fix string escape problem across different OSes, in ocaml 4.02.3, the escape is locale sensitive

Author: Hongbo Zhang

jscomp/compiler.mllib

@@ -16,6 +16,7 @@ ext_pp
 ext_option
 ext_list
 ext_string
+ext_char
 ext_format
 ext_filename
 ext_marshal

jscomp/ext_char.ml

@@ -0,0 +1,50 @@
+(* OCamlScript compiler
+ * Copyright (C) 2015-2016 Bloomberg Finance L.P.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, with linking exception;
+ * either version 2.1 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *)
+
+(* Author: Hongbo Zhang  *)
+
+
+external string_unsafe_set : string -> int -> char -> unit
+                           = "%string_unsafe_set"
+
+external string_create: int -> string = "caml_create_string"
+
+external unsafe_chr: int -> char = "%identity"
+
+(** {!Char.escaped} is locale sensitive in 4.02.3, fixed in the trunk,
+    backport it here
+ *)
+let escaped = function
+  | '\'' -> "\\'"
+  | '\\' -> "\\\\"
+  | '\n' -> "\\n"
+  | '\t' -> "\\t"
+  | '\r' -> "\\r"
+  | '\b' -> "\\b"
+  | ' ' .. '~' as c ->
+      let s = string_create 1 in
+      string_unsafe_set s 0 c;
+      s
+  | c ->
+      let n = Char.code c in
+      let s = string_create 4 in
+      string_unsafe_set s 0 '\\';
+      string_unsafe_set s 1 (unsafe_chr (48 + n / 100));
+      string_unsafe_set s 2 (unsafe_chr (48 + (n / 10) mod 10));
+      string_unsafe_set s 3 (unsafe_chr (48 + n mod 10));
+      s

jscomp/ext_char.mli

@@ -0,0 +1,21 @@
+(* OCamlScript compiler
+ * Copyright (C) 2015-2016 Bloomberg Finance L.P.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, with linking exception;
+ * either version 2.1 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *)
+
+(* Author: Hongbo Zhang  *)
+
+val escaped : char -> string

jscomp/ext_string.ml

@@ -63,3 +63,21 @@ let ends_with s beg =
         aux (j - 1) (k - 1)
       else  false in 
     aux s_finish s_beg
+
+
+(**  In OCaml 4.02.3, {!String.escaped} is locale senstive, 
+     this version try to make it not locale senstive, this bug is fixed
+     in the compiler trunk     
+*)
+let escaped s =
+  let rec needs_escape i =
+    if i >= String.length s then false else
+      match String.unsafe_get s i with
+      | '"' | '\\' | '\n' | '\t' | '\r' | '\b' -> true
+      | ' ' .. '~' -> needs_escape (i+1)
+      | _ -> true
+  in
+  if needs_escape 0 then
+    Bytes.unsafe_to_string (Bytes.escaped (Bytes.unsafe_of_string s))
+  else
+    s

jscomp/ext_string.mli

@@ -31,3 +31,5 @@ val split : ?keep_empty:bool -> string -> char -> string list
 val starts_with : string -> string -> bool
 
 val ends_with : string -> string -> bool
+
+val escaped : string -> string

jscomp/j_helper.ml

@@ -300,7 +300,7 @@ module Exp = struct
     match v.expression_desc with 
     | Str (_, x) ->
         assert (String.length x = 1) ;
-        int ~comment:(Printf.sprintf "%S" x)  
+        int ~comment:("\"" ^ Ext_string.escaped  x ^ "\"")  
           (Char.code x.[0])
     | Char_of_int v -> v 
     | _ -> {comment; expression_desc = Char_to_int v }

jscomp/js_of_lam_string.ml

@@ -26,7 +26,6 @@ module E = J_helper.Exp
 module A = struct 
 
   let const_char (i : char) = 
-    (* E.int  ~comment:(Char.escaped i) (Char.code i) *)
     E.str (String.make 1 i)
 
   let caml_char_of_int ?comment (v : J.expression)  =  
@@ -82,7 +81,7 @@ end
 module B = struct 
 
   let const_char (i : char) = 
-    E.int  ~comment:(Printf.sprintf "%S" (String.make 1 i)) 
+    E.int  ~comment:("\"" ^ Ext_string.escaped (String.make 1 i) ^ "\"") 
       ~c:i (Char.code i)
 
   let caml_char_of_int ?comment (v : J.expression)  =  v

jscomp/test/.depend

@@ -64,8 +64,8 @@ ext_filename.cmx : ../stdlib/sys.cmx ../stdlib/string.cmx ../stdlib/list.cmx \
     ../stdlib/filename.cmx ext_string.cmx
 ext_list.cmo : ../stdlib/list.cmi ../stdlib/array.cmi
 ext_list.cmx : ../stdlib/list.cmx ../stdlib/array.cmx
-ext_string.cmo : ../stdlib/string.cmi
-ext_string.cmx : ../stdlib/string.cmx
+ext_string.cmo : ../stdlib/string.cmi ../stdlib/bytes.cmi
+ext_string.cmx : ../stdlib/string.cmx ../stdlib/bytes.cmx
 fib.cmo :
 fib.cmx :
 for_loop_test.cmo : mt.cmo ../stdlib/list.cmi ../stdlib/array.cmi
@@ -390,8 +390,8 @@ ext_filename.cmo : ../stdlib/sys.cmo ../stdlib/string.cmo ../stdlib/list.cmo \
     ../stdlib/filename.cmo ext_string.cmo
 ext_list.cmo : ../stdlib/list.cmi ../stdlib/array.cmi
 ext_list.cmo : ../stdlib/list.cmo ../stdlib/array.cmo
-ext_string.cmo : ../stdlib/string.cmi
-ext_string.cmo : ../stdlib/string.cmo
+ext_string.cmo : ../stdlib/string.cmi ../stdlib/bytes.cmi
+ext_string.cmo : ../stdlib/string.cmo ../stdlib/bytes.cmo
 fib.cmo :
 fib.cmo :
 for_loop_test.cmo : mt.cmo ../stdlib/list.cmi ../stdlib/array.cmi

jscomp/test/ext_string.d.ts

@@ -3,4 +3,5 @@ export var split_by: ($staropt$star : any, is_delim : any, str : any) => any
 export var split: (keep_empty : any, str : any, on : any) => any ;
 export var starts_with: (s : any, beg : any) => any ;
 export var ends_with: (s : any, beg : any) => any ;
+export var escaped: (s : any) => any ;
 

jscomp/test/ext_string.js

@@ -1,5 +1,6 @@
 // Generated CODE, PLEASE EDIT WITH CARE
 "use strict";
+var Bytes = require("../stdlib/bytes");
 var $$String = require("../stdlib/string");
 
 function split_by($staropt$star, is_delim, str) {
@@ -89,8 +90,46 @@ function ends_with(s, beg) {
   }
 }
 
+function escaped(s) {
+  var needs_escape = function (_i) {
+    while(/* true */1) {
+      var i = _i;
+      if (i >= s.length) {
+        return /* false */0;
+      }
+      else {
+        var match = s.charCodeAt(i);
+        if (match >= 32) {
+          var switcher = -34 + match;
+          if (!(58 < (switcher >>> 0))) {
+            if (56 < (-1 + switcher >>> 0)) {
+              return /* true */1;
+            }
+            else {
+              _i = i + 1;
+            }
+          }
+          else {
+            if (switcher >= 93) {
+              return /* true */1;
+            }
+            else {
+              _i = i + 1;
+            }
+          }
+        }
+        else {
+          return match >= 11 ? (match !== 13, /* true */1) : (match >= 8, /* true */1);
+        }
+      }
+    };
+  };
+  return needs_escape(0) ? Bytes.unsafe_to_string(Bytes.escaped(Bytes.unsafe_of_string(s))) : s;
+}
+
 exports.split_by = split_by;
 exports.split = split;
 exports.starts_with = starts_with;
 exports.ends_with = ends_with;
+exports.escaped = escaped;
 /* No side effect */