(buf.array_buffer_byte_length.into())
     }
 
     /// `25.1.5.3 ArrayBuffer.prototype.slice ( start, end )`
@@ -186,34 +178,26 @@ impl ArrayBuffer {
     fn slice(this: &JsValue, args: &[JsValue], context: &mut Context) -> JsResult<JsValue> {
         // 1. Let O be the this value.
         // 2. Perform ? RequireInternalSlot(O, [[ArrayBufferData]]).
-        let obj = if let Some(obj) = this.as_object() {
-            obj
-        } else {
-            return Err(JsNativeError::typ()
-                .with_message("ArrayBuffer.slice called with non-object value")
-                .into());
-        };
+        let obj = this.as_object().ok_or_else(|| {
+            JsNativeError::typ().with_message("ArrayBuffer.slice called with non-object value")
+        })?;
         let obj_borrow = obj.borrow();
-        let o = if let Some(o) = obj_borrow.as_array_buffer() {
-            o
-        } else {
-            return Err(JsNativeError::typ()
-                .with_message("ArrayBuffer.slice called with invalid object")
-                .into());
-        };
+        let buf = obj_borrow.as_array_buffer().ok_or_else(|| {
+            JsNativeError::typ().with_message("ArrayBuffer.slice called with invalid object")
+        })?;
 
         // TODO: Shared Array Buffer
         // 3. If IsSharedArrayBuffer(O) is true, throw a TypeError exception.
 
         // 4. If IsDetachedBuffer(O) is true, throw a TypeError exception.
-        if Self::is_detached_buffer(o) {
+        if Self::is_detached_buffer(buf) {
             return Err(JsNativeError::typ()
                 .with_message("ArrayBuffer.slice called with detached buffer")
                 .into());
         }
 
         // 5. Let len be O.[[ArrayBufferByteLength]].
-        let len = o.array_buffer_byte_length as i64;
+        let len = buf.array_buffer_byte_length as i64;
 
         // 6. Let relativeStart be ? ToIntegerOrInfinity(start).
         let relative_start = args.get_or_undefined(0).to_integer_or_infinity(context)?;
@@ -298,14 +282,14 @@ impl ArrayBuffer {
 
             // 22. NOTE: Side-effects of the above steps may have detached O.
             // 23. If IsDetachedBuffer(O) is true, throw a TypeError exception.
-            if Self::is_detached_buffer(o) {
+            if Self::is_detached_buffer(buf) {
                 return Err(JsNativeError::typ()
                     .with_message("ArrayBuffer detached while ArrayBuffer.slice was running")
                     .into());
             }
 
             // 24. Let fromBuf be O.[[ArrayBufferData]].
-            let from_buf = o
+            let from_buf = buf
                 .array_buffer_data
                 .as_ref()
                 .expect("ArrayBuffer cannot be detached here");
@@ -389,13 +373,9 @@ impl ArrayBuffer {
 
         // 2. If IsDetachedBuffer(srcBuffer) is true, throw a TypeError exception.
         // 3. Let srcBlock be srcBuffer.[[ArrayBufferData]].
-        let src_block = if let Some(b) = &self.array_buffer_data {
-            b
-        } else {
-            return Err(JsNativeError::syntax()
-                .with_message("Cannot clone detached array buffer")
-                .into());
-        };
+        let src_block = self.array_buffer_data.as_deref().ok_or_else(|| {
+            JsNativeError::syntax().with_message("Cannot clone detached array buffer")
+        })?;
 
         {
             // 4. Let targetBlock be targetBuffer.[[ArrayBufferData]].