Apex Log Indenter - Add indents to Apex logs files to make them easier to read and navigate.

<io-app> apex-log-indenter.js

/**
 * Responsible for producing the first half of the page all the way up to but
 * not including the output.  All of the elements produced by this function
 * serve display purposes and input purposes.
 * @param data {Object}
 *   An object mainly representing the input data.
 * @returns {Array=}
 *   An array of objects that represent the elements that will be shown in the
 *   input section of the page.  If nothing is returned, the input section will
 *   not be updated
 */
function getInputs(data) {
  return [
    { type: 'uploadable-text', id: 'txtContents', rows: 20 },
    {
      type: 'div',
      className: 'text-center',
      children: [
        {
          type: 'button',
          text: 'Indent',
          disabled: !data.valuesById.txtContents,
          id: 'btnIndent'
        }
      ]
    }
  ];
}


/**
 * Responsible for producing the second half of the page which starts after the
 * input section and goes to the end of the page.  All of the elements produced
 * by this function only serve display purposes.
 * @param data {Object}
 *   An object mainly representing the input data.
 * @returns {Array=}
 *   An array of objects that represent the elements that will be shown in the
 *   output section of the page.  If nothing is returned, the output section
 *   will not be updated.
 */
function getOutputs(data) {
  if (data.clickedButtonId === 'btnIndent') {
    return [
      {
        type: 'downloadable-text',
        value: indentApexLog(data.valuesById.txtContents),
        rows: 20,
        downloadName: (data.filesById.txtContents || {}).name || 'download.txt'
      }
    ];
  }
}

indentApexLog.js

// Used by indentApexLog() to figure out when indentation should start and end.
var RGX_HEADER = /^[\d:\.]+\s*\(\w+\)\|(?:(CODE_UNIT_STARTED|\w+_ENTRY)|(CODE_UNIT_FINISHED|\w+_EXIT))\|/;

/**
 * Indents the specified contents of an Apex file to make it easier to navigate
 * within an IDE that has a tree-view whenever indentation is added.
 * @param contents {string}
 *   The contents of the Apex log file.
 * @returns {string}
 *   The contents with proper indentation whenever code units start and end and
 *   whenever other things have an ENTRY and an EXIT.
 */
function indentApexLog(contents) {
  var indentation = "";
  return contents.split(/\r?\n|\r/).map(function(line) {
    var m = RGX_HEADER.exec(line) || [];
    if (m[2]) {
      indentation = indentation.slice(1)
    }
    line = indentation + line;
    if (m[1]) {
      indentation += "\t";
    }
    return line;
  }).join('\n');
}

index.jsonc

// Every YourJS IO App must be able to either find index.json or index.jsonc in the Gist.
{
  "title": "Apex Log Indenter",
  "description": "Add indents to Apex logs files to make them easier to read and navigate.",
  "js": [
    "<io-app> apex-log-indenter.js",
    "indentApexLog.js"
  ],
  "css": []
}

~io-config.jsonc

{
  // Name of the function responsable for transforming the input into the output.
  "transform": "indentApexLog",
  // Where to find the code that will be eval'd.
  "files": ["indentApexLog.js"],
  // Input setup
  "input": { "label": "Log File Contents" },
  // Output setup
  "output": { "label": "Formatted Log File Contents" },
  // Type of YourJS IO-App
  "type": "split"
}

Here is the IO App:
https://www.yourjs.com/gist-io/088682af25f978c08aaf303ac8c95f40