[brace-fold addon] Add a brace-paren folding helper

Closes codemirror#6868

Author: marijnh

addon/fold/brace-fold.js

@@ -11,58 +11,67 @@
 })(function(CodeMirror) {
 "use strict";
 
-CodeMirror.registerHelper("fold", "brace", function(cm, start) {
- var line = start.line, lineText = cm.getLine(line);
+function bracketFolding(pairs) {
+ return function(cm, start) {
+ var line = start.line, lineText = cm.getLine(line);
 
- function findOpening(openCh) {
- var tokenType;
- for (var at = start.ch, pass = 0;;) {
- var found = at <= 0 ? -1 : lineText.lastIndexOf(openCh, at - 1);
- if (found == -1) {
- if (pass == 1) break;
- pass = 1;
- at = lineText.length;
- continue;
+ function findOpening(pair) {
+ var tokenType;
+ for (var at = start.ch, pass = 0;;) {
+ var found = at <= 0 ? -1 : lineText.lastIndexOf(pair[0], at - 1);
+ if (found == -1) {
+ if (pass == 1) break;
+ pass = 1;
+ at = lineText.length;
+ continue;
+ }
+ if (pass == 1 && found < start.ch) break;
+ tokenType = cm.getTokenTypeAt(CodeMirror.Pos(line, found + 1));
+ if (!/^(comment|string)/.test(tokenType)) return {ch: found + 1, tokenType: tokenType, pair: pair};
+ at = found - 1;
  }
- if (pass == 1 && found < start.ch) break;
- tokenType = cm.getTokenTypeAt(CodeMirror.Pos(line, found + 1));
- if (!/^(comment|string)/.test(tokenType)) return {ch: found + 1, tokenType: tokenType};
- at = found - 1;
  }
- }
 
- function findRange(startToken, endToken, found) {
- var count = 1, lastLine = cm.lastLine(), end, startCh = found.ch, endCh
- outer: for (var i = line; i <= lastLine; ++i) {
- var text = cm.getLine(i), pos = i == line ? startCh : 0;
- for (;;) {
- var nextOpen = text.indexOf(startToken, pos), nextClose = text.indexOf(endToken, pos);
- if (nextOpen < 0) nextOpen = text.length;
- if (nextClose < 0) nextClose = text.length;
- pos = Math.min(nextOpen, nextClose);
- if (pos == text.length) break;
- if (cm.getTokenTypeAt(CodeMirror.Pos(i, pos + 1)) == found.tokenType) {
- if (pos == nextOpen) ++count;
- else if (!--count) { end = i; endCh = pos; break outer; }
+ function findRange(found) {
+ var count = 1, lastLine = cm.lastLine(), end, startCh = found.ch, endCh
+ outer: for (var i = line; i <= lastLine; ++i) {
+ var text = cm.getLine(i), pos = i == line ? startCh : 0;
+ for (;;) {
+ var nextOpen = text.indexOf(found.pair[0], pos), nextClose = text.indexOf(found.pair[1], pos);
+ if (nextOpen < 0) nextOpen = text.length;
+ if (nextClose < 0) nextClose = text.length;
+ pos = Math.min(nextOpen, nextClose);
+ if (pos == text.length) break;
+ if (cm.getTokenTypeAt(CodeMirror.Pos(i, pos + 1)) == found.tokenType) {
+ if (pos == nextOpen) ++count;
+ else if (!--count) { end = i; endCh = pos; break outer; }
+ }
+ ++pos;
  }
- ++pos;
  }
- }
 
- if (end == null || line == end) return null
- return {from: CodeMirror.Pos(line, startCh),
- to: CodeMirror.Pos(end, endCh)};
- }
+  if (end == null || line == end) return null
+  return {from: CodeMirror.Pos(line, startCh),
+  to: CodeMirror.Pos(end, endCh)};
+  }
 
- var startBrace = findOpening("{"), startBracket = findOpening("[")
- if (startBrace && (!startBracket || startBracket.ch > startBrace.ch)) {
- return findRange("{", "}", startBrace) || (startBracket && findRange("[", "]", startBracket))
- } else if (startBracket) {
- return findRange("[", "]", startBracket) || (startBrace && findRange("{", "}", startBrace))
- } else {
+ var found = []
+ for (var i = 0; i < pairs.length; i++) {
+ var open = findOpening(pairs[i])
+ if (open) found.push(open)
+ }
+ found.sort(function(a, b) { return a.ch - b.ch })
+ for (var i = 0; i < found.length; i++) {
+ var range = findRange(found[i])
+ if (range) return range
+ }
  return null
  }
-});
+}
+
+CodeMirror.registerHelper("fold", "brace", bracketFolding([["{", "}"], ["[", "]"]]));
+
+CodeMirror.registerHelper("fold", "brace-paren", bracketFolding([["{", "}"], ["[", "]"], ["(", ")"]]));
 
 CodeMirror.registerHelper("fold", "import", function(cm, start) {
  function hasImport(line) {

mode/commonlisp/commonlisp.js

@@ -114,6 +114,7 @@ CodeMirror.defineMode("commonlisp", function (config) {
 
  closeBrackets: {pairs: "()[]{}\"\""},
  lineComment: ";;",
+ fold: "brace-paren",
  blockCommentStart: "#|",
  blockCommentEnd: "|#"
  };

mode/scheme/scheme.js

@@ -273,6 +273,7 @@ CodeMirror.defineMode("scheme", function () {
  return state.indentStack.indent;
  },
 
+ fold: "brace-paren",
  closeBrackets: {pairs: "()[]{}\"\""},
  lineComment: ";;"
  };