Syntax sugar ["literal_string"] for SHARPOPs ## and #=

anmonteiro · Oct 2, 2018 · e6b959e · e6b959e
1 parent b9823e5
commit e6b959e
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Showing 5 changed files with 82 additions and 46 deletions.
diff --git a/formatTest/unit_tests/expected_output/basicStructures.re b/formatTest/unit_tests/expected_output/basicStructures.re
@@ -832,4 +832,4 @@ it("should remove parens", a => {
 });
 
 /* https://github.com/facebook/reason/issues/1554 */
-(curNode^)##childNodes;
+curNode^["childNodes"];
diff --git a/formatTest/unit_tests/expected_output/bucklescript.re b/formatTest/unit_tests/expected_output/bucklescript.re
@@ -20,20 +20,20 @@ x##y##z #= xxxx##yyyy##zzzz;
 let result =
   js_method_run1((!react)#createElement, foo);
 
-add(zz##yy, xx##ww);
+add(zz["yy"], xx["ww"]);
 
 /* These should print the same */
-let res = x##y + z##q; /* AST */
-let res = x##y + z##q; /* Minimum parens */
+let res = x["y"] + z["q"]; /* AST */
+let res = x["y"] + z["q"]; /* Minimum parens */
 
 /* These should print the same */
-let res = y + z##q##a; /* AST */
-let res = y + z##q##a; /* Min parens */
+let res = y + z["q"]["a"]; /* AST */
+let res = y + z["q"]["a"]; /* Min parens */
 
 /* Make sure it's actually parsed as left precedence
  * and that is maintained when printed */
-let res = z##(q##a); /* AST */
-let res = z##(q##a); /* Min parens */
+let res = z##(q["a"]); /* AST */
+let res = z##(q["a"]); /* Min parens */
 
 /* These should print the same */
 let res = !x##y; /* AST */
@@ -44,12 +44,12 @@ let res = !z##q##a; /* AST */
 let res = !z##q##a; /* Min parens */
 
 /* These should print the same */
-let res = ?!!x##y; /* AST */
-let res = ?!!x##y; /* Minimum parens */
+let res = ?!!x["y"]; /* AST */
+let res = ?!!x["y"]; /* Minimum parens */
 
 /* These should print the same */
-let res = ?!!z##(q##a); /* AST */
-let res = ?!!z##(q##a); /* Min parens */
+let res = ?!!z##(q["a"]); /* AST */
+let res = ?!!z##(q["a"]); /* Min parens */
 
 res #= ?!!z##q;
 res #= ?!!z##(q##a);

diff --git a/formatTest/unit_tests/expected_output/jsx.re b/formatTest/unit_tests/expected_output/jsx.re
@@ -124,13 +124,13 @@ let icon =
 
 <MessengerSharedPhotosAlbumViewPhotoReact
   ref=?{
-    foo##bar === baz ?
+    foo["bar"] === baz ?
       Some(
         foooooooooooooooooooooooo(setRefChild),
       ) :
       None
   }
-  key=node##legacy_attachment_id
+  key=node["legacy_attachment_id"]
 />;
 
 /* punning */
@@ -253,21 +253,21 @@ let (/></) = (a, b) => a + b;
 let x = foo /></ bar;
 
 /* https://github.com/facebook/reason/issues/870 */
-<div onClick=this##handleClick>
+<div onClick=this["handleClick"]>
   <> foo </>
 </div>;
 
-<div onClick=this##handleClick>
+<div onClick=this["handleClick"]>
   <> {foo(bar)} </>
 </div>;
 
 /* function application */
-<div onClick=this##handleClick>
+<div onClick=this["handleClick"]>
   <> {foo(bar)} </>
 </div>;
 
 /* tuple, not function application */
-<div onClick=this##handleClick>
+<div onClick=this["handleClick"]>
   <> foo bar </>
 </div>;
 

diff --git a/src/reason-parser/reason_parser.mly b/src/reason-parser/reason_parser.mly
@@ -2885,10 +2885,20 @@ mark_position_exp
   | simple_expr DOT as_loc(label_longident) EQUAL expr
     { mkexp(Pexp_setfield($1, $3, $5)) }
   | simple_expr LBRACKET expr RBRACKET EQUAL expr
-    { let loc = mklocation $symbolstartpos $endpos in
-      let exp = Pexp_ident(array_function ~loc "Array" "set") in
-      mkexp(Pexp_apply(mkexp ~ghost:true ~loc exp,
-                       [Nolabel,$1; Nolabel,$3; Nolabel,$6]))
+    { let {pexp_attributes;  pexp_desc } = $3 in
+      match pexp_desc with
+      | Pexp_constant(Pconst_string (label,_)) ->
+        let loc = mklocation $startpos($3) $endpos($3) in
+        let label_exp = mkexp ~attrs:pexp_attributes (Pexp_ident (mkloc (Lident label) loc)) ~loc in
+        mkinfixop
+          (mkinfixop $1 (mkoperator (ghloc "##")) label_exp)
+          (mkoperator (ghloc "#="))
+          $6
+      | _ ->
+        let loc = mklocation $symbolstartpos $endpos in
+        let exp = Pexp_ident(array_function ~loc "Array" "set") in
+        mkexp(Pexp_apply(mkexp ~ghost:true ~loc exp,
+                         [Nolabel,$1; Nolabel,$3; Nolabel,$6]))
     }
   | simple_expr DOT LBRACKET expr RBRACKET EQUAL expr
     { let loc = mklocation $symbolstartpos $endpos in
@@ -3026,9 +3036,16 @@ parenthesized_expr:
                        mkexp(Pexp_object(Cstr.mk pat []))))
     }
   | E LBRACKET expr RBRACKET
-    { let loc = mklocation $symbolstartpos $endpos in
-      let exp = Pexp_ident(array_function ~loc "Array" "get") in
-      mkexp(Pexp_apply(mkexp ~ghost:true ~loc exp, [Nolabel,$1; Nolabel,$3]))
+    { let {pexp_attributes;  pexp_desc } = $3 in
+      match pexp_desc with
+      | Pexp_constant(Pconst_string (label,_)) ->
+        let loc = mklocation $startpos($3) $endpos($3) in
+        let label_exp = mkexp ~attrs:pexp_attributes (Pexp_ident (mkloc (Lident label) loc)) ~loc in
+        mkinfixop $1 (mkoperator (ghloc "##")) label_exp
+      | _ ->
+        let loc = mklocation $symbolstartpos $endpos in
+        let exp = Pexp_ident(array_function ~loc "Array" "get") in
+        mkexp(Pexp_apply(mkexp ~ghost:true ~loc exp, [Nolabel,$1; Nolabel,$3]))
     }
   | E as_loc(LBRACKET) expr as_loc(error)
     { unclosed_exp (with_txt $2 "(") (with_txt $4 ")") }

diff --git a/src/reason-parser/reason_pprint_ast.ml b/src/reason-parser/reason_pprint_ast.ml
@@ -2048,6 +2048,16 @@ let isSingleArgParenApplication = function
   | [({pexp_attributes = []} as exp)] when (is_simple_list_expr exp) -> true
   | _ -> false
 
+let rec isChainOfSharpOpApplications = function
+  | {pexp_desc = (Pexp_apply (eFun, [(_,e1); (_, e2)]))}
+    when printedStringAndFixityExpr eFun = Infix "##" -> (
+    match e1, e2 with
+      | {pexp_desc = Pexp_ident {txt = Lident _}}, {pexp_desc = Pexp_ident {txt = Lident _}} -> true
+      | _, {pexp_desc = Pexp_ident {txt = Lident _}} -> isChainOfSharpOpApplications e1
+      | _ -> false
+  )
+  | _ -> false
+
 (*
  * Determines if the arguments of a constructor pattern match need
  * special printing. If there's one argument & they have some kind of wrapping,
@@ -3392,6 +3402,8 @@ let printer = object(self:'self)
     if e.pexp_attributes != [] then None
     (* should also check attributes underneath *)
     else match e.pexp_desc with
+      | Pexp_apply ({pexp_desc=Pexp_ident{txt=Lident "#="}}, [(_,e1);(_,e2)]) ->
+        Some (self#simple_enough_to_be_lhs_dot_send e1, e2)
       | Pexp_apply ({pexp_desc=Pexp_ident{txt=Ldot (Lident ("Array"), "set")}}, [(_,e1);(_,e2);(_,e3)]) ->
         let prec = Custom "prec_lbracket" in
         let lhs = self#unparseResolvedRule (
@@ -4003,27 +4015,34 @@ let printer = object(self:'self)
           )
           in
           Simple (label ~space:forceSpace leftItm (atom postfixStr))
-        | (Infix printedIdent, [(Nolabel, leftExpr); (Nolabel, rightExpr)]) ->
-          let infixToken = Token printedIdent in
-          let rightItm = self#ensureContainingRule ~withPrecedence:infixToken ~reducesAfterRight:rightExpr () in
-          let leftItm = self#ensureExpression ~reducesOnToken:infixToken leftExpr in
-          (* Left exprs of infix tokens which we don't print spaces for (e.g. `##`)
-             need to be wrapped in parens in the case of postfix `^`. Otherwise,
-             printing will be ambiguous as `^` is also a valid start of an infix
-             operator. *)
-          let formattedLeftItm = (match leftItm with
-            | LayoutNode x -> begin match leftExpr.pexp_desc with
-                | Pexp_apply (e,_) ->
-                  (match printedStringAndFixityExpr e with
-                   | UnaryPostfix "^" when requireNoSpaceFor printedIdent ->
-                     LayoutNode (formatPrecedence ~loc:leftExpr.pexp_loc x)
-                   | _ -> leftItm)
-                | _ -> leftItm
-              end
-            | InfixTree _ -> leftItm
-          ) in
-          let infixTree = InfixTree (printedIdent, formattedLeftItm, rightItm) in
-          SpecificInfixPrecedence ({reducePrecedence=infixToken; shiftPrecedence=infixToken}, infixTree)
+        | (Infix printedIdent, [(Nolabel, leftExpr); (Nolabel, rightExpr)]) -> (
+          match printedIdent, rightExpr with
+          | "##", {pexp_desc = Pexp_ident({txt = Lident _})} ->
+            Simple (self#access "[" "]"
+                    (self#simple_enough_to_be_lhs_dot_send leftExpr)
+                    (makeList ~wrap:("\"", "\"") [(self#unparseExpr rightExpr)]))
+          | _ ->
+            let infixToken = Token printedIdent in
+            let rightItm = self#ensureContainingRule ~withPrecedence:infixToken ~reducesAfterRight:rightExpr () in
+            let leftItm = self#ensureExpression ~reducesOnToken:infixToken leftExpr in
+            (* Left exprs of infix tokens which we don't print spaces for (e.g. `##`)
+               need to be wrapped in parens in the case of postfix `^`. Otherwise,
+               printing will be ambiguous as `^` is also a valid start of an infix
+               operator. *)
+            let formattedLeftItm = (match leftItm with
+              | LayoutNode x -> begin match leftExpr.pexp_desc with
+                  | Pexp_apply (e,_) ->
+                    (match printedStringAndFixityExpr e with
+                     | UnaryPostfix "^" when requireNoSpaceFor printedIdent ->
+                       LayoutNode (formatPrecedence ~loc:leftExpr.pexp_loc x)
+                     | _ -> leftItm)
+                  | _ -> leftItm
+                end
+              | InfixTree _ -> leftItm
+            ) in
+            let infixTree = InfixTree (printedIdent, formattedLeftItm, rightItm) in
+            SpecificInfixPrecedence ({reducePrecedence=infixToken; shiftPrecedence=infixToken}, infixTree)
+        )
         (* Will be rendered as `(+) a b c` which is parsed with higher precedence than all
            the other forms unparsed here.*)
         | (UnaryPlusPrefix printedIdent, [(Nolabel, rightExpr)]) ->