Merge commit 'refs/pullreqs/211'

Author: osnr

lib/folk.js

@@ -1,10 +1,8 @@
 // const WHITESPACE = /^[ \t]+/;
 // const NEWLINE = /^[;\n]+/;
-const WORDSEP = /^[ \t;\n]+/;
+const WORDSEP = /^[ \t\n\r\f\v]+/;
 const QUOTED = /^".*?[^\\]"/;
-const WORD = /^([^ \t;\n{}[\]"\\]|\\[ \t;\n{}[\]"\\])+/;
-const ESCAPED = /\\(.)/g;
-const ESCAPABLE = /([ \t;\n{}[\]"])/g;
+const WORD = /^([^ \t\n\r\f\v{}\\]|\\.)+/;
 
 const eat = (regex, str) => {
   const match = str.match(regex);
@@ -34,26 +32,84 @@ const eatBrace = (str) => {
 };
 
 const checkBrace = (str) => {
-  let bc = 0;
-  let bk = 0;
+  let curlies = 0;
+  let brackets = 0;
   const l = str.length;
   for (let i = 0; i < l; i++) {
     switch (str[i]) {
-      case '{': bc++; break;
-      case '}': bc--; break;
-      case '[': bk++; break;
-      case ']': bk--; break;
+      case '{': curlies++; break;
+      case '}': curlies--; break;
+      case '[': brackets++; break;
+      case ']': brackets--; break;
+    }
+
+    if (curlies < 0) return false;
+  }
+
+  return curlies === 0 && brackets >= 0;
+};
+
+// ported from JimEscape in jim.c
+const UNESCAPE_TABLE = {
+  'a': '\a',
+  'b': '\b',
+  'n': '\n',
+  'r': '\r',
+  't': '\t',
+  'f': '\f',
+  'v': '\v',
+  '0': '\x00',
+};
+
+const unescape = (str) => {
+  let output = "";
+
+  for (let i = 0; i < str.length; i++) {
+    // used to prevent out-of-bounds issues with `str[i + 1]`
+    if (i === str.length - 1) {
+      output += str[i];
+      break;
     }
 
-    if (bc < 0) return false;
-    if (bk < 0) return false;
+    if (str[i] === '\\') {
+      // is the next character escapable?
+      const unescaped = UNESCAPE_TABLE[str[i + 1]];
+      if (unescaped) {
+        output += unescaped;
+      } else {
+        // else just append it, sans the backslash
+        output += str[i + 1];
+      }
+
+      i++;
+      // TODO: octal, \x \u \U \u{NNN}
+    } else {
+      output += str[i];
+    }
   }
 
-  return bc === 0 && bk === 0;
+  return output;
+};
+
+// ported from BackslashQuoteString in jim.c
+const ESCAPE_TABLE = {
+  ' ': '\\ ',
+  '$': '\\$',
+  '"': '\\"',
+  '[': '\\[',
+  ']': '\\]',
+  '{': '\\{',
+  '}': '\\}',
+  ';': '\\;',
+  '\\': '\\\\',
+  '\n': '\\n',
+  '\r': '\\r',
+  '\t': '\\t',
+  '\f': '\\f',
+  '\v': '\\v',
 };
 
-const unescape = (str) => str.replaceAll(ESCAPED, '$1');
-const escape = (str) => str.replaceAll(ESCAPABLE, '\\$1');
+const escape = (str) => str.split("").map(char => char in ESCAPE_TABLE ? ESCAPE_TABLE[char] : char).join("");
 
 // deserializtion
 const nextToken = (str) => {
@@ -69,14 +125,19 @@ const nextToken = (str) => {
       case ' ':
       case '\t':
       case '\n':
-      case ';':
+      case '\r':
+      case '\f':
+      case '\v':
         return [token, str];
 
-      case '[':
-        throw new Error("this aint no interpreter");
       case '{':
         [word, str] = eatBrace(str);
-        token += word.slice(1, -1);
+
+        if (token === '') {
+          token = word.slice(1, -1);
+        } else {
+          token += word;
+        }
         break;
       case '"':
         [word, str] = eat(QUOTED, str);
@@ -127,8 +188,13 @@ const loadDict = (str) => {
 const dumpString = (word) => {
   if (!word.length) return '{}';
   const match = word.match(WORD);
-  if (match && match[0] === word) return word;
-  if (checkBrace(word)) return `{${word}}`;
+  if (word[0] !== "#" && match && match[0] === word) return word;
+  if (checkBrace(word)) {
+    // the one case that we can't handle with braces is a linefeed escape
+    if (!(/\\\n/.test(word))) {
+      return `{${word}}`;
+    }
+  }
   return escape(word);
 }
 
@@ -280,7 +346,7 @@ class FolkWS {
     const channel = this.createChannel((message) => {
       const [action, match, matchId] = loadList(message);
       const callback = callbacks[action];
-      callback && callback(loadDict(match), matchId);
+      if (callback) callback(loadDict(match), matchId);
     });
 
     const retractKey = await this.send(tcl`