Align ReScript string escapes with JS strict-mode

.depend

@@ -2,8 +2,8 @@ src/reactjs_jsx_ppx_v3.cmx : src/reactjs_jsx_ppx_v3.cmi
 src/reactjs_jsx_ppx_v3.cmi :
 src/res_ast_conversion.cmx : src/res_printer.cmx src/res_ast_conversion.cmi
 src/res_ast_conversion.cmi :
-src/res_ast_debugger.cmx : src/res_driver.cmx src/res_doc.cmx \
-    src/res_ast_debugger.cmi
+src/res_ast_debugger.cmx : src/res_string.cmx src/res_driver.cmx \
+    src/res_doc.cmx src/res_ast_debugger.cmi
 src/res_ast_debugger.cmi : src/res_driver.cmi
 src/res_cli.cmx : src/res_driver_reason_binary.cmx \
     src/res_driver_ml_parser.cmx src/res_driver_binary.cmx src/res_driver.cmx \
@@ -61,7 +61,7 @@ src/res_parser.cmi : src/res_token.cmx src/res_scanner.cmi \
     src/res_comment.cmi
 src/res_parsetree_viewer.cmx : src/res_parsetree_viewer.cmi
 src/res_parsetree_viewer.cmi :
-src/res_printer.cmx : src/res_utf8.cmx src/res_token.cmx \
+src/res_printer.cmx : src/res_utf8.cmx src/res_token.cmx src/res_string.cmx \
     src/res_parsetree_viewer.cmx src/res_parens.cmx src/res_doc.cmx \
     src/res_comments_table.cmx src/res_comment.cmx src/res_printer.cmi
 src/res_printer.cmi : src/res_doc.cmi src/res_comments_table.cmx \
@@ -70,6 +70,8 @@ src/res_reporting.cmx : src/res_token.cmx src/res_grammar.cmx
 src/res_scanner.cmx : src/res_utf8.cmx src/res_token.cmx \
     src/res_diagnostics.cmx src/res_comment.cmx src/res_scanner.cmi
 src/res_scanner.cmi : src/res_token.cmx src/res_diagnostics.cmi
+src/res_string.cmx : src/res_string.cmi
+src/res_string.cmi :
 src/res_token.cmx : src/res_comment.cmx
 src/res_utf8.cmx : src/res_utf8.cmi
 src/res_utf8.cmi :

Makefile

@@ -13,6 +13,7 @@ depend:
 API_FILES = \
 	src/reactjs_jsx_ppx_v3.cmx\
 	src/res_io.cmx\
+	src/res_string.cmx\
 	src/res_minibuffer.cmx\
 	src/res_doc.cmx\
 	src/res_comment.cmx\
@@ -46,7 +47,7 @@ TEST_FILES = $(API_FILES) tests/res_utf8_test.cmx tests/res_test.cmx
 .DEFAULT_GOAL := build-native
 
 lib/rescript.exe: $(CLI_FILES)
-	$(OCAMLOPT) $(OCAMLFLAGS) -O2 -o ./lib/rescript.exe -I +compiler-libs ocamlcommon.cmxa  -I src $(CLI_FILES)
+	$(OCAMLOPT) $(OCAMLFLAGS) -O2 -o ./lib/rescript.exe -I +compiler-libs ocamlcommon.cmxa str.cmxa  -I src $(CLI_FILES)
 
 build-native: lib/refmt.exe lib/rescript.exe depend
 
@@ -69,7 +70,7 @@ benchmarks/refmt_main3b.cmx: benchmarks/refmt_main3b.ml
 	$(OCAMLOPT) -c -O2 -I +compiler-libs ocamlcommon.cmxa benchmarks/refmt_main3b.ml
 
 lib/test.exe: $(TEST_FILES)
-	$(OCAMLOPT) $(OCAMLFLAGS) -O2 -o ./lib/test.exe -bin-annot -I +compiler-libs ocamlcommon.cmxa -I src -I tests $(TEST_FILES)
+	$(OCAMLOPT) $(OCAMLFLAGS) -O2 -o ./lib/test.exe -bin-annot -I +compiler-libs ocamlcommon.cmxa str.cmxa -I src -I tests $(TEST_FILES)
 
 test: reanalyze build-native lib/test.exe
 	./lib/test.exe

src/res_ast_debugger.ml

@@ -154,7 +154,7 @@ module SexpAst = struct
     | Pconst_string (txt, tag) ->
       Sexp.list [
         Sexp.atom "Pconst_string";
-        string txt;
+        string (Res_string.convertDecEscapes txt);
         match tag with
         | Some txt -> Sexp.list [
             Sexp.atom "Some";

src/res_core.ml

@@ -142,8 +142,6 @@ type stringLiteralState =
   | Start
   | Backslash
   | HexEscape
-  | DecimalEscape
-  | OctalEscape
   | UnicodeEscape
   | UnicodeCodePointEscape
   | UnicodeEscapeStart
@@ -500,7 +498,7 @@ let parseStringLiteral s =
   let rec parse state i d =
     if i = len then
       (match state with
-      | HexEscape | DecimalEscape | OctalEscape | UnicodeEscape | UnicodeCodePointEscape -> false
+      | HexEscape | UnicodeEscape | UnicodeCodePointEscape -> false
       | _ -> true)
     else
       let c = String.unsafe_get s i in
@@ -515,11 +513,10 @@ let parseStringLiteral s =
         | 'r' -> Buffer.add_char b '\r'; parse Start (i + 1) d
         | 'b' -> Buffer.add_char b '\008'; parse Start (i + 1) d
         | 't' -> Buffer.add_char b '\009'; parse Start (i + 1) d
+        | '0' -> Buffer.add_char b '\000'; parse Start (i + 1) d
         | ('\\' | ' ' | '\'' | '"') as c -> Buffer.add_char b c; parse Start (i + 1) d
         | 'x' -> parse HexEscape (i + 1) 0
-        | 'o' -> parse OctalEscape (i + 1) 0
         | 'u' -> parse UnicodeEscapeStart (i + 1) 0
-        | '0' .. '9' -> parse DecimalEscape i 0
         | '\010' | '\013' -> parse EscapedLineBreak (i + 1) d
         | c -> Buffer.add_char b '\\'; Buffer.add_char b c; parse Start (i + 1) d)
       | HexEscape ->
@@ -534,32 +531,6 @@ let parseStringLiteral s =
           )
         else
           parse HexEscape (i + 1) (d + 1)
-      | DecimalEscape ->
-        if d == 2 then
-          let c0 = String.unsafe_get s (i - 2) in
-          let c1 = String.unsafe_get s (i - 1) in
-          let c2 = String.unsafe_get s i in
-          let c = 100 * (Char.code c0 - 48) + 10 * (Char.code c1  - 48) + (Char.code c2 - 48) in
-          if c < 0 || c > 255 then false
-          else (
-            Buffer.add_char b (Char.unsafe_chr c);
-            parse Start (i + 1) 0
-          )
-        else
-          parse DecimalEscape (i + 1) (d + 1)
-      | OctalEscape ->
-        if d == 2 then
-          let c0 = String.unsafe_get s (i - 2) in
-          let c1 = String.unsafe_get s (i - 1) in
-          let c2 = String.unsafe_get s i in
-          let c = 64 * (Char.code c0 - 48) + 8 * (Char.code c1  - 48) + (Char.code c2 - 48) in
-          if c < 0 || c > 255 then false
-          else (
-            Buffer.add_char b (Char.unsafe_chr c);
-            parse Start (i + 1) 0
-          )
-        else
-          parse OctalEscape (i + 1) (d + 1)
       | UnicodeEscapeStart ->
         (match c with
         | '{' -> parse UnicodeCodePointEscape (i + 1) 0

src/res_printer.ml

@@ -492,7 +492,7 @@ let printStringLoc sloc cmtTbl =
   printComments doc cmtTbl sloc.loc
 
 let printStringContents txt =
-  let lines = String.split_on_char '\n' txt in
+  let lines = String.split_on_char '\n' (Res_string.convertDecEscapes txt) in
   Doc.join ~sep:Doc.literalLine (List.map Doc.text lines)
 
 let printConstant ?(templateLiteral=false) c = match c with

src/res_scanner.ml

@@ -328,13 +328,22 @@ let scanStringEscapeSequence ~startPos scanner =
   (* \ already consumed *)
   | 'n' | 't' | 'b' | 'r' | '\\' | ' ' | '\'' | '"' ->
     next scanner
-  | '0'..'9' ->
-    (* decimal *)
-    scan ~n:3 ~base:10 ~max:255
-  | 'o' ->
-    (* octal *)
+  | '0' ->
     next scanner;
-    scan ~n:3 ~base:8 ~max:255
+    let nextCharIsDecimalDigit =
+      match scanner.ch with 
+      | '0' .. '9' -> true 
+      | _ -> false
+    in
+    if nextCharIsDecimalDigit then
+      let pos = position scanner in
+      let msg = "The only valid numeric escape in strict mode is '\\0'" in
+      scanner.err ~startPos ~endPos:pos (Diagnostics.message msg)
+  | '1'..'9' ->
+    let pos = position scanner in
+    let msg = "The only valid numeric escape in strict mode is '\\0'" in
+    scanner.err ~startPos ~endPos:pos (Diagnostics.message msg);
+    next scanner
   | 'x' ->
     (* hex *)
     next scanner;

src/res_string.ml

@@ -0,0 +1,14 @@
+let hexTable = [|'0'; '1'; '2'; '3'; '4'; '5'; '6'; '7'; '8'; '9'; 'a'; 'b'; 'c'; 'd'; 'e'; 'f'|]
+
+let convertDecEscapes txt =
+  let regex = Str.regexp "\\\\[0-9][0-9][0-9]" in
+  let convertEscape s =
+    let strNum = Str.string_after (Str.matched_string s) 1 in
+    try
+      let intNum = int_of_string strNum in
+      let c1 = Array.get hexTable (intNum lsr 4) in
+      let c2 = Array.get hexTable (intNum land 15) in
+      "\\x" ^ String.concat "" [ String.make 1 c1; String.make 1 c2 ]
+    with _ -> s (* in theory this should never happen *)
+  in
+  Str.global_substitute regex convertEscape txt

src/res_string.mli

@@ -0,0 +1 @@
+val convertDecEscapes: string -> string

test.sh

@@ -23,6 +23,7 @@ done
 
 # printing
 for file in tests/{printer,conversion}/**/*.(res|resi|ml|mli); do
+  # NOTE: this results in .ml(i) files being printed using .res(i) syntax
   lib/rescript.exe $file &> $(exp $file) & maybeWait
 done
 for file in tests/{printer,conversion}/**/*.re; do

tests/parsing/errors/expressions/expected/stringLiteral.res.txt

@@ -0,0 +1,24 @@
+
+  Syntax error!
+  tests/parsing/errors/expressions/stringLiteral.res:2:4-5
+
+  1 │ switch x {
+  2 │ | "\055" => ()
+  3 │ | "\123" => ()
+  4 │ }
+
+  The only valid numeric escape in strict mode is '\0'
+
+
+  Syntax error!
+  tests/parsing/errors/expressions/stringLiteral.res:3:4
+
+  1 │ switch x {
+  2 │ | "\055" => ()
+  3 │ | "\123" => ()
+  4 │ }
+  5 │ 
+
+  The only valid numeric escape in strict mode is '\0'
+
+;;match x with | {js|\055|js} -> () | {js|\123|js} -> ()

tests/parsing/errors/expressions/object.res

@@ -0,0 +1 @@
+let obj = {"\055": "octal escape", "\123": "another octal escape"}

tests/parsing/errors/expressions/stringLiteral.res

@@ -0,0 +1,4 @@
+switch x {
+| "\055" => ()
+| "\123" => ()
+}

tests/parsing/errors/scanner/escapeSequence.res

@@ -1,3 +1,3 @@
-let x = "\0"
+let x = "\055"
 
-let x = "\oAAA"
+let x = "\123"

tests/parsing/errors/scanner/expected/escapeSequence.res.txt

@@ -2,22 +2,22 @@
   Syntax error!
   tests/parsing/errors/scanner/escapeSequence.res:1:10-11
 
-  1 │ let x = "\0"
+  1 │ let x = "\055"
   2 │ 
-  3 │ let x = "\oAAA"
+  3 │ let x = "\123"
 
-  unknown escape sequence
+  The only valid numeric escape in strict mode is '\0'
 
 
   Syntax error!
-  tests/parsing/errors/scanner/escapeSequence.res:3:10-11
+  tests/parsing/errors/scanner/escapeSequence.res:3:10
 
-  1 │ let x = "\0"
+  1 │ let x = "\055"
   2 │ 
-  3 │ let x = "\oAAA"
+  3 │ let x = "\123"
   4 │ 
 
-  unknown escape sequence
+  The only valid numeric escape in strict mode is '\0'
 
-let x = {js|\0|js}
-let x = {js|\oAAA|js}
+let x = {js|\055|js}
+let x = {js|\123|js}

tests/parsing/grammar/expressions/bsObject.res

@@ -1,7 +1,10 @@
+let zero = 0
+
 let x = {"age": 30}
 let y = {"age": 30,}
 let y = {"age": 30, "name": "steve"}
 let y = {"age": 30, "name": "steve",}
+let z = {"\xff": 1, "\u2212": "two", "\0": zero, "\o123": "o123"}
 
 // don't confuse with start of block expr
 let x = {"age"}

tests/parsing/grammar/expressions/constants.res

@@ -56,18 +56,15 @@ let x = '\t'
 let x = '\b'
 let x = '\r'
 let x = ' '
-let x = '\o021'
 let x = '\xAA'
-let x = '\179'
 
 let () = {
   getResult()
   -10
 }
 
-let x = "foo\010bar"
+let x = "foo\0bar"
 let x = "foo\x0Abar"
-let x = "foo\o012bar"
 let x = "\\abc"
 let x = "\'bar"
 let x = "\nbar"
@@ -81,13 +78,13 @@ let x = "\u2665"
 let a = "\u{000000000061}"
 let x = "\u{00A9}"
 let x = "\u{00a9}"
+let x = "\oAAA" // same as "oAAA" since \o is not a valid escape
+let x = "\m" // same as "m" since \m is not a valid escape
 let smile = "\u{1F600}"
 let smile = "\u{1f600}"
-let smile = "\240\159\152\128"
 
 // represent the same thing
 let u = "日本語" 
 let u = "\u65e5\u672c\u8a9e"
 let u = "\u{000065e5}\u{0000672c}\u{00008a9e}"
 let u = "\xe6\x97\xa5\xe6\x9c\xac\xe8\xaa\x9e"
-let u = "\230\151\165\230\156\172\232\170\158"

tests/parsing/grammar/expressions/expected/bsObject.res.txt

@@ -1,7 +1,10 @@
+let zero = 0
 let x = [%obj { age = 30 }]
 let y = [%obj { age = 30 }]
 let y = [%obj { age = 30; name = {js|steve|js} }]
 let y = [%obj { age = 30; name = {js|steve|js} }]
+let z =
+  [%obj { � = 1; \u2212 = {js|two|js}; \0 = zero; \o123 = {js|o123|js} }]
 let x = (("age")[@ns.braces ])
 let x = (("age".(0))[@ns.braces ])
 let x = (("age" |. Js.log)[@ns.braces ])

tests/parsing/grammar/expressions/expected/constants.res.txt

@@ -46,13 +46,10 @@ let x = '\t'
 let x = '\b'
 let x = '\r'
 let x = ' '
-let x = '\017'
 let x = '\170'
-let x = '\179'
 let () = ((getResult (); (-10))[@ns.braces ])
-let x = {js|foo\010bar|js}
+let x = {js|foo\0bar|js}
 let x = {js|foo\x0Abar|js}
-let x = {js|foo\o012bar|js}
 let x = {js|\\abc|js}
 let x = {js|\'bar|js}
 let x = {js|\nbar|js}
@@ -66,11 +63,11 @@ let x = {js|\u2665|js}
 let a = {js|\u{000000000061}|js}
 let x = {js|\u{00A9}|js}
 let x = {js|\u{00a9}|js}
+let x = {js|\oAAA|js}
+let x = {js|\m|js}
 let smile = {js|\u{1F600}|js}
 let smile = {js|\u{1f600}|js}
-let smile = {js|\240\159\152\128|js}
 let u = {js|日本語|js}
 let u = {js|\u65e5\u672c\u8a9e|js}
 let u = {js|\u{000065e5}\u{0000672c}\u{00008a9e}|js}
-let u = {js|\xe6\x97\xa5\xe6\x9c\xac\xe8\xaa\x9e|js}
-let u = {js|\230\151\165\230\156\172\232\170\158|js}
+let u = {js|\xe6\x97\xa5\xe6\x9c\xac\xe8\xaa\x9e|js}

tests/parsing/grammar/pattern/constant.res

@@ -7,6 +7,10 @@ switch x {
 | "stringPattern" => ()
 | "stringPattern" as s => ()
 | ("stringPattern" : string) as s => ()
+| "\xff" => ()
+| "\u2212" => ()
+| "\0" => ()
+| "\o123" => ()
 }
 
 for "stringPattern" in 0 to 10 { () }

tests/parsing/grammar/pattern/expected/constant.res.txt

@@ -6,6 +6,10 @@ let ({js|stringPattern|js} : string) as s = ()
   | {js|stringPattern|js} -> ()
   | {js|stringPattern|js} as s -> ()
   | ({js|stringPattern|js} : string) as s -> ()
+  | {js|\xff|js} -> ()
+  | {js|\u2212|js} -> ()
+  | {js|\0|js} -> ()
+  | {js|\o123|js} -> ()
 ;;for {js|stringPattern|js} = 0 to 10 do () done
 ;;for {js|stringPattern|js} as s = 0 to 10 do () done
 ;;for {js|stringPattern|js} = 0 to 10 do () done