objPath.js

/* -------------------- toPath -------------------- */
const toPath = (path = '') => {
  return String.prototype.replace
    .call(path, /\['(.+?)'\]/g, '.$1')
    .split(/[,[\].]+?/)
    .filter(Boolean);
}

/* --------------------- get --------------------- */
const get = (obj, path = '', defaultValue) => {
  const result = String.prototype.replace
    .call(path, /\['(.+?)'\]/g, '.$1')
    .split(/[,[\].]+?/)
    .filter(Boolean)
    .reduce(
      (res, key) => (res !== null && res !== undefined ? res[key] : res),
      obj
    );
  return result === undefined || result === obj ? defaultValue : result;
};


/* --------------------- has --------------------- */

// NOTE: two helper functions for has

// foo -->
// foo.bar --> foo
// foo.bar[3] --> foo.bar
// foo.bar.baz[2].raz.taz[5].laz --> foo.bar.baz[2].raz.taz[5]
const parentPath = (path) => {
  return `.${path}`.replace(/(.*)[.[].*/, '$1').replace(/\./, '');
}

// foo --> foo
// foo.bar --> bar
// foo.bar[3] --> [3]
// foo.bar.baz[2].raz.taz[5].laz --> laz
const pathKey = (path) => {
  return path.replace(parentPath(path), '').replace(/\./, '');
}

const has = (obj, path) => {
	const pPath = parentPath(path);
  const key = pathKey(path);
  // If we have parent path then get the object at that location
	// .. otherwise its the root object
  const parentObj = pPath ? get(obj, pPath) : obj;
	// If its [3] turn key into 3
  return !!(parentObj && Object.hasOwnProperty.call(parentObj, key.replace(/\[(.*)\]/, '$1')));
}


/* --------------------- set --------------------- */

const set = (obj, path = '', val) => {
  const result = String.prototype.replace
    .call(path, /\['(.+?)'\]/g, '.$1')
    .split(/[,[\].]+?/)
    .filter(Boolean)
    .reduce(
      (res, key, i, arr) => {
        //console.log('RES', res, 'Key', key, 'I', i, 'Arr', arr, 'OBJ', obj);
        // At the leaf set the value
        if( i === arr.length - 1){
          res[key] = val;
          return res[key];
        } 
        // Initialize to new array or object if needed
        if( res[key] === undefined ){
          if(Number.isInteger(+(arr[i+1]))) { 
						res[key] = [];
					} else {
						res[key] = {};
					}
          return res[key];
        }
        // Exception for if the value is changeing to an array
      	if (Number.isInteger(+arr[i + 1]) && !Array.isArray(res[key])) {
        	res[key] = [];
      	}
        // Otherwise keep whats there
        return res[key];
      },
      obj
    );
};


/* --------------------- unset --------------------- */

const unset = (obj, path = '') => {
  let found = false; 
  String.prototype.replace
    .call(path, /\['(.+?)'\]/g, '.$1')
    .split(/[,[\].]+?/)
    .filter(Boolean)
    .reduce(
      (res, key, i, arr) => {
        // Base case res is undefined 
        if(res === undefined){
          return res;
        }
        // At the leaf delete the value
        if( i === arr.length - 1){
          delete res[key];
          found = true;
          return res[key];
        } 
        // Otherwise keep going
        return res[key];
      },
      obj
    );
    return found;
};

/* --------------------- values --------------------- */

const values = (obj = {}) => {
  const props = Object.keys(obj);
  return props.map((key) => obj[key])
}

/* --------------------- pullAt --------------------- */

const pullAt = (obj, path = '') => {
  let pulled; 
  String.prototype.replace
    .call(path, /\['(.+?)'\]/g, '.$1')
    .split(/[,[\].]+?/)
    .filter(Boolean)
    .reduce(
      (res, key, i, arr) => {
        // Base case res is undefined 
        if(res === undefined){
          return res;
        }
        // At the leaf delete the value
        if( i === arr.length - 1 && Array.isArray(res)){
          // Pull out one value at index ( key )
          pulled = res.splice(key, 1);
          return res[key];
        } 
        // Otherwise keep going
        return res[key];
      },
      obj
    );
    return pulled;
};

/* --------------------- test logs --------------------- */

const testObj = {
  foo: {
    bar: [
      { baz: 'hello' }
    ]
  }
};

console.log('--------- TEST TOPATH --------');
console.log('undefined ---->', toPath());
console.log('foo ---->', toPath('foo'));
console.log('foo.bar[0] ---->', toPath('foo.bar[0]'));
console.log('foo.bar[0].baz ---->', toPath('foo.bar[0].baz'));
console.log('foo.bar[3].baz ---->', toPath('foo.bar[3].baz'));
console.log('foo.bar.baz[0].taz.bar[10][3].bar.0.5 ---->', toPath('foo.bar.baz[0].taz.bar[10][3].bar.0.5'));
console.log("foo['bar'].baz[0].taz.bar[10][3].bar['0'].5 ----> ", toPath("foo['bar'].baz[0].taz.bar[10][3].bar['0'].5"));
console.log('\n');

console.log('-------- TEST VALUES --------');
console.log(JSON.stringify(testObj), '---->', values(testObj));
console.log(JSON.stringify({}), '---->', values({}));
console.log(JSON.stringify({ foo: 1, bar: 'baz' }), '---->', values({ foo: 1, bar: 'baz' }));
console.log(JSON.stringify(), '---->', values());
console.log('\n');

console.log('---------- TEST HAS ----------');
console.log(JSON.stringify(testObj));
console.log('foo ---->', has(testObj, 'foo'));
console.log('foo.bar[0] ---->', has(testObj, 'foo.bar[0]'));
console.log('foo.bar[0].baz ---->', has(testObj, 'foo.bar[0].baz'));
console.log('foo.bar[3].baz ---->', has(testObj, 'foo.bar[3].baz'));
console.log('\n');

console.log('---------- TEST GET ----------');;
console.log(JSON.stringify(testObj));
console.log('undefined ---->', get(testObj));
console.log('foo ---->', get(testObj, 'foo'));
console.log('foo.bar[0] ---->', get(testObj, 'foo.bar[0]'));
console.log('foo.bar[0].baz ---->', get(testObj, 'foo.bar[0].baz'));
console.log('foo.bar[3].baz ---->', get(testObj, 'foo.bar[3].baz'));
console.log('\n');

console.log('---------- TEST SET ----------');
let testSetObj = {};
console.log(JSON.stringify(testSetObj));
console.log('foo ----> {}', set(testSetObj, 'foo', {}));
console.log(JSON.stringify(testSetObj));
console.log('foo.bar[0] ----> { baz: "hello" }', set(testSetObj, 'foo.bar[0]', { baz: 'hello' }));
console.log(JSON.stringify(testSetObj));
console.log('\n');

testSetObj = {};
console.log('foo.bar[0].baz ----> "hello"', set(testSetObj, 'foo.bar[0].baz', 'hello'));
console.log(JSON.stringify(testSetObj));
console.log('foo.bar[3].baz ----> "world"', set(testSetObj, 'foo.bar[3].baz', 'world'));
console.log(JSON.stringify(testSetObj));
console.log('foo.bar[3].baz ----> "change"', set(testSetObj, 'foo.bar[3].baz', 'change'));
console.log(JSON.stringify(testSetObj));
console.log('foo.laz ----> "world"', set(testSetObj, 'foo.laz', 'world'));
console.log(JSON.stringify(testSetObj));
console.log('\n');

testSetObj = {};
console.log('foo ----> "hello"', set(testSetObj, 'foo', 'hello'));
console.log(JSON.stringify(testSetObj));
console.log('\n');

testSetObj = {};
console.log('foo.bar.baz[0].taz.bar[10][3].bar.0.5 ----> 3', set(testSetObj, 'foo.bar.baz[0].taz.bar[10][3].bar.0.5', 3));
console.log(JSON.stringify(testSetObj));
console.log('\n');


console.log('---------- TEST UNSET ----------');
let testUnsetObj = {};
console.log(JSON.stringify(testUnsetObj));
console.log('foo ---->', unset(testUnsetObj, 'foo'));
console.log(JSON.stringify(testUnsetObj));
console.log('foo.bar[0] ---->', unset(testUnsetObj, 'foo.bar[0]'));
console.log(JSON.stringify(testUnsetObj));
console.log('\n');

testUnsetObj = { foo: { bar: [{ baz: 'hello' }, { raz: 'world'}] } };
console.log(JSON.stringify(testUnsetObj));
console.log('foo.bar[0] ---->', unset(testUnsetObj, 'foo.bar[0]'));
console.log(JSON.stringify(testUnsetObj));
console.log('foo.bar[1].raz ---->', unset(testUnsetObj, 'foo.bar[1].raz'));
console.log(JSON.stringify(testUnsetObj));
console.log('foo ---->', unset(testUnsetObj, 'foo'));
console.log(JSON.stringify(testUnsetObj));


console.log('---------- TEST PULLAT ----------');
testUnsetObj = {};
console.log(JSON.stringify(testUnsetObj));
console.log('foo ---->', pullAt(testUnsetObj, 'foo'));
console.log(JSON.stringify(testUnsetObj));
console.log('\n');

console.log('foo.bar[0] ---->', pullAt(testUnsetObj, 'foo.bar[0]'));
console.log(JSON.stringify(testUnsetObj));
console.log('\n');

testUnsetObj = { foo: { bar: [{ baz: 'hello' }, { raz: 'world'}] } };
console.log(JSON.stringify(testUnsetObj));
console.log('foo.bar[0] ---->', pullAt(testUnsetObj, 'foo.bar[0]'));
console.log(JSON.stringify(testUnsetObj));
console.log('\n');

console.log('foo.bar[1].raz ---->', pullAt(testUnsetObj, 'foo.bar[1].raz'));
console.log(JSON.stringify(testUnsetObj));
console.log('foo ---->', pullAt(testUnsetObj, 'foo'));
console.log(JSON.stringify(testUnsetObj));
console.log('\n');