Respect Rust 1.53 (#1352)

* Style: Don't repeat code at end of if

Respecting lint clippy::branches_sharing_code

* Refactor: Introduce BigInt::is_zero, reduce allocations

* Refactor: Use self for "converting" date methods

Respecting the wrong_self_conversion lint

* Style: rustfmt

* Test: Prepare Array.prototype.concat test

boa/src/builtins/array/tests.rs

@@ -118,42 +118,42 @@ fn of() {
 }
 
 #[ignore]
+#[test]
 fn concat() {
-    //TODO: array display formatter
     let mut context = Context::new();
     let init = r#"
-    var empty = new Array();
-    var one = new Array(1);
+    var empty = [];
+    var one = [1];
     "#;
     context.eval(init).unwrap();
     // Empty ++ Empty
     let ee = context
         .eval("empty.concat(empty)")
         .unwrap()
-        .to_string(&mut context)
-        .unwrap();
+        .display()
+        .to_string();
     assert_eq!(ee, "[]");
     // Empty ++ NonEmpty
     let en = context
         .eval("empty.concat(one)")
         .unwrap()
-        .to_string(&mut context)
-        .unwrap();
-    assert_eq!(en, "[a]");
+        .display()
+        .to_string();
+    assert_eq!(en, "[ 1 ]");
     // NonEmpty ++ Empty
     let ne = context
         .eval("one.concat(empty)")
         .unwrap()
-        .to_string(&mut context)
-        .unwrap();
-    assert_eq!(ne, "a.b.c");
+        .display()
+        .to_string();
+    assert_eq!(ne, "[ 1 ]");
     // NonEmpty ++ NonEmpty
     let nn = context
         .eval("one.concat(one)")
         .unwrap()
-        .to_string(&mut context)
-        .unwrap();
-    assert_eq!(nn, "a.b.c");
+        .display()
+        .to_string();
+    assert_eq!(nn, "[ 1, 1 ]");
 }
 
 #[test]

boa/src/builtins/bigint/mod.rs

@@ -237,6 +237,15 @@ impl BigInt {
             bits,
         ))
     }
+
+    /// helper function for checking if the BigInt represents 0
+    ///
+    /// creating BigInts requires an allocation and for a few operations we need to know if the
+    /// inner value is 0, this solves that situation
+    pub(crate) fn is_zero(&self) -> bool {
+        use num_traits::Zero;
+        self.0.is_zero()
+    }
 }
 
 impl Finalize for BigInt {}

boa/src/builtins/date/mod.rs

@@ -217,7 +217,7 @@ impl Date {
     /// Converts the `Date` to a local `DateTime`.
     ///
     /// If the `Date` is invalid (i.e. NAN), this function will return `None`.
-    pub fn to_local(&self) -> Option<DateTime<Local>> {
+    pub fn to_local(self) -> Option<DateTime<Local>> {
         self.0
             .map(|utc| Local::now().timezone().from_utc_datetime(&utc))
     }
@@ -225,7 +225,7 @@ impl Date {
     /// Converts the `Date` to a UTC `DateTime`.
     ///
     /// If the `Date` is invalid (i.e. NAN), this function will return `None`.
-    pub fn to_utc(&self) -> Option<DateTime<Utc>> {
+    pub fn to_utc(self) -> Option<DateTime<Utc>> {
         self.0
             .map(|utc| Utc::now().timezone().from_utc_datetime(&utc))
     }
@@ -1203,7 +1203,7 @@ impl Date {
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-date.prototype.todatestring
     /// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toDateString
-    pub fn to_date_string(&self) -> String {
+    pub fn to_date_string(self) -> String {
         self.to_local()
             .map(|date_time| date_time.format("%a %b %d %Y").to_string())
             .unwrap_or_else(|| "Invalid Date".to_string())
@@ -1219,7 +1219,7 @@ impl Date {
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-date.prototype.togmtstring
     /// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toGMTString
-    pub fn to_gmt_string(&self) -> String {
+    pub fn to_gmt_string(self) -> String {
         self.to_utc_string()
     }
 
@@ -1235,7 +1235,7 @@ impl Date {
     /// [iso8601]: http://en.wikipedia.org/wiki/ISO_8601
     /// [spec]: https://tc39.es/ecma262/#sec-date.prototype.toisostring
     /// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString
-    pub fn to_iso_string(&self) -> String {
+    pub fn to_iso_string(self) -> String {
         self.to_utc()
             // RFC 3389 uses +0.00 for UTC, where JS expects Z, so we can't use the built-in chrono function.
             .map(|f| f.format("%Y-%m-%dT%H:%M:%S.%3fZ").to_string())
@@ -1252,7 +1252,7 @@ impl Date {
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-date.prototype.tojson
     /// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toJSON
-    pub fn to_json(&self) -> String {
+    pub fn to_json(self) -> String {
         self.to_iso_string()
     }
 
@@ -1267,7 +1267,7 @@ impl Date {
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-date.prototype.totimestring
     /// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toTimeString
-    pub fn to_time_string(&self) -> String {
+    pub fn to_time_string(self) -> String {
         self.to_local()
             .map(|date_time| date_time.format("%H:%M:%S GMT%:z").to_string())
             .unwrap_or_else(|| "Invalid Date".to_string())
@@ -1283,7 +1283,7 @@ impl Date {
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-date.prototype.toutcstring
     /// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toUTCString
-    pub fn to_utc_string(&self) -> String {
+    pub fn to_utc_string(self) -> String {
         self.to_utc()
             .map(|date_time| date_time.format("%a, %d %b %Y %H:%M:%S GMT").to_string())
             .unwrap_or_else(|| "Invalid Date".to_string())

boa/src/builtins/number/mod.rs

@@ -564,7 +564,6 @@ impl Number {
                             //              CHECK_EQ('.', buffer[fraction_cursor]);
                             // Carry over to the integer part.
                             integer += 1.;
-                            break;
                         } else {
                             let c: u8 = frac_buf[fraction_cursor];
                             // Reconstruct digit.
@@ -575,8 +574,8 @@ impl Number {
                             frac_buf[fraction_cursor] =
                                 std::char::from_digit(digit_0 + 1, radix as u32).unwrap() as u8;
                             fraction_cursor += 1;
-                            break;
                         }
+                        break;
                     }
                     break;
                 }

boa/src/syntax/lexer/string.rs

@@ -127,7 +127,12 @@ impl StringLiteral {
                     let _timer = BoaProfiler::global()
                         .start_event("StringLiteral - escape sequence", "Lexing");
 
-                    if let Some(escape_value) = Self::take_escape_sequence_or_line_continuation(cursor, ch_start_pos, is_strict_mode, false)? {
+                    if let Some(escape_value) = Self::take_escape_sequence_or_line_continuation(
+                        cursor,
+                        ch_start_pos,
+                        is_strict_mode,
+                        false,
+                    )? {
                         buf.push_code_point(escape_value);
                     }
                 }

boa/src/syntax/parser/cursor/buffered_lexer/mod.rs

@@ -163,18 +163,15 @@ where
         }
 
         if let Some(ref token) = self.peeked[self.read_index] {
-            let tok = if !skip_line_terminators || token.kind() != &TokenKind::LineTerminator {
-                self.peeked[self.read_index].take()
-            } else {
+            if skip_line_terminators && token.kind() == &TokenKind::LineTerminator {
                 // We only store 1 contiguous line terminator, so if the one at `self.read_index`
                 // was a line terminator, we know that the next won't be one.
                 self.read_index = (self.read_index + 1) % PEEK_BUF_SIZE;
                 if self.read_index == self.write_index {
                     self.fill()?;
                 }
-
-                self.peeked[self.read_index].take()
-            };
+            }
+            let tok = self.peeked[self.read_index].take();
             self.read_index = (self.read_index + 1) % PEEK_BUF_SIZE;
 
             Ok(tok)
@@ -220,21 +217,16 @@ where
             }
 
             if let Some(ref token) = self.peeked[read_index] {
-                if !skip_line_terminators || token.kind() != &TokenKind::LineTerminator {
-                    if count == skip_n {
-                        break self.peeked[read_index].as_ref();
-                    }
-                } else {
+                if skip_line_terminators && token.kind() == &TokenKind::LineTerminator {
                     read_index = (read_index + 1) % PEEK_BUF_SIZE;
                     // We only store 1 contiguous line terminator, so if the one at `self.read_index`
                     // was a line terminator, we know that the next won't be one.
                     if read_index == self.write_index {
                         self.fill()?;
                     }
-
-                    if count == skip_n {
-                        break self.peeked[read_index].as_ref();
-                    }
+                }
+                if count == skip_n {
+                    break self.peeked[read_index].as_ref();
                 }
             } else {
                 break None;

boa/src/value/operations.rs

@@ -110,7 +110,7 @@ impl Value {
             (Self::Rational(x), Self::Integer(y)) => Self::rational(x / f64::from(*y)),
 
             (Self::BigInt(ref a), Self::BigInt(ref b)) => {
-                if *b.as_inner() == BigInt::from(0) {
+                if b.as_inner().is_zero() {
                     return context.throw_range_error("BigInt division by zero");
                 }
                 Self::bigint(a.as_inner().clone() / b.as_inner().clone())
@@ -120,7 +120,7 @@ impl Value {
             (_, _) => match (self.to_numeric(context)?, other.to_numeric(context)?) {
                 (Numeric::Number(a), Numeric::Number(b)) => Self::rational(a / b),
                 (Numeric::BigInt(ref a), Numeric::BigInt(ref b)) => {
-                    if *b.as_inner() == BigInt::from(0) {
+                    if b.as_inner().is_zero() {
                         return context.throw_range_error("BigInt division by zero");
                     }
                     Self::bigint(a.as_inner().clone() / b.as_inner().clone())
@@ -150,7 +150,7 @@ impl Value {
             (Self::Rational(x), Self::Integer(y)) => Self::rational(x % f64::from(*y)),
 
             (Self::BigInt(ref a), Self::BigInt(ref b)) => {
-                if *b.as_inner() == BigInt::from(0) {
+                if b.as_inner().is_zero() {
                     return context.throw_range_error("BigInt division by zero");
                 }
                 Self::bigint(a.as_inner().clone() % b.as_inner().clone())