fix(codegen): print negative bigint 1n- -1n correctly after constant folding (#6798)

closes #6767

bacon.toml

@@ -1,5 +1,5 @@
 [jobs.example]
-command = ["just", "run-example"]
+command = ["just", "example"]
 allow_warnings = true
 need_stdout = true
 

crates/oxc_codegen/src/gen.rs

@@ -1147,6 +1147,10 @@ impl<'a> GenExpr for NumericLiteral<'a> {
 
 impl<'a> Gen for BigIntLiteral<'a> {
     fn gen(&self, p: &mut Codegen, _ctx: Context) {
+        if self.raw.starts_with('-') {
+            p.print_space_before_operator(Operator::Unary(UnaryOperator::UnaryNegation));
+        }
+        p.print_space_before_identifier();
         p.add_source_mapping(self.span.start);
         p.print_str(self.raw.as_str());
     }

crates/oxc_minifier/src/ast_passes/peephole_fold_constants.rs

@@ -601,6 +601,12 @@ mod test {
         tester::test(&allocator, source_text, expected, &mut pass);
     }
 
+    fn test_nospace(source_text: &str, expected: &str) {
+        let allocator = Allocator::default();
+        let mut pass = super::PeepholeFoldConstants::new();
+        tester::test_impl(&allocator, source_text, expected, &mut pass, true);
+    }
+
     fn test_same(source_text: &str) {
         test(source_text, source_text);
     }
@@ -1312,6 +1318,10 @@ mod test {
         test("x = 0 / 0", "x = NaN");
         test("x = 0 % 0", "x = NaN");
         test("x = (-1) ** 0.5", "x = NaN");
+
+        test_nospace("1n+ +1n", "1n + +1n");
+        test_nospace("1n- -1n", "1n - -1n");
+        test_nospace("a- -b", "a - -b");
     }
 
     #[test]

crates/oxc_minifier/src/tester.rs

@@ -13,8 +13,18 @@ pub fn test<'a, P: CompressorPass<'a>>(
     expected: &'a str,
     pass: &mut P,
 ) {
-    let result = run(allocator, source_text, Some(pass));
-    let expected = run::<P>(allocator, expected, None);
+    test_impl(allocator, source_text, expected, pass, false);
+}
+
+pub fn test_impl<'a, P: CompressorPass<'a>>(
+    allocator: &'a Allocator,
+    source_text: &'a str,
+    expected: &'a str,
+    pass: &mut P,
+    remove_whitespace: bool,
+) {
+    let result = run(allocator, source_text, Some(pass), remove_whitespace);
+    let expected = run::<P>(allocator, expected, None, remove_whitespace);
     assert_eq!(result, expected, "\nfor source\n{source_text}\nexpect\n{expected}\ngot\n{result}");
 }
 
@@ -22,6 +32,7 @@ fn run<'a, P: CompressorPass<'a>>(
     allocator: &'a Allocator,
     source_text: &'a str,
     pass: Option<&mut P>,
+    remove_whitespace: bool,
 ) -> String {
     let source_type = SourceType::mjs();
     let mut program = Parser::new(allocator, source_text, source_type).parse().program;
@@ -35,7 +46,11 @@ fn run<'a, P: CompressorPass<'a>>(
     }
 
     CodeGenerator::new()
-        .with_options(CodegenOptions { single_quote: true, ..CodegenOptions::default() })
+        .with_options(CodegenOptions {
+            single_quote: true,
+            minify: remove_whitespace,
+            ..CodegenOptions::default()
+        })
         .build(&program)
         .code
 }

justfile

@@ -49,7 +49,7 @@ watch:
 example tool *args='':
   cargo --color always run -p oxc_{{tool}} --example {{tool}} -- {{args}}
 
-watch-example args='':
+watch-example *args='':
   bacon example -- {{args}}
 
 # Generate AST related boilerplate code.

tasks/coverage/snapshots/runtime.snap

@@ -2,7 +2,7 @@ commit: 06454619
 
 runtime Summary:
 AST Parsed     : 18446/18446 (100.00%)
-Positive Passed: 17182/18446 (93.15%)
+Positive Passed: 17183/18446 (93.15%)
 tasks/coverage/test262/test/annexB/language/function-code/block-decl-func-block-scoping.js
 minify error: ReferenceError: f is not defined
 
@@ -2088,9 +2088,6 @@ minify error: Test262Error: Expected SameValue(«"a"», «"m"») to be true
 tasks/coverage/test262/test/language/expressions/subtraction/S11.6.2_A4_T5.js
 minify error: Test262Error: #3.2: -0 - 0 === - 0. Actual: +0
 
-tasks/coverage/test262/test/language/expressions/subtraction/bigint-arithmetic.js
-minify error: SyntaxError: Invalid left-hand side expression in postfix operation
-
 tasks/coverage/test262/test/language/expressions/super/call-spread-err-mult-err-obj-unresolvable.js
 transform error: ReferenceError: require is not defined