Если я правильно понимаю ваш вопрос, то, возможно, вы могли бы изменить свою функцию поиска пути следующим образом, чтобы достичь того, что вам нужно:
const buildFullTree = (departmentTree, category, data = []) => {
const findPath = (node, category) => {
//If current node matches search node, return tail of path result
if (node.id === category.id) {
return [node]
} else {
//If current node not search node match, examine children. For first
//child that returns an array (path), prepend current node to that
//path result
for (const child of node.children) {
const childPath = findPath(child, category)
if (Array.isArray(childPath)) {
childPath.unshift(child)
return childPath
}
}
}
}
const foundPath = findPath(departmentTree, category)
// If search from root returns a path, prepend root node to path in
// data result
if (Array.isArray(foundPath)) {
data.push(departmentTree)
data.push(...foundPath)
}
return data
}
const departmentTree = {
id: 5,
title: 'department',
level: 1,
children: [{
id: 1,
parentId: 5,
title: 'category',
level: 2,
children: [{
id: 15,
parentId: 1,
title: 'subcategory',
level: 3,
children: []
}, {
id: 18,
parentId: 1,
level: 3,
title: 'subcategory',
children: []
}, {
id: 26,
parentId: 1,
level: 3,
title: 'subcategory',
children: [{
id: 75,
parentId: 26,
level: 4,
title: 'sub-subcategory',
children: []
}, {
id: 78,
parentId: 26,
level: 4,
title: 'sub-subcategory',
children: []
}]
}]
}, {
id: 23823,
title: 'category',
level: 2,
children: []
}, {
id: 9,
parentId: 5,
level: 2,
title: 'category',
children: [{
id: 48414,
parentId: 9,
level: 3,
title: 'subcategory',
children: []
}, {
id: 2414,
parentId: 9,
level: 3,
title: 'subcategory',
children: []
}, {
id: 42414,
parentId: 9,
level: 3,
title: 'subcategory',
children: [{
id: 2323213,
parentId: 42414,
level: 4,
title: 'sub-subcategory',
children: []
}, {
id: 322332,
parentId: 42414,
level: 4,
title: 'sub-subcategory',
children: []
}]
}]
}]
};
console.log('Path to 2323213:',
buildFullTree(departmentTree, {
id: 2323213
}).map(node => node.id).join(' -> '))
console.log('Path to 23823:',
buildFullTree(departmentTree, {
id: 23823
}).map(node => node.id).join(' -> '))
console.log('Path to -1 (non existing node):',
buildFullTree(departmentTree, {
id: -1
}).map(node => node.id).join(' -> '))