feat(es/minifier): Turn Array/Object calls into literals (#4947)

crates/swc/tests/tsc-references/ExportVariableOfGenericTypeWithInaccessibleTypeAsTypeArgument_es2015.2.minified.js

@@ -1,5 +1,5 @@
 var A;
 !function(A1) {
     var beez;
-    A1.beez2 = Array(), A1.beez = beez;
+    A1.beez2 = [], A1.beez = beez;
 }(A || (A = {}));

crates/swc/tests/tsc-references/ExportVariableOfGenericTypeWithInaccessibleTypeAsTypeArgument_es5.2.minified.js

@@ -5,5 +5,5 @@ import _class_call_check from "@swc/helpers/lib/_class_call_check.js";
         "use strict";
         _class_call_check(this, B);
     };
-    A1.beez2 = Array(), A1.beez = beez;
+    A1.beez2 = [], A1.beez = beez;
 }(A || (A = {}));

crates/swc/tests/tsc-references/arrayLiterals2ES5_es5.1.normal.js

@@ -20,11 +20,13 @@ var a1 = [
 var a2 = [
     ,
     ,
+    , 
 ].concat(_to_consumable_array(a0), [
     "hello"
 ]);
 var a3 = [
     ,
+    , 
 ].concat(_to_consumable_array(a0));
 var a4 = [
     function() {

crates/swc/tests/tsc-references/arrayLiterals2ES5_es5.2.minified.js

@@ -9,10 +9,12 @@ var a0 = [
 [
     ,
     ,
+    , 
 ].concat(_to_consumable_array(a0), [
     "hello"
 ]), [
     ,
+    , 
 ].concat(_to_consumable_array(a0)), _to_consumable_array(a0).concat([
     , 
 ]);

crates/swc/tests/tsc-references/arrayLiterals2ES6_es5.1.normal.js

@@ -21,11 +21,13 @@ var a1 = [
 var a2 = [
     ,
     ,
+    , 
 ].concat(_to_consumable_array(a0), [
     "hello"
 ]);
 var a3 = [
     ,
+    , 
 ].concat(_to_consumable_array(a0));
 var a4 = [
     function() {

crates/swc/tests/tsc-references/arrayLiterals2ES6_es5.2.minified.js

@@ -8,10 +8,12 @@ var a0 = [
 ], a2 = [
     ,
     ,
+    , 
 ].concat(_to_consumable_array(a0), [
     "hello"
 ]), a3 = [
     ,
+    , 
 ].concat(_to_consumable_array(a0));
 _to_consumable_array(a0).concat([
     , 

crates/swc/tests/tsc-references/genericCallWithConstraintsTypeArgumentInference2_es2015.2.minified.js

@@ -1,2 +1,2 @@
 function foo(t) {}
-foo(1), foo(null), foo(new Object()), foo(1), foo(new Date());
+foo(1), foo(null), foo({}), foo(1), foo(new Date());

crates/swc/tests/tsc-references/genericCallWithConstraintsTypeArgumentInference2_es5.2.minified.js

@@ -1,2 +1,2 @@
 function foo(t) {}
-foo(1), foo(null), foo(new Object()), foo(1), foo(new Date());
+foo(1), foo(null), foo({}), foo(1), foo(new Date());

crates/swc/tests/tsc-references/genericCallWithGenericSignatureArguments3_es2015.2.minified.js

@@ -1,7 +1,7 @@
 var E, F, x;
 function foo(x, a, b) {}
 function foo2(x, a, b) {}
-foo('', (x)=>'', (x)=>null), foo('', (x)=>'', (x)=>null), foo('', (x)=>'', (x)=>''), foo(null, (x)=>'', (x)=>''), foo(null, (x)=>'', (x)=>''), foo(new Object(), (x)=>'', (x)=>''), function(E) {
+foo('', (x)=>'', (x)=>null), foo('', (x)=>'', (x)=>null), foo('', (x)=>'', (x)=>''), foo(null, (x)=>'', (x)=>''), foo(null, (x)=>'', (x)=>''), foo({}, (x)=>'', (x)=>''), function(E) {
     E[E.A = 0] = "A";
 }(E || (E = {})), function(F) {
     F[F.A = 0] = "A";

crates/swc/tests/tsc-references/genericCallWithGenericSignatureArguments3_es5.2.minified.js

@@ -21,7 +21,7 @@ foo("", function(x) {
     return "";
 }, function(x) {
     return "";
-}), foo(new Object(), function(x) {
+}), foo({}, function(x) {
     return "";
 }, function(x) {
     return "";

crates/swc/tests/tsc-references/parser15.4.4.14-9-2_es2015.2.minified.js

@@ -1,8 +1,25 @@
 runTestCase(function() {
-    var a = Array(!1, void 0, null, "0", {
-        toString: function() {
-            return 0;
-        }
-    }, -1.3333333333333, "str", -0, !0, 0, 1, 1, 0, !1, -4 / 3, -4 / 3);
+    var a = [
+        !1,
+        void 0,
+        null,
+        "0",
+        {
+            toString: function() {
+                return 0;
+            }
+        },
+        -1.3333333333333,
+        "str",
+        -0,
+        !0,
+        0,
+        1,
+        1,
+        0,
+        !1,
+        -4 / 3,
+        -4 / 3
+    ];
     if (14 === a.indexOf(-4 / 3) && 7 === a.indexOf(0) && 7 === a.indexOf(-0) && 10 === a.indexOf(1)) return !0;
 });

crates/swc/tests/tsc-references/parser15.4.4.14-9-2_es5.2.minified.js

@@ -1,8 +1,25 @@
 runTestCase(function() {
-    var a = Array(!1, void 0, null, "0", {
-        toString: function() {
-            return 0;
-        }
-    }, -1.3333333333333, "str", -0, !0, 0, 1, 1, 0, !1, -4 / 3, -4 / 3);
+    var a = [
+        !1,
+        void 0,
+        null,
+        "0",
+        {
+            toString: function() {
+                return 0;
+            }
+        },
+        -1.3333333333333,
+        "str",
+        -0,
+        !0,
+        0,
+        1,
+        1,
+        0,
+        !1,
+        -4 / 3,
+        -4 / 3
+    ];
     if (14 === a.indexOf(-4 / 3) && 7 === a.indexOf(0) && 7 === a.indexOf(-0) && 10 === a.indexOf(1)) return !0;
 });

crates/swc/tests/tsc-references/subtypingWithOptionalProperties_es2015.2.minified.js

@@ -1,4 +1,4 @@
 var r = {
-    s: new Object()
+    s: {}
 };
 r.s && r.s.toFixed();

crates/swc/tests/tsc-references/subtypingWithOptionalProperties_es5.2.minified.js

@@ -1,4 +1,4 @@
 var r = {
-    s: new Object()
+    s: {}
 };
 r.s && r.s.toFixed();

crates/swc_ecma_ast/src/list.rs

@@ -79,10 +79,11 @@ add_bitflags!(
         /// If the literal is empty, do not add spaces between braces.
         NoSpaceIfEmpty: 1 << 18,
         SingleElement: 1 << 19,
+        ForceTrailingComma: 1 << 20,
     },
     // Optimization.
     Values {
-        CanSkipTrailingComma: 1 << 20
+        CanSkipTrailingComma: 1 << 21
     },
     /// Precomputed Formats
     Values {

crates/swc_ecma_codegen/src/lib.rs

@@ -1835,11 +1835,12 @@ where
         srcmap!(node, true);
 
         punct!("[");
-        self.emit_list(
-            node.span(),
-            Some(&node.elems),
-            ListFormat::ArrayLiteralExpressionElements,
-        )?;
+        let mut format = ListFormat::ArrayLiteralExpressionElements;
+        if let Some(None) = node.elems.last() {
+            format |= ListFormat::ForceTrailingComma;
+        }
+
+        self.emit_list(node.span(), Some(&node.elems), format)?;
         punct!("]");
 
         srcmap!(node, false);
@@ -2224,25 +2225,26 @@ where
             }
 
             // Write a trailing comma, if requested.
-            let has_trailing_comma = format.contains(ListFormat::AllowTrailingComma) && {
-                if parent_node.is_dummy() {
-                    false
-                } else {
-                    match self.cm.span_to_snippet(parent_node) {
-                        Ok(snippet) => {
-                            if snippet.len() < 3 {
-                                false
-                            } else {
-                                let last_char = snippet.chars().last().unwrap();
-                                snippet[..snippet.len() - last_char.len_utf8()]
-                                    .trim()
-                                    .ends_with(',')
+            let has_trailing_comma = format.contains(ListFormat::ForceTrailingComma)
+                || format.contains(ListFormat::AllowTrailingComma) && {
+                    if parent_node.is_dummy() {
+                        false
+                    } else {
+                        match self.cm.span_to_snippet(parent_node) {
+                            Ok(snippet) => {
+                                if snippet.len() < 3 {
+                                    false
+                                } else {
+                                    let last_char = snippet.chars().last().unwrap();
+                                    snippet[..snippet.len() - last_char.len_utf8()]
+                                        .trim()
+                                        .ends_with(',')
+                                }
                             }
+                            _ => false,
                         }
-                        _ => false,
                     }
-                }
-            };
+                };
 
             if has_trailing_comma
                 && format.contains(ListFormat::CommaDelimited)

crates/swc_ecma_minifier/src/compress/optimize/mod.rs

@@ -1101,104 +1101,6 @@ where
         Some(e.take())
     }
 
-    /// `new RegExp("([Sap]+)", "ig")` => `/([Sap]+)/gi`
-    fn compress_regexp(&mut self, e: &mut Expr) {
-        let (span, args) = match e {
-            Expr::New(NewExpr {
-                span,
-                callee,
-                args: Some(args),
-                ..
-            })
-            | Expr::Call(CallExpr {
-                span,
-                callee: Callee::Expr(callee),
-                args,
-                ..
-            }) => match &**callee {
-                Expr::Ident(Ident {
-                    sym: js_word!("RegExp"),
-                    ..
-                }) => (*span, args),
-                _ => return,
-            },
-            _ => return,
-        };
-
-        if args.is_empty() || args.len() > 2 {
-            return;
-        }
-
-        // We aborts the method if arguments are not literals.
-        if args.iter().any(|v| {
-            v.spread.is_some()
-                || match &*v.expr {
-                    Expr::Lit(Lit::Str(s)) => {
-                        if s.value.contains(|c: char| {
-                            // whitelist
-                            !c.is_ascii_alphanumeric()
-                                && !matches!(c, '%' | '[' | ']' | '(' | ')' | '{' | '}' | '-' | '+')
-                        }) {
-                            return true;
-                        }
-                        if s.value.contains("\\\0") || s.value.contains('/') {
-                            return true;
-                        }
-
-                        false
-                    }
-                    _ => true,
-                }
-        }) {
-            return;
-        }
-
-        //
-        let pattern = args[0].expr.take();
-
-        let pattern = match *pattern {
-            Expr::Lit(Lit::Str(s)) => s.value,
-            _ => {
-                unreachable!()
-            }
-        };
-
-        if pattern.is_empty() {
-            // For some expressions `RegExp()` and `RegExp("")`
-            // Theoretically we can use `/(?:)/` to achieve shorter code
-            // But some browsers released in 2015 don't support them yet.
-            args[0].expr = pattern.into();
-            return;
-        }
-
-        let flags = args
-            .get_mut(1)
-            .map(|v| v.expr.take())
-            .map(|v| match *v {
-                Expr::Lit(Lit::Str(s)) => {
-                    assert!(s.value.is_ascii());
-
-                    let s = s.value.to_string();
-                    let mut bytes = s.into_bytes();
-                    bytes.sort_unstable();
-
-                    String::from_utf8(bytes).unwrap().into()
-                }
-                _ => {
-                    unreachable!()
-                }
-            })
-            .unwrap_or(js_word!(""));
-
-        report_change!("Converting call to RegExp into a regexp literal");
-        self.changed = true;
-        *e = Expr::Lit(Lit::Regex(Regex {
-            span,
-            exp: pattern,
-            flags,
-        }))
-    }
-
     fn merge_var_decls(&mut self, stmts: &mut Vec<Stmt>) {
         if !self.options.join_vars && !self.options.hoist_vars {
             return;
@@ -1739,8 +1641,6 @@ where
 
         self.drop_unused_assignments(e);
 
-        self.compress_regexp(e);
-
         self.compress_lits(e);
 
         self.compress_typeofs(e);