From e2752f136f13888d8759a05b0ccadf65717073e7 Mon Sep 17 00:00:00 2001
From: Zheyu Zhang <zheyuzhang03@gmail.com>
Date: Fri, 14 Oct 2022 16:01:18 +0800
Subject: [PATCH 1/6] dont print > on new line

---
 src/res_printer.ml                            | 41 ++++++++++++++++++-
 .../reason/expected/bracedJsx.res.txt         |  3 +-
 tests/printer/expr/expected/jsx.res.txt       |  3 +-
 .../other/expected/signaturePicker.res.txt    |  6 +--
 4 files changed, 44 insertions(+), 9 deletions(-)

diff --git a/src/res_printer.ml b/src/res_printer.ml
index 60066d09..57af1aa8 100644
--- a/src/res_printer.ml
+++ b/src/res_printer.ml
@@ -3978,6 +3978,38 @@ and printPexpApply ~customLayout expr cmtTbl =
 
 and printJsxExpression ~customLayout lident args cmtTbl =
   let name = printJsxName lident in
+  let hasTailSingleLineComment =
+    let props =
+      args
+      |> List.filter (fun (label, _) ->
+             match label with
+             | Asttypes.Labelled "children" -> false
+             | Asttypes.Nolabel -> false
+             | _ -> true)
+    in
+    let getLast elements =
+      match List.rev elements with
+      | [] -> None
+      | last :: _ -> Some last
+    in
+    let tailComment =
+      match getLast props with
+      | None -> None
+      | Some (_, expr) -> (
+        let loc =
+          match expr.Parsetree.pexp_attributes with
+          | ({Location.txt = "ns.namedArgLoc"; loc}, _) :: _attrs ->
+            {loc with loc_end = expr.pexp_loc.loc_end}
+          | _ -> expr.pexp_loc
+        in
+        match Hashtbl.find_opt cmtTbl.CommentTable.trailing loc with
+        | None -> None
+        | Some comments -> getLast comments)
+    in
+    match tailComment with
+    | None -> false
+    | Some comment -> Comment.isSingleLineComment comment
+  in
   let formattedProps, children = printJsxProps ~customLayout args cmtTbl in
   (* <div className="test" /> *)
   let hasChildren =
@@ -4042,7 +4074,14 @@ and printJsxExpression ~customLayout lident args cmtTbl =
                     }
                   when isSelfClosing ->
                   Doc.concat [Doc.line; Doc.text "/>"]
-                | _ -> Doc.concat [Doc.softLine; Doc.greaterThan]);
+                | _ ->
+                  (* print_endline (string_of_bool hasTailSingleLineComment); *)
+                  Doc.concat
+                    [
+                      (if hasTailSingleLineComment then Doc.softLine
+                      else Doc.nil);
+                      Doc.greaterThan;
+                    ]);
               ]);
          (if isSelfClosing then Doc.nil
          else
diff --git a/tests/conversion/reason/expected/bracedJsx.res.txt b/tests/conversion/reason/expected/bracedJsx.res.txt
index 17d75e3d..b49e82fe 100644
--- a/tests/conversion/reason/expected/bracedJsx.res.txt
+++ b/tests/conversion/reason/expected/bracedJsx.res.txt
@@ -111,8 +111,7 @@ let make = () => {
     <div
       className=Styles.terminal
       onClick={event => (event->ReactEvent.Mouse.target)["querySelector"]("input")["focus"]()}
-      ref={containerRef->ReactDOMRe.Ref.domRef}
-    >
+      ref={containerRef->ReactDOMRe.Ref.domRef}>
       {state.history
       ->Array.mapWithIndex((index, item) =>
         <div key={j`$index`} className=Styles.line>
diff --git a/tests/printer/expr/expected/jsx.res.txt b/tests/printer/expr/expected/jsx.res.txt
index 326cbe3c..bdc104ff 100644
--- a/tests/printer/expr/expected/jsx.res.txt
+++ b/tests/printer/expr/expected/jsx.res.txt
@@ -104,8 +104,7 @@ let avatarSection =
           onMouseLeave={_ => setHoveringAdmin(false)}
           onClick={_e => {
             stopImpersonating(csrfToken)
-          }}
-        >
+          }}>
           <Avatar user={viewer} size={45} />
         </div>
       : React.nullElement}
diff --git a/tests/printer/other/expected/signaturePicker.res.txt b/tests/printer/other/expected/signaturePicker.res.txt
index fe32b18e..f73d98b8 100644
--- a/tests/printer/other/expected/signaturePicker.res.txt
+++ b/tests/printer/other/expected/signaturePicker.res.txt
@@ -28,8 +28,7 @@ let make = () => {
     <div className="pr-2 font-bold text-gray-400 text-lg"> {"Signature"->string} </div>
     <select
       id="country"
-      className="transition duration-150 ease-in-out sm:text-sm sm:leading-5 border-none font-bold text-2xl text-gray-600 bg-transparent"
-    >
+      className="transition duration-150 ease-in-out sm:text-sm sm:leading-5 border-none font-bold text-2xl text-gray-600 bg-transparent">
       {options
       ->Belt.List.map(option =>
         <option key={option->TimeSignature.toString}>
@@ -48,8 +47,7 @@ let make = () => {
       fill="none"
       strokeLinecap="round"
       strokeLinejoin="round"
-      className="text-gray-400"
-    >
+      className="text-gray-400">
       <polyline points="6 9 12 15 18 9" />
     </svg>
   </label>

From 53eae2125b7edd5542943caae24b2f4d86998e94 Mon Sep 17 00:00:00 2001
From: Zheyu Zhang <zheyuzhang03@gmail.com>
Date: Fri, 14 Oct 2022 16:49:47 +0800
Subject: [PATCH 2/6] clean and comment

---
 src/res_printer.ml | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/res_printer.ml b/src/res_printer.ml
index 57af1aa8..c95bcad4 100644
--- a/src/res_printer.ml
+++ b/src/res_printer.ml
@@ -3987,13 +3987,14 @@ and printJsxExpression ~customLayout lident args cmtTbl =
              | Asttypes.Nolabel -> false
              | _ -> true)
     in
-    let getLast elements =
-      match List.rev elements with
+    let rec getLastElement elements =
+      match elements with
       | [] -> None
-      | last :: _ -> Some last
+      | [element] -> Some element
+      | _ :: rest -> getLastElement rest
     in
     let tailComment =
-      match getLast props with
+      match getLastElement props with
       | None -> None
       | Some (_, expr) -> (
         let loc =
@@ -4004,7 +4005,7 @@ and printJsxExpression ~customLayout lident args cmtTbl =
         in
         match Hashtbl.find_opt cmtTbl.CommentTable.trailing loc with
         | None -> None
-        | Some comments -> getLast comments)
+        | Some comments -> getLastElement comments)
     in
     match tailComment with
     | None -> false
@@ -4075,9 +4076,9 @@ and printJsxExpression ~customLayout lident args cmtTbl =
                   when isSelfClosing ->
                   Doc.concat [Doc.line; Doc.text "/>"]
                 | _ ->
-                  (* print_endline (string_of_bool hasTailSingleLineComment); *)
                   Doc.concat
                     [
+                      (* print > on new line if last comment is single line comment *)
                       (if hasTailSingleLineComment then Doc.softLine
                       else Doc.nil);
                       Doc.greaterThan;

From 2094a63471915bab9994c641fe88fb0f9c903c5f Mon Sep 17 00:00:00 2001
From: Zheyu Zhang <zheyuzhang03@gmail.com>
Date: Sat, 15 Oct 2022 14:30:21 +0800
Subject: [PATCH 3/6] avoid walk props twice

---
 src/res_printer.ml | 122 +++++++++++++++++++++++++++------------------
 1 file changed, 74 insertions(+), 48 deletions(-)

diff --git a/src/res_printer.ml b/src/res_printer.ml
index c95bcad4..8ba221a1 100644
--- a/src/res_printer.ml
+++ b/src/res_printer.ml
@@ -3978,39 +3978,6 @@ and printPexpApply ~customLayout expr cmtTbl =
 
 and printJsxExpression ~customLayout lident args cmtTbl =
   let name = printJsxName lident in
-  let hasTailSingleLineComment =
-    let props =
-      args
-      |> List.filter (fun (label, _) ->
-             match label with
-             | Asttypes.Labelled "children" -> false
-             | Asttypes.Nolabel -> false
-             | _ -> true)
-    in
-    let rec getLastElement elements =
-      match elements with
-      | [] -> None
-      | [element] -> Some element
-      | _ :: rest -> getLastElement rest
-    in
-    let tailComment =
-      match getLastElement props with
-      | None -> None
-      | Some (_, expr) -> (
-        let loc =
-          match expr.Parsetree.pexp_attributes with
-          | ({Location.txt = "ns.namedArgLoc"; loc}, _) :: _attrs ->
-            {loc with loc_end = expr.pexp_loc.loc_end}
-          | _ -> expr.pexp_loc
-        in
-        match Hashtbl.find_opt cmtTbl.CommentTable.trailing loc with
-        | None -> None
-        | Some comments -> getLastElement comments)
-    in
-    match tailComment with
-    | None -> false
-    | Some comment -> Comment.isSingleLineComment comment
-  in
   let formattedProps, children = printJsxProps ~customLayout args cmtTbl in
   (* <div className="test" /> *)
   let hasChildren =
@@ -4074,15 +4041,8 @@ and printJsxExpression ~customLayout lident args cmtTbl =
                         Pexp_construct ({txt = Longident.Lident "[]"}, None);
                     }
                   when isSelfClosing ->
-                  Doc.concat [Doc.line; Doc.text "/>"]
-                | _ ->
-                  Doc.concat
-                    [
-                      (* print > on new line if last comment is single line comment *)
-                      (if hasTailSingleLineComment then Doc.softLine
-                      else Doc.nil);
-                      Doc.greaterThan;
-                    ]);
+                  Doc.text "/>"
+                | _ -> Doc.greaterThan);
               ]);
          (if isSelfClosing then Doc.nil
          else
@@ -4180,6 +4140,27 @@ and printJsxChildren ~customLayout (childrenExpr : Parsetree.expression) ~sep
 
 and printJsxProps ~customLayout args cmtTbl :
     Doc.t * Parsetree.expression option =
+  (* This function was introduced because we have different formatting behavior for self-closing tags and other tags
+     we always put /> on a new line for self-closing tag when it breaks
+     <A
+      a=""
+     />
+
+     <A
+     a="">
+      <B />
+     </A>
+     we should remove this function once the format is unified
+  *)
+  let isSelfClosing children =
+    match children with
+    | {
+     Parsetree.pexp_desc = Pexp_construct ({txt = Longident.Lident "[]"}, None);
+     pexp_loc = loc;
+    } ->
+      not (hasCommentsInside cmtTbl loc)
+    | _ -> false
+  in
   let rec loop props args =
     match args with
     | [] -> (Doc.nil, None)
@@ -4191,13 +4172,58 @@ and printJsxProps ~customLayout args cmtTbl :
            Pexp_construct ({txt = Longident.Lident "()"}, None);
        } );
     ] ->
+      (* we always put /> on a new line when a self-closing tag breaks *)
+      let doc = if isSelfClosing children then Doc.line else Doc.nil in
+      (doc, Some children)
+    | ((_, expr) as lastProp)
+      :: [
+           (Asttypes.Labelled "children", children);
+           ( Asttypes.Nolabel,
+             {
+               Parsetree.pexp_desc =
+                 Pexp_construct ({txt = Longident.Lident "()"}, None);
+             } );
+         ] ->
+      let hasTailSingleLineComment =
+        let rec getLastElement elements =
+          match elements with
+          | [] -> None
+          | [element] -> Some element
+          | _ :: rest -> getLastElement rest
+        in
+        let tailComment =
+          let loc =
+            match expr.Parsetree.pexp_attributes with
+            | ({Location.txt = "ns.namedArgLoc"; loc}, _) :: _attrs ->
+              {loc with loc_end = expr.pexp_loc.loc_end}
+            | _ -> expr.pexp_loc
+          in
+          match Hashtbl.find_opt cmtTbl.CommentTable.trailing loc with
+          | None -> None
+          | Some comments -> getLastElement comments
+        in
+        match tailComment with
+        | None -> false
+        | Some comment -> Comment.isSingleLineComment comment
+      in
+      let propDoc = printJsxProp ~customLayout lastProp cmtTbl in
       let formattedProps =
-        Doc.indent
-          (match props with
-          | [] -> Doc.nil
-          | props ->
-            Doc.concat
-              [Doc.line; Doc.group (Doc.join ~sep:Doc.line (props |> List.rev))])
+        Doc.concat
+          [
+            Doc.indent
+              (Doc.concat
+                 [
+                   Doc.line;
+                   Doc.group
+                     (Doc.join ~sep:Doc.line (propDoc :: props |> List.rev));
+                 ]);
+            (* print > on new line if last comment is single line comment *)
+            (match (isSelfClosing children, hasTailSingleLineComment) with
+            (* we always put /> on a new line when a self-closing tag breaks *)
+            | true, _ -> Doc.line
+            | false, true -> Doc.softLine
+            | false, false -> Doc.nil);
+          ]
       in
       (formattedProps, Some children)
     | arg :: args ->

From 1b849e18b4db8cad513ee3babc1d6aadd1d85d95 Mon Sep 17 00:00:00 2001
From: Zheyu Zhang <zheyuzhang03@gmail.com>
Date: Sat, 15 Oct 2022 22:01:10 +0800
Subject: [PATCH 4/6] consider tail comments of tag if there are no props

---
 src/res_printer.ml | 59 +++++++++++++++++++++++++++-------------------
 1 file changed, 35 insertions(+), 24 deletions(-)

diff --git a/src/res_printer.ml b/src/res_printer.ml
index 8ba221a1..f581cec6 100644
--- a/src/res_printer.ml
+++ b/src/res_printer.ml
@@ -113,6 +113,21 @@ let hasNestedJsxOrMoreThanOneChild expr =
   in
   loop false expr
 
+let hasTailSingleLineComment tbl loc =
+  let rec getLastElement elements =
+    match elements with
+    | [] -> None
+    | [element] -> Some element
+    | _ :: rest -> getLastElement rest
+  in
+  match Hashtbl.find_opt tbl.CommentTable.trailing loc with
+  | None -> false
+  | Some comments -> (
+    let lastComment = getLastElement comments in
+    match lastComment with
+    | None -> false
+    | Some comment -> Comment.isSingleLineComment comment)
+
 let hasCommentsInside tbl loc =
   match Hashtbl.find_opt tbl.CommentTable.inside loc with
   | None -> false
@@ -4042,7 +4057,19 @@ and printJsxExpression ~customLayout lident args cmtTbl =
                     }
                   when isSelfClosing ->
                   Doc.text "/>"
-                | _ -> Doc.greaterThan);
+                | _ ->
+                  (* if last trailing comment of tag is single line comment then put > on the next line
+                     <A
+                     // single line comment
+                     >
+                     </A>
+                  *)
+                  if hasTailSingleLineComment cmtTbl lident.Asttypes.loc then
+                    Doc.concat [Doc.softLine; Doc.greaterThan]
+                  else
+                    Doc.ifBreaks
+                      (Doc.lineSuffix Doc.greaterThan)
+                      Doc.greaterThan);
               ]);
          (if isSelfClosing then Doc.nil
          else
@@ -4172,7 +4199,6 @@ and printJsxProps ~customLayout args cmtTbl :
            Pexp_construct ({txt = Longident.Lident "()"}, None);
        } );
     ] ->
-      (* we always put /> on a new line when a self-closing tag breaks *)
       let doc = if isSelfClosing children then Doc.line else Doc.nil in
       (doc, Some children)
     | ((_, expr) as lastProp)
@@ -4184,28 +4210,13 @@ and printJsxProps ~customLayout args cmtTbl :
                  Pexp_construct ({txt = Longident.Lident "()"}, None);
              } );
          ] ->
-      let hasTailSingleLineComment =
-        let rec getLastElement elements =
-          match elements with
-          | [] -> None
-          | [element] -> Some element
-          | _ :: rest -> getLastElement rest
-        in
-        let tailComment =
-          let loc =
-            match expr.Parsetree.pexp_attributes with
-            | ({Location.txt = "ns.namedArgLoc"; loc}, _) :: _attrs ->
-              {loc with loc_end = expr.pexp_loc.loc_end}
-            | _ -> expr.pexp_loc
-          in
-          match Hashtbl.find_opt cmtTbl.CommentTable.trailing loc with
-          | None -> None
-          | Some comments -> getLastElement comments
-        in
-        match tailComment with
-        | None -> false
-        | Some comment -> Comment.isSingleLineComment comment
+      let loc =
+        match expr.Parsetree.pexp_attributes with
+        | ({Location.txt = "ns.namedArgLoc"; loc}, _) :: _attrs ->
+          {loc with loc_end = expr.pexp_loc.loc_end}
+        | _ -> expr.pexp_loc
       in
+      let tailSingleLineCommentPresent = hasTailSingleLineComment cmtTbl loc in
       let propDoc = printJsxProp ~customLayout lastProp cmtTbl in
       let formattedProps =
         Doc.concat
@@ -4218,7 +4229,7 @@ and printJsxProps ~customLayout args cmtTbl :
                      (Doc.join ~sep:Doc.line (propDoc :: props |> List.rev));
                  ]);
             (* print > on new line if last comment is single line comment *)
-            (match (isSelfClosing children, hasTailSingleLineComment) with
+            (match (isSelfClosing children, tailSingleLineCommentPresent) with
             (* we always put /> on a new line when a self-closing tag breaks *)
             | true, _ -> Doc.line
             | false, true -> Doc.softLine

From 0dbb05048769c5af7b2c123e6499d15b09b07553 Mon Sep 17 00:00:00 2001
From: Zheyu Zhang <zheyuzhang03@gmail.com>
Date: Sat, 15 Oct 2022 22:09:05 +0800
Subject: [PATCH 5/6] add more test case

---
 tests/printer/comments/expected/jsx.res.txt | 17 +++++++++++++++++
 tests/printer/comments/jsx.res              | 19 +++++++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/tests/printer/comments/expected/jsx.res.txt b/tests/printer/comments/expected/jsx.res.txt
index 6bd7d439..8c127c05 100644
--- a/tests/printer/comments/expected/jsx.res.txt
+++ b/tests/printer/comments/expected/jsx.res.txt
@@ -31,6 +31,23 @@ module Cite = {
   <B /* comment3 */ />
 </A>
 
+<A
+  value=""
+  /* comment */>
+  <B />
+</A>
+
+<A
+// comment
+>
+  <B />
+</A>
+
+<A
+/* comment */>
+  <B />
+</A>
+
 <div>
   // Must not jump inside braces
   {React.string("Hello, World!")}
diff --git a/tests/printer/comments/jsx.res b/tests/printer/comments/jsx.res
index c7f70082..3e38e180 100644
--- a/tests/printer/comments/jsx.res
+++ b/tests/printer/comments/jsx.res
@@ -33,6 +33,25 @@ value=""
   <B /* comment3 */ />
 </A>
 
+<A
+  value=""
+  /* comment */
+>
+  <B/>
+</A>
+
+<A
+// comment
+>
+  <B />
+</A>
+
+<A
+/* comment */
+>
+  <B />
+</A>
+
 <div>
   // Must not jump inside braces
   {React.string("Hello, World!")}

From cb2f04c4cf8bd61c85c37155d8565e49cd819049 Mon Sep 17 00:00:00 2001
From: Zheyu Zhang <zheyuzhang03@gmail.com>
Date: Sat, 15 Oct 2022 22:27:15 +0800
Subject: [PATCH 6/6] add more test case

---
 tests/printer/comments/expected/jsx.res.txt | 4 ++++
 tests/printer/comments/jsx.res              | 4 ++++
 2 files changed, 8 insertions(+)

diff --git a/tests/printer/comments/expected/jsx.res.txt b/tests/printer/comments/expected/jsx.res.txt
index 8c127c05..8fbf20d4 100644
--- a/tests/printer/comments/expected/jsx.res.txt
+++ b/tests/printer/comments/expected/jsx.res.txt
@@ -48,6 +48,10 @@ module Cite = {
   <B />
 </A>
 
+<A /* comment */>
+  <B />
+</A>
+
 <div>
   // Must not jump inside braces
   {React.string("Hello, World!")}
diff --git a/tests/printer/comments/jsx.res b/tests/printer/comments/jsx.res
index 3e38e180..d554e249 100644
--- a/tests/printer/comments/jsx.res
+++ b/tests/printer/comments/jsx.res
@@ -52,6 +52,10 @@ value=""
   <B />
 </A>
 
+<A /* comment */>
+  <B />
+</A>
+
 <div>
   // Must not jump inside braces
   {React.string("Hello, World!")}