Fix inline comment before spread syntax in record (#6615)

* WIP

* Refactor

* Add tests/Fix one broken spread test

* Handle case where spread coming from different module

* Fix expected output

* Only special case on priting ident

* Update changelog

Author: shulhi

CHANGELOG.md

@@ -28,6 +28,7 @@
 - Generic JSX transform: Handle namespaced names. https://github.com/rescript-lang/rescript-compiler/pull/6606
 - Fix issue with doc comment in recursive module. https://github.com/rescript-lang/rescript-compiler/pull/6613
 - Fix issue with Exceptions and Extensible types runtime generation. https://github.com/rescript-lang/rescript-compiler/pull/6570
+- Fix inline comment before spread syntax in record. https://github.com/rescript-lang/rescript-compiler/pull/6615
 
 #### :house: Internal
 

jscomp/syntax/src/res_printer.ml

@@ -2964,15 +2964,25 @@ and printExpression ~state (e : Parsetree.expression) cmtTbl =
         let spread =
           match spreadExpr with
           | None -> Doc.nil
-          | Some expr ->
+          | Some ({pexp_desc} as expr) ->
+            let doc =
+              match pexp_desc with
+              | Pexp_ident {txt = expr} -> printLident expr
+              | _ -> printExpression ~state expr cmtTbl
+            in
+            let docWithSpread =
+              Doc.concat
+                [
+                  Doc.dotdotdot;
+                  (match Parens.expr expr with
+                  | Parens.Parenthesized -> addParens doc
+                  | Braced braces -> printBraces doc expr braces
+                  | Nothing -> doc);
+                ]
+            in
             Doc.concat
               [
-                Doc.dotdotdot;
-                (let doc = printExpressionWithComments ~state expr cmtTbl in
-                 match Parens.expr expr with
-                 | Parens.Parenthesized -> addParens doc
-                 | Braced braces -> printBraces doc expr braces
-                 | Nothing -> doc);
+                printComments docWithSpread cmtTbl expr.Parsetree.pexp_loc;
                 Doc.comma;
                 Doc.line;
               ]

jscomp/syntax/tests/printer/comments/expected/expr.res.txt

@@ -125,7 +125,7 @@ let user = /* before */ {
 } // after
 
 let spreadUser = {
-  .../* before */ user1 /* after */,
+  /* before */ ...user1 /* after */,
   /* c0 */ age /* c1 */: /* c2 */ 32 /* c3 */,
 }
 
@@ -284,3 +284,43 @@ Doc.concat(list{
   rows,
   /* a */
 })
+
+// More record spread test
+type b = {
+  // spread a
+  ...a,
+  // spread c
+  ...c,
+  // no spread
+  b: string,
+}
+
+type a = {
+  // spread from different module
+  ...M.a,
+  // spread c
+  ...c,
+  // no spread
+  b: string,
+}
+
+let b = {
+  // exotic
+  ...\"let",
+  // foo
+  bar: "foo",
+}
+
+let b = {
+  // quote
+  ..."let",
+  // foo
+  bar: "foo",
+}
+
+let c = {
+  // from different module
+  ...M.a,
+  // foo
+  bar: "foo",
+}

jscomp/syntax/tests/printer/comments/expr.res

@@ -275,3 +275,43 @@ Doc.concat(list{
   rows,
   /* a */
 });
+
+// More record spread test
+type b = {
+  // spread a
+  ...a,
+  // spread c
+  ...c,
+  // no spread
+  b: string
+}
+
+type a = {
+  // spread from different module
+  ...M.a,
+  // spread c
+  ...c,
+  // no spread
+  b: string
+}
+
+let b = {
+  // exotic
+  ...\"let",
+  // foo
+  bar: "foo"
+}
+
+let b = {
+  // quote
+  ..."let",
+  // foo
+  bar: "foo"
+}
+
+let c = {
+  // from different module
+  ...M.a,
+  // foo
+  bar: "foo"
+}