Implement printer support for numeric poly var

Author: Iwan

src/res_printer.ml

@@ -425,15 +425,42 @@ let printIdentLike ?allowUident txt =
     ]
   | NormalIdent -> Doc.text txt
 
+let rec unsafe_for_all_range s ~start ~finish p =
+  start > finish ||
+  p (String.unsafe_get s start) &&
+  unsafe_for_all_range s ~start:(start + 1) ~finish p
+
+let for_all_from s start  p =
+  let len = String.length s in
+  if start < 0  then invalid_arg "Ext_string.for_all_from"
+  else unsafe_for_all_range s ~start ~finish:(len - 1) p
+
+(* See https://github.com/rescript-lang/rescript-compiler/blob/726cfa534314b586e5b5734471bc2023ad99ebd9/jscomp/ext/ext_string.ml#L510 *)
+let isValidNumericPolyvarNumber (x : string) =
+  let len = String.length x in
+  len > 0 && (
+    let a = Char.code (String.unsafe_get x 0) in
+    a <= 57 &&
+    (if len > 1 then
+       a > 48 &&
+       for_all_from x 1 (function '0' .. '9' -> true | _ -> false)
+     else
+       a >= 48 )
+  )
+
 (* Exotic identifiers in poly-vars have a "lighter" syntax: #"ease-in" *)
 let printPolyVarIdent txt =
-  match classifyIdentContent ~allowUident:true txt with
-  | ExoticIdent -> Doc.concat [
-      Doc.text "\"";
-      Doc.text txt;
-      Doc.text"\""
-    ]
-  | NormalIdent -> Doc.text txt
+  (* numeric poly-vars don't need quotes: #644 *)
+  if isValidNumericPolyvarNumber txt then
+    Doc.text txt
+  else
+    match classifyIdentContent ~allowUident:true txt with
+    | ExoticIdent -> Doc.concat [
+        Doc.text "\"";
+        Doc.text txt;
+        Doc.text"\""
+      ]
+    | NormalIdent -> Doc.text txt
 
 
 let printLident l = match l with

tests/printer/expr/__snapshots__/render.spec.js.snap

@@ -3456,12 +3456,12 @@ let r = #lident(a, b)
 let r = #\\"exotic lident\\"
 let r = #\\"exotic lident\\"(a, b)
 
-let x = #\\"1\\"
-let x = #\\"123\\"
+let x = #1
+let x = #123
 let x = #\\"10space\\"
 let x = #space10
 
-let a = #\\"1\\"
+let a = #1
 let b = #\\"1a\\"
 let c = #a2
 let d = #abcd

tests/printer/expr/expected/polyvariant.res.txt

@@ -108,12 +108,12 @@ let r = #lident(a, b)
 let r = #"exotic lident"
 let r = #"exotic lident"(a, b)
 
-let x = #"1"
-let x = #"123"
+let x = #1
+let x = #123
 let x = #"10space"
 let x = #space10
 
-let a = #"1"
+let a = #1
 let b = #"1a"
 let c = #a2
 let d = #abcd

tests/printer/pattern/__snapshots__/render.spec.js.snap

@@ -429,8 +429,8 @@ let #Shape = x
 let #\\"type\\" = x
 let #\\"test 🏚\\" = x
 let #\\"Shape✅\\" = x
-let #\\"1\\" = x
-let #\\"123\\" = x
+let #1 = x
+let #123 = x
 let #\\"10space\\" = x
 
 let #space10 = x
@@ -453,8 +453,8 @@ let cmp = (selectedChoice, value) =>
   | (#...a: typ) => true
   | lazy #...a => true
   | exception #...a => true
-  | #\\"1\\" => true
-  | #\\"123\\" => true
+  | #1 => true
+  | #123 => true
   | #\\"10space\\" => x
   | #space10 => x
   | _ => false

tests/printer/pattern/expected/variant.res.txt

@@ -3,8 +3,8 @@ let #Shape = x
 let #"type" = x
 let #"test 🏚" = x
 let #"Shape✅" = x
-let #"1" = x
-let #"123" = x
+let #1 = x
+let #123 = x
 let #"10space" = x
 
 let #space10 = x
@@ -27,8 +27,8 @@ let cmp = (selectedChoice, value) =>
   | (#...a: typ) => true
   | lazy #...a => true
   | exception #...a => true
-  | #"1" => true
-  | #"123" => true
+  | #1 => true
+  | #123 => true
   | #"10space" => x
   | #space10 => x
   | _ => false

tests/printer/typexpr/__snapshots__/render.spec.js.snap

@@ -756,5 +756,10 @@ type currencyPoly = [
 
 type t = [s]
 type t = [ListStyleType.t]
+
+type permissions = [
+  | #777
+  | #644
+]
 "
 `;

tests/printer/typexpr/expected/variant.res.txt

@@ -102,3 +102,8 @@ type currencyPoly = [
 
 type t = [s]
 type t = [ListStyleType.t]
+
+type permissions = [
+  | #777
+  | #644
+]

tests/printer/typexpr/variant.res

@@ -96,3 +96,8 @@ type currencyPoly = [#UUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUSD | #CAAA
 
 type t = [s]
 type t = [ListStyleType.t];
+
+type permissions = [
+  | #777
+  | #644
+]