function parseFilters()

in assets/js/vue.js [6829:6909]
66 lines of code
38 McCabe index (conditional complexity)

  function parseFilters (exp) {
    var inSingle = false;
    var inDouble = false;
    var inTemplateString = false;
    var inRegex = false;
    var curly = 0;
    var square = 0;
    var paren = 0;
    var lastFilterIndex = 0;
    var c, prev, i, expression, filters;

    for (i = 0; i < exp.length; i++) {
      prev = c;
      c = exp.charCodeAt(i);
      if (inSingle) {
        if (c === 0x27 && prev !== 0x5C) { inSingle = false; }
      } else if (inDouble) {
        if (c === 0x22 && prev !== 0x5C) { inDouble = false; }
      } else if (inTemplateString) {
        if (c === 0x60 && prev !== 0x5C) { inTemplateString = false; }
      } else if (inRegex) {
        if (c === 0x2f && prev !== 0x5C) { inRegex = false; }
      } else if (
        c === 0x7C && // pipe
        exp.charCodeAt(i + 1) !== 0x7C &&
        exp.charCodeAt(i - 1) !== 0x7C &&
        !curly && !square && !paren
      ) {
        if (expression === undefined) {
          // first filter, end of expression
          lastFilterIndex = i + 1;
          expression = exp.slice(0, i).trim();
        } else {
          pushFilter();
        }
      } else {
        switch (c) {
          case 0x22: inDouble = true; break         // "
          case 0x27: inSingle = true; break         // '
          case 0x60: inTemplateString = true; break // `
          case 0x28: paren++; break                 // (
          case 0x29: paren--; break                 // )
          case 0x5B: square++; break                // [
          case 0x5D: square--; break                // ]
          case 0x7B: curly++; break                 // {
          case 0x7D: curly--; break                 // }
        }
        if (c === 0x2f) { // /
          var j = i - 1;
          var p = (void 0);
          // find first non-whitespace prev char
          for (; j >= 0; j--) {
            p = exp.charAt(j);
            if (p !== ' ') { break }
          }
          if (!p || !validDivisionCharRE.test(p)) {
            inRegex = true;
          }
        }
      }
    }

    if (expression === undefined) {
      expression = exp.slice(0, i).trim();
    } else if (lastFilterIndex !== 0) {
      pushFilter();
    }

    function pushFilter () {
      (filters || (filters = [])).push(exp.slice(lastFilterIndex, i).trim());
      lastFilterIndex = i + 1;
    }

    if (filters) {
      for (i = 0; i < filters.length; i++) {
        expression = wrapFilter(expression, filters[i]);
      }
    }

    return expression
  }