escape LineTerminator in escape sequences template literal characters (#118)

Interprets escape sequences in template characters as specified in:
https://tc39.es/ecma262/#prod-TemplateCharacter

The "LineTerminator" is part of "NonEscapeCharacter" in a "EscapeSequence"

If you want to use line breaks to make your source code easier to read, but you don’t want the line breaks to be part of the string’s value, write a backslash () at the end of those line.

Author: IwanKaramazow

.depend

@@ -13,7 +13,8 @@ src/res_comments_table.cmx : src/res_parsetree_viewer.cmx src/res_doc.cmx \
     src/res_comment.cmx
 src/res_core.cmx : src/res_token.cmx src/res_scanner.cmx src/res_printer.cmx \
     src/res_parser.cmx src/res_js_ffi.cmx src/res_grammar.cmx src/res_doc.cmx \
-    src/res_diagnostics.cmx src/res_comments_table.cmx src/res_core.cmi
+    src/res_diagnostics.cmx src/res_comments_table.cmx \
+    src/res_character_codes.cmx src/res_core.cmi
 src/res_core.cmi : src/res_parser.cmi
 src/res_diagnostics.cmx : src/res_token.cmx src/res_grammar.cmx \
     src/res_diagnostics_printing_utils.cmx src/res_diagnostics.cmi

src/res_character_codes.ml

@@ -157,4 +157,4 @@ let digitValue ch =
   else if Lower.a <= (lower ch) && (lower ch) <= Lower.f then
     (lower ch) - Lower.a + 10
   else
-    16 (* larger than any legal value *)
+    16 (* larger than any legal value *)

src/res_core.ml

@@ -838,6 +838,8 @@ let parseTemplateStringLiteral s =
           | '`' as c ->
             Buffer.add_char b c;
             loop (i + 2)
+          | c when Res_character_codes.isLineBreak (Char.code c) ->
+            loop (i + 2)
           | c ->
             Buffer.add_char b '\\';
             Buffer.add_char b c;

src/res_scanner.ml

@@ -432,6 +432,7 @@ let scanTemplateLiteralToken scanner =
       if scanner.ch == CharacterCodes.backtick
         || scanner.ch == CharacterCodes.backslash
         || scanner.ch == CharacterCodes.dollar
+        || CharacterCodes.isLineBreak scanner.ch
       then next scanner;
       scan()
     ) else (

tests/conversion/reason/__snapshots__/render.spec.js.snap

@@ -1276,6 +1276,9 @@ let x = 1
 
 exports[`string.re 1`] = `
 "%%bs.raw(\\"define(x.y, 'userAgent', {value: 'USER_AGENT_STRING'})\\")
+
+let x = \`This is a long string with a slash and line break \\\\\\\\
+carriage return\`
 "
 `;
 

tests/conversion/reason/string.re

@@ -1,2 +1,5 @@
 %bs.raw
 "define(x.y, 'userAgent', {value: 'USER_AGENT_STRING'})";
+
+let x = {js|This is a long string with a slash and line break \
+carriage return|js}