blob: 7c39359d0ed16b224946239d40693435b2c7944f [file] [log] [blame]
// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
/**
* @fileoverview Parses the output format.
*/
export class OutputFormatTree {
value = '';
firstChild?: OutputFormatTree;
nextSibling?: OutputFormatTree;
parent?: OutputFormatTree;
private constructor() {}
static parseFormat(format: string | OutputFormatTree): OutputFormatTree[] {
let formatTrees: OutputFormatTree[] = [];
// Hacky way to support args.
if (typeof (format) === 'string') {
format = format.replace(/([,:])\s+/gm, '$1');
const words = format.split(' ');
// Ignore empty strings.
words.filter(word => Boolean(word));
formatTrees = words.map(word => OutputFormatTree.buildFromString_(word));
} else if (format) {
formatTrees = [format];
}
return formatTrees;
}
/** Parses the token containing a custom function and returns a tree. */
private static buildFromString_(inputStr: string): OutputFormatTree {
const root = new OutputFormatTree();
let currentNode: OutputFormatTree = root;
let index = 0;
let braceNesting = 0;
while (index < inputStr.length) {
if (inputStr[index] === '(') {
currentNode.firstChild = new OutputFormatTree();
currentNode.firstChild.parent = currentNode;
currentNode = currentNode.firstChild;
} else if (inputStr[index] === ')') {
// TODO(b/314203187): Not null asserted, check that this is correct.
currentNode = currentNode.parent!;
} else if (inputStr[index] === '{') {
braceNesting++;
currentNode.value += inputStr[index];
} else if (inputStr[index] === '}') {
braceNesting--;
currentNode.value += inputStr[index];
} else if (inputStr[index] === ',' && braceNesting === 0) {
currentNode.nextSibling = new OutputFormatTree();
currentNode.nextSibling.parent = currentNode.parent;
currentNode = currentNode.nextSibling;
} else if (inputStr[index] === ' ' || inputStr[index] === '\n') {
// Ignored.
} else {
currentNode.value += inputStr[index];
}
index++;
}
if (currentNode !== root) {
throw 'Unbalanced parenthesis: ' + inputStr;
}
return root;
}
}