fix(codegen): preserve coverage comments before object properties (#21312)

Closes #21302

---------

Co-authored-by: Dunqing <dengqing0821@gmail.com>

apps/oxlint/src-js/generated/deserialize.js

@@ -21,6 +21,7 @@ for (let i = 0; i <= 64; i++) stringDecodeArrays[i] = Array(i).fill(0);
 
 const NodeProto = Object.create(Object.prototype, {
   loc: {
+    // Note: Not configurable
     get() {
       return getNodeLoc(this);
     },
@@ -4967,6 +4968,7 @@ function deserializeTSModuleDeclaration(pos) {
       __proto__: NodeProto,
       type: "TSModuleDeclaration",
       id: null,
+      // No `body` field
       kind,
       declare,
       global: false,

crates/oxc_codegen/src/gen.rs

@@ -1586,9 +1586,17 @@ impl GenExpr for ObjectExpression<'_> {
                 }
                 if is_multi_line {
                     p.print_soft_newline();
+                    p.print_comments_at(item.span().start);
                     p.print_indent();
                 } else {
                     p.print_soft_space();
+                    if let Some(comments) = p.get_comments(item.span().start) {
+                        p.print_comments(&comments);
+                        if p.print_next_indent_as_space {
+                            p.print_hard_space();
+                            p.print_next_indent_as_space = false;
+                        }
+                    }
                 }
                 item.print(p, ctx);
             }

crates/oxc_codegen/tests/integration/comments.rs

@@ -229,6 +229,27 @@ catch (err) // v8 ignore next
   case 0.5: break;
   /* istanbul ignore next */
   default: break;
+}",
+            // Coverage comment before ObjectExpression property
+            // https://github.com/oxc-project/oxc/issues/21302
+            "const obj = {
+  a: () => 1,
+  /* v8 ignore next */
+  b: () => 2,
+}",
+            // Coverage comment before single ObjectExpression property
+            "const obj = { /* v8 ignore next */ a: () => 1 }",
+            // Coverage comment before the first ObjectExpression property
+            "const obj = {
+  /* v8 ignore next */
+  a: () => 1,
+  b: () => 2,
+}",
+            // Coverage comment before a SpreadElement in ObjectExpression
+            "const obj = {
+  a: 1,
+  /* v8 ignore next */
+  ...rest,
 }",
         ];
 

crates/oxc_codegen/tests/integration/snapshots/coverage.snap

@@ -158,3 +158,47 @@ switch (Math.random()) {
 	/* istanbul ignore next */
 	default: break;
 }
+
+########## 25
+const obj = {
+  a: () => 1,
+  /* v8 ignore next */
+  b: () => 2,
+}
+----------
+const obj = {
+	a: () => 1,
+	/* v8 ignore next */
+	b: () => 2
+};
+
+########## 26
+const obj = { /* v8 ignore next */ a: () => 1 }
+----------
+const obj = { /* v8 ignore next */ a: () => 1 };
+
+########## 27
+const obj = {
+  /* v8 ignore next */
+  a: () => 1,
+  b: () => 2,
+}
+----------
+const obj = {
+	/* v8 ignore next */
+	a: () => 1,
+	b: () => 2
+};
+
+########## 28
+const obj = {
+  a: 1,
+  /* v8 ignore next */
+  ...rest,
+}
+----------
+const obj = {
+	a: 1,
+	/* v8 ignore next */
+	...rest
+};

napi/parser/src-js/generated/deserialize/js.js

@@ -3630,6 +3630,7 @@ function deserializeTSModuleDeclaration(pos) {
     node = {
       type: "TSModuleDeclaration",
       id: null,
+      // No `body` field
       kind,
       declare,
       global: false,

napi/parser/src-js/generated/deserialize/js_parent.js

@@ -4056,6 +4056,7 @@ function deserializeTSModuleDeclaration(pos) {
     node = parent = {
       type: "TSModuleDeclaration",
       id: null,
+      // No `body` field
       kind,
       declare,
       global: false,

napi/parser/src-js/generated/deserialize/js_range.js

@@ -4065,6 +4065,7 @@ function deserializeTSModuleDeclaration(pos) {
     node = {
       type: "TSModuleDeclaration",
       id: null,
+      // No `body` field
       kind,
       declare,
       global: false,

napi/parser/src-js/generated/deserialize/js_range_parent.js

@@ -4489,6 +4489,7 @@ function deserializeTSModuleDeclaration(pos) {
     node = parent = {
       type: "TSModuleDeclaration",
       id: null,
+      // No `body` field
       kind,
       declare,
       global: false,

napi/parser/src-js/generated/deserialize/ts.js

@@ -3903,6 +3903,7 @@ function deserializeTSModuleDeclaration(pos) {
     node = {
       type: "TSModuleDeclaration",
       id: null,
+      // No `body` field
       kind,
       declare,
       global: false,

napi/parser/src-js/generated/deserialize/ts_parent.js

@@ -4359,6 +4359,7 @@ function deserializeTSModuleDeclaration(pos) {
     node = parent = {
       type: "TSModuleDeclaration",
       id: null,
+      // No `body` field
       kind,
       declare,
       global: false,

napi/parser/src-js/generated/deserialize/ts_range.js

@@ -4366,6 +4366,7 @@ function deserializeTSModuleDeclaration(pos) {
     node = {
       type: "TSModuleDeclaration",
       id: null,
+      // No `body` field
       kind,
       declare,
       global: false,

napi/parser/src-js/generated/deserialize/ts_range_parent.js

@@ -4820,6 +4820,7 @@ function deserializeTSModuleDeclaration(pos) {
     node = parent = {
       type: "TSModuleDeclaration",
       id: null,
+      // No `body` field
       kind,
       declare,
       global: false,