feat(codegen): minify more whitespace (#8089)

crates/oxc_codegen/src/gen.rs

@@ -396,7 +396,7 @@ impl Gen for ForInStatement<'_> {
         p.print_soft_space();
         p.print_space_before_identifier();
         p.print_str("in");
-        p.print_hard_space();
+        p.print_soft_space();
         p.print_expression(&self.right);
         p.print_ascii_byte(b')');
         p.print_body(&self.body, false, ctx);
@@ -503,7 +503,7 @@ impl Gen for ContinueStatement<'_> {
         p.print_indent();
         p.print_str("continue");
         if let Some(label) = &self.label {
-            p.print_hard_space();
+            p.print_soft_space();
             label.print(p, ctx);
         }
         p.print_semicolon_after_statement();
@@ -516,7 +516,7 @@ impl Gen for BreakStatement<'_> {
         p.print_indent();
         p.print_str("break");
         if let Some(label) = &self.label {
-            p.print_hard_space();
+            p.print_soft_space();
             label.print(p, ctx);
         }
         p.print_semicolon_after_statement();
@@ -800,14 +800,17 @@ impl Gen for FormalParameter<'_> {
     fn gen(&self, p: &mut Codegen, ctx: Context) {
         for decorator in &self.decorators {
             decorator.print(p, ctx);
-            p.print_hard_space();
+            p.print_soft_space();
         }
         if let Some(accessibility) = self.accessibility {
+            p.print_space_before_identifier();
             p.print_str(accessibility.as_str());
-            p.print_hard_space();
+            p.print_soft_space();
         }
         if self.readonly {
-            p.print_str("readonly ");
+            p.print_space_before_identifier();
+            p.print_str("readonly");
+            p.print_soft_space();
         }
         self.pattern.print(p, ctx);
     }
@@ -1237,6 +1240,7 @@ impl Gen for BindingIdentifier<'_> {
 
 impl Gen for LabelIdentifier<'_> {
     fn gen(&self, p: &mut Codegen, _ctx: Context) {
+        p.print_space_before_identifier();
         p.add_source_mapping_for_name(self.span, &self.name);
         p.print_str(self.name.as_str());
     }
@@ -1843,7 +1847,7 @@ impl GenExpr for UnaryExpression<'_> {
             if self.operator.is_keyword() {
                 p.print_space_before_identifier();
                 p.print_str(operator);
-                p.print_hard_space();
+                p.print_soft_space();
             } else {
                 p.print_space_before_operator(self.operator.into());
                 p.print_str(operator);
@@ -2089,21 +2093,33 @@ impl Gen for AssignmentTargetPropertyIdentifier<'_> {
 
 impl Gen for AssignmentTargetPropertyProperty<'_> {
     fn gen(&self, p: &mut Codegen, ctx: Context) {
-        match &self.name {
-            PropertyKey::StaticIdentifier(ident) => {
-                ident.print(p, ctx);
-            }
-            PropertyKey::PrivateIdentifier(ident) => {
-                ident.print(p, ctx);
-            }
-            key @ match_expression!(PropertyKey) => {
-                p.print_ascii_byte(b'[');
-                key.to_expression().print_expr(p, Precedence::Comma, Context::empty());
-                p.print_ascii_byte(b']');
+        let omit_key = if p.options.minify {
+            let key_name = match &self.name {
+                PropertyKey::StaticIdentifier(ident) => Some(&ident.name),
+                _ => None,
+            };
+            let value_name = self.binding.name();
+            key_name.is_some() && value_name.is_some() && key_name == value_name.as_ref()
+        } else {
+            false
+        };
+        if !omit_key {
+            match &self.name {
+                PropertyKey::StaticIdentifier(ident) => {
+                    ident.print(p, ctx);
+                }
+                PropertyKey::PrivateIdentifier(ident) => {
+                    ident.print(p, ctx);
+                }
+                key @ match_expression!(PropertyKey) => {
+                    p.print_ascii_byte(b'[');
+                    key.to_expression().print_expr(p, Precedence::Comma, Context::empty());
+                    p.print_ascii_byte(b']');
+                }
             }
+            p.print_colon();
+            p.print_soft_space();
         }
-        p.print_colon();
-        p.print_soft_space();
         self.binding.print(p, ctx);
     }
 }

crates/oxc_codegen/tests/integration/unit.rs

@@ -37,7 +37,7 @@ fn expr() {
     test_minify_same("await import(\"\");");
 
     test("delete 2e308", "delete (0, Infinity);\n");
-    test_minify("delete 2e308", "delete (1/0);");
+    test_minify("delete 2e308", "delete(1/0);");
 }
 
 #[test]
@@ -154,7 +154,7 @@ fn assignment() {
     test_minify("a /= () => {}", "a/=()=>{};");
     test_minify("a %= async () => {}", "a%=async()=>{};");
     test_minify("a -= (1, 2)", "a-=(1,2);");
-    test_minify("a >>= b >>= c", "a>>=b>>=c;");
+    test_minify("({ x: x = flag1 = true } = {})", "({x=flag1=true}={});");
 }
 
 #[test]

tasks/minsize/minsize.snap

@@ -13,15 +13,15 @@ Original   | minified   | minified   | gzip       | gzip       | Fixture
 
 555.77 kB  | 276.06 kB  | 270.13 kB  | 91.14 kB   | 90.80 kB   | d3.js     
 
-1.01 MB    | 466.83 kB  | 458.89 kB  | 126.74 kB  | 126.71 kB  | bundle.min.js
+1.01 MB    | 466.82 kB  | 458.89 kB  | 126.74 kB  | 126.71 kB  | bundle.min.js
 
 1.25 MB    | 661.47 kB  | 646.76 kB  | 163.94 kB  | 163.73 kB  | three.js  
 
 2.14 MB    | 740.44 kB  | 724.14 kB  | 181.35 kB  | 181.07 kB  | victory.js
 
 3.20 MB    | 1.02 MB    | 1.01 MB    | 332.00 kB  | 331.56 kB  | echarts.js
 
-6.69 MB    | 2.39 MB    | 2.31 MB    | 495.62 kB  | 488.28 kB  | antd.js   
+6.69 MB    | 2.39 MB    | 2.31 MB    | 495.63 kB  | 488.28 kB  | antd.js   
 
-10.95 MB   | 3.54 MB    | 3.49 MB    | 909.70 kB  | 915.50 kB  | typescript.js
+10.95 MB   | 3.54 MB    | 3.49 MB    | 909.72 kB  | 915.50 kB  | typescript.js