fix(minifier): skip Object.defineProperty(exports, ...) for cjs-module-lexer

crates/oxc_minifier/src/compressor/mod.rs

@@ -53,6 +53,16 @@ impl<'a> Compressor<'a> {
         self.ast.expression_binary(SPAN, left, BinaryOperator::Division, right)
     }
 
+    /// Test `Object.defineProperty(exports, ...)`
+    fn is_object_define_property_exports(expr: &Expression<'a>) -> bool {
+        let Expression::CallExpression(call_expr) = expr else { return false };
+        let Some(Argument::Identifier(ident)) = call_expr.arguments.first() else { return false };
+        if ident.name != "exports" {
+            return false;
+        }
+        call_expr.callee.is_specific_member_access("Object", "defineProperty")
+    }
+
     /* Statements */
 
     /// Remove block from single line blocks
@@ -345,6 +355,10 @@ impl<'a> VisitMut<'a> for Compressor<'a> {
     }
 
     fn visit_expression(&mut self, expr: &mut Expression<'a>) {
+        // Bail cjs `Object.defineProperty(exports, ...)`
+        if Self::is_object_define_property_exports(expr) {
+            return;
+        }
         walk_mut::walk_expression(self, expr);
         self.compress_console(expr);
         self.folder.fold_expression(expr);

crates/oxc_minifier/tests/mod.rs

@@ -6,11 +6,20 @@ mod oxc;
 // mod terser;
 
 use oxc_allocator::Allocator;
-use oxc_codegen::{CodegenOptions, WhitespaceRemover};
+use oxc_codegen::{CodeGenerator, CodegenOptions};
 use oxc_minifier::{CompressOptions, Minifier, MinifierOptions};
 use oxc_parser::Parser;
 use oxc_span::SourceType;
 
+fn codegen(source_text: &str, source_type: SourceType) -> String {
+    let allocator = Allocator::default();
+    let ret = Parser::new(&allocator, source_text, source_type).parse();
+    CodeGenerator::new()
+        .with_options(CodegenOptions { single_quote: true })
+        .build(&ret.program)
+        .source_text
+}
+
 pub(crate) fn minify(
     source_text: &str,
     source_type: SourceType,
@@ -20,7 +29,7 @@ pub(crate) fn minify(
     let ret = Parser::new(&allocator, source_text, source_type).parse();
     let program = allocator.alloc(ret.program);
     Minifier::new(options).build(&allocator, program);
-    WhitespaceRemover::new()
+    CodeGenerator::new()
         .with_options(CodegenOptions { single_quote: true })
         .build(program)
         .source_text
@@ -34,6 +43,7 @@ pub(crate) fn test(source_text: &str, expected: &str) {
 pub(crate) fn test_with_options(source_text: &str, expected: &str, options: MinifierOptions) {
     let source_type = SourceType::default();
     let minified = minify(source_text, source_type, options);
+    let expected = codegen(expected, source_type);
     assert_eq!(expected, minified, "for source {source_text}");
 }
 

crates/oxc_minifier/tests/oxc/booleans.rs

@@ -0,0 +1,15 @@
+use crate::test_same;
+
+#[test]
+fn cjs() {
+    // Export is undefined when `enumerable` is "!0".
+    // https://github.com/nodejs/cjs-module-lexer/issues/64
+    test_same(
+        "Object.defineProperty(exports, 'ConnectableObservable', {
+          enumerable: true,
+          get: function() {
+            return ConnectableObservable_1.ConnectableObservable;
+          }
+        });",
+    );
+}

crates/oxc_minifier/tests/oxc/mod.rs

@@ -1,5 +1,6 @@
 mod code_removal;
 mod folding;
 // mod precedence;
+mod booleans;
 mod remove_dead_code;
 mod replace_global_defines;

crates/oxc_minifier/tests/snapshots/addition_folding.snap

@@ -6,82 +6,104 @@ expression: snapshot
 let x = 1 + 1
 
 =================================== MINIFIED ===================================
-let x=2
+let x = 2;
+
 
 ==================================== SOURCE ====================================
 function foo() { return 1 + 1; }
 
 =================================== MINIFIED ===================================
-function foo(){return 2}
+function foo() {
+	return 2;
+}
+
 
 ==================================== SOURCE ====================================
 '' + true
 
 =================================== MINIFIED ===================================
-;'true'
+;
+'true';
+
 
 ==================================== SOURCE ====================================
 '' + false
 
 =================================== MINIFIED ===================================
-;'false'
+;
+'false';
+
 
 ==================================== SOURCE ====================================
 '' + null
 
 =================================== MINIFIED ===================================
-;'null'
+;
+'null';
+
 
 ==================================== SOURCE ====================================
 false + null
 
 =================================== MINIFIED ===================================
-!1+null
+!1 + null;
+
 
 ==================================== SOURCE ====================================
 '1' + '1'
 
 =================================== MINIFIED ===================================
-;'11'
+;
+'11';
+
 
 ==================================== SOURCE ====================================
 NaN + NaN
 
 =================================== MINIFIED ===================================
-NaN+NaN
+NaN + NaN;
+
 
 ==================================== SOURCE ====================================
 '' + NaN
 
 =================================== MINIFIED ===================================
-;'NaN'
+;
+'NaN';
+
 
 ==================================== SOURCE ====================================
 let x = 1; let y = x + 1
 
 =================================== MINIFIED ===================================
-let x=1,y=x+1
+let x = 1, y = x + 1;
+
 
 ==================================== SOURCE ====================================
 var x = 1; x + 1 === 2
 
 =================================== MINIFIED ===================================
-var x=1;x+1===2
+var x = 1;
+x + 1 === 2;
+
 
 ==================================== SOURCE ====================================
 var y = 1; 1 + y === 2
 
 =================================== MINIFIED ===================================
-var y=1;1+y===2
+var y = 1;
+1 + y === 2;
+
 
 ==================================== SOURCE ====================================
 null - Number(1)
 
 =================================== MINIFIED ===================================
-null-Number(1)
+null - Number(1);
+
 
 ==================================== SOURCE ====================================
 1 + 1.0000001
 
 =================================== MINIFIED ===================================
-2.0000001000000003
+2.0000001000000003;