Fix printing of await expression inside binary expressions

Author: Maxim

src/res_parsetree_viewer.ml

@@ -523,17 +523,15 @@ let isPrintableAttribute attr =
   match attr with
   | ( {
         Location.txt =
-          ( "bs" | "res.template" | "ns.ternary" | "ns.braces" | "ns.iflet"
-          | "JSX" );
+          ( "bs" | "ns.iflet" | "ns.braces" | "JSX" | "res.async" | "res.await"
+          | "res.template" | "ns.ternary" );
       },
       _ ) ->
     false
   | _ -> true
 
 let hasPrintableAttributes attrs = List.exists isPrintableAttribute attrs
 
-let filterPrintableAttributes attrs = List.filter isPrintableAttribute attrs
-
 let partitionPrintableAttributes attrs =
   List.partition isPrintableAttribute attrs
 

src/res_parsetree_viewer.mli

@@ -99,7 +99,6 @@ val hasOptionalAttribute : Parsetree.attributes -> bool
 val shouldIndentBinaryExpr : Parsetree.expression -> bool
 val shouldInlineRhsBinaryExpr : Parsetree.expression -> bool
 val hasPrintableAttributes : Parsetree.attributes -> bool
-val filterPrintableAttributes : Parsetree.attributes -> Parsetree.attributes
 val partitionPrintableAttributes :
   Parsetree.attributes -> Parsetree.attributes * Parsetree.attributes
 

src/res_printer.ml

@@ -3519,28 +3519,28 @@ and printBinaryExpression ~customLayout (expr : Parsetree.expression) cmtTbl =
           then
             let leftPrinted = flatten ~isLhs:true left operator in
             let rightPrinted =
-              let _, rightAttrs =
+              let rightPrinteableAttrs, rightInternalAttrs =
                 ParsetreeViewer.partitionPrintableAttributes
                   right.pexp_attributes
               in
               let doc =
                 printExpressionWithComments ~customLayout
-                  {right with pexp_attributes = rightAttrs}
+                  {right with pexp_attributes = rightInternalAttrs}
                   cmtTbl
               in
               let doc =
                 if Parens.flattenOperandRhs parentOperator right then
                   Doc.concat [Doc.lparen; doc; Doc.rparen]
                 else doc
               in
-              let printableAttrs =
-                ParsetreeViewer.filterPrintableAttributes right.pexp_attributes
-              in
               let doc =
                 Doc.concat
-                  [printAttributes ~customLayout printableAttrs cmtTbl; doc]
+                  [
+                    printAttributes ~customLayout rightPrinteableAttrs cmtTbl;
+                    doc;
+                  ]
               in
-              match printableAttrs with
+              match rightPrinteableAttrs with
               | [] -> doc
               | _ -> addParens doc
             in
@@ -3559,22 +3559,25 @@ and printBinaryExpression ~customLayout (expr : Parsetree.expression) cmtTbl =
             in
             printComments doc cmtTbl expr.pexp_loc
           else
+            let printeableAttrs, internalAttrs =
+              ParsetreeViewer.partitionPrintableAttributes expr.pexp_attributes
+            in
             let doc =
               printExpressionWithComments ~customLayout
-                {expr with pexp_attributes = []}
+                {expr with pexp_attributes = internalAttrs}
                 cmtTbl
             in
             let doc =
               if
                 Parens.subBinaryExprOperand parentOperator operator
-                || expr.pexp_attributes <> []
+                || printeableAttrs <> []
                    && (ParsetreeViewer.isBinaryExpression expr
                       || ParsetreeViewer.isTernaryExpr expr)
               then Doc.concat [Doc.lparen; doc; Doc.rparen]
               else doc
             in
             Doc.concat
-              [printAttributes ~customLayout expr.pexp_attributes cmtTbl; doc]
+              [printAttributes ~customLayout printeableAttrs cmtTbl; doc]
         | _ -> assert false
       else
         match expr.pexp_desc with

test.res

@@ -29,4 +29,9 @@ assert (await f())
 
 user.data = await fetch()
 
-<Navbar promise={await gc()}>{await weirdReactSuspenseApi}</Navbar>
+<Navbar promise={await gc()}>{await weirdReactSuspenseApi}</Navbar>
+
+let inBinaryExpression = await x->Js.Promise.resolve + 1
+let inBinaryExpression = await x->Js.Promise.resolve + await y->Js.Promise.resolve
+
+let () = await (await fetch(url))->(await resolve)

tests/printer/expr/asyncAwait.res

@@ -29,3 +29,8 @@ assert (await f())
 user.data = await fetch()
 
 <Navbar promise={await gc()}> {await weirdReactSuspenseApi} </Navbar>
+
+let inBinaryExpression = (await x)->Js.Promise.resolve + 1
+let inBinaryExpression = (await x)->Js.Promise.resolve + (await y)->Js.Promise.resolve
+
+let () = (await fetch(url))->(await resolve)