escape data strings according to WebAssembly spec , Fixes #37

src/ir/text.ml

@@ -16,6 +16,28 @@ type indice =
 
 let pp_id fmt id = pf fmt "$%s" id
 
+let pp_name_inner fmt s =
+  let pp_hex_char fmt c = pf fmt "\\%02x" (Char.code c) in
+  let pp_char fmt = function
+    | '\n' -> string fmt "\\n"
+    | '\r' -> string fmt "\\r"
+    | '\t' -> string fmt "\\t"
+    | '\'' -> string fmt "\\'"
+    | '"' -> string fmt "\\\""
+    | '\\' -> string fmt "\\\\"
+    | c ->
+      let ci = Char.code c in
+      if 0x20 <= ci && ci < 0x7f then char fmt c else pp_hex_char fmt c
+  in
+  let pp_unicode_char fmt = function
+    | (0x09 | 0x0a) as c -> pp_char fmt (Char.chr c)
+    | uc when 0x20 <= uc && uc < 0x7f -> pp_char fmt (Char.chr uc)
+    | uc -> pf fmt "\\u{%02x}" uc
+  in
+  String.iter (fun c -> pp_unicode_char fmt (Char.code c)) s
+
+let pp_name fmt s = pf fmt {|"%a"|} pp_name_inner s
+
 let pp_id_opt fmt = function None -> () | Some i -> pf fmt " %a" pp_id i
 
 let pp_indice fmt = function Raw u -> int fmt u | Text i -> pp_id fmt i
@@ -761,7 +783,7 @@ module Data = struct
     }
 
   let pp fmt (d : t) =
-    pf fmt {|(data%a %a %S)|} pp_id_opt d.id Mode.pp d.mode d.init
+    pf fmt {|(data%a %a %a)|} pp_id_opt d.id Mode.pp d.mode pp_name d.init
 end
 
 module Tag = struct

test/fmt/data_bytes.wat

@@ -0,0 +1,4 @@
+(module
+  (memory 1)
+  (data (i32.const 0) "Hello\00World\01\02\03\ff")
+)

test/fmt/data_roundtrip.t

@@ -0,0 +1,8 @@
+test data special chars round-trip:
+  $ owi fmt data_special_chars.wat > /tmp/owi_test_output.wat
+  $ owi fmt /tmp/owi_test_output.wat
+  (module
+    (memory 1)
+    (data (memory 0) (offset i32.const 0) "hello\n\t\u{0d}\"\'\\world")
+  )
+  $ rm /tmp/owi_test_output.wat

test/fmt/data_special_chars.wat

@@ -0,0 +1,4 @@
+(module
+  (memory 1)
+  (data (i32.const 0) "hello\n\t\r\"'\\world")
+)

test/fmt/dune

@@ -11,5 +11,7 @@
   m.wat
   locals.wat
   locals_drop.wat
+  data_special_chars.wat
+  data_bytes.wat
   script.wast
   script.t))

test/fmt/print.t

@@ -32,3 +32,15 @@ print simplified:
     )
     (start 1)
   )
+print data with special chars:
+  $ owi fmt data_special_chars.wat
+  (module
+    (memory 1)
+    (data (memory 0) (offset i32.const 0) "hello\n\t\u{0d}\"\'\\world")
+  )
+print data with raw bytes:
+  $ owi fmt data_bytes.wat
+  (module
+    (memory 1)
+    (data (memory 0) (offset i32.const 0) "Hello\u{00}World\u{01}\u{02}\u{03}\u{ff}")
+  )