README.md
# text-treeview
node.js library to write a tree hierarchy for console output.
[](https://travis-ci.org/dlid/text-treeview) [](https://codecov.io/gh/dlid/text-treeview) [](https://codeclimate.com/github/dlid/text-treeview/maintainability)
# The why
When writing another library I was working with a deep hierarchy of objects that I had to verify.
I iterated the objects and wrote some metadata using `space` for indenting the lines. But as the hierarchy became more complex it was difficult to follow.
So I wrote a little helper function that could take an array of objects and create a treeview-like experience, making it a lot easer to see the actual structure.
Then I decided it was an excellent little function to share with everyone.
# Installation
```
npm install text-treeview
```
# Basic usage
```
var tree = require('text-treeview');
console.log(tree([
{
text : "Girls",
children : [
"Anna",
"Lisa",
"Bea"
]
},
{
text : "Boys",
children : [
"Kalle",
"Åre",
"Asgar"
]
}
]));
```
Will give you the result:
```
├─ Girls
│ ├─ Anna
│ ├─ Lisa
│ └─ Bea
└─ Boys
├─ Kalle
├─ Åre
└─ Asgar
```
## Tree array
Each item in the array must be either a string, or an object with a `text` property. You can also use the optional `children` property for an object to add child nodes to the item.
The following snippets will yield identical results:
```
console.log(tree([
"Hello",
"Hej",
"Hohejoj"
]));
console.log(tree([
{ text : "Hello" },
{ text : "Hej" },
{ text : "Hohejoj" }
]));
```
## Children
Each child item follow the same pattern. A string or the object described above.
```
console.log(tree([
{
text : "Some items",
children : [
"Item 1",
"Item 2",
{
text : "Item 3",
children : [ "Item 3.1", "Item 3.2"]
}
]
}
]));
```
will give the result
```
└─ Some items
├─ Item 1
├─ Item 2
└─ Item 3
├─ Item 3.1
└─ Item 3.2
```
## Options
You pass the options object as the second parameter. These are only a few options and these are the the default ones.
```
{
showRootLines : true,
format : (indents, treeNode, node) => {
return `${indents.join('')}${treeNode}${node.text}\n`;
}
}
```
- Set `showRootLines` to false to remove the lines on the root level
- Use `format` to customize each node. See details below.
### format function
`format (indents, treeNode, node, parentNode)`
The format function will create each node and will take four parameters
- `indents` is an array of each treeview "indent" that will build the treeview.
- This array contains all the node indicators further up the tree that other levels and nodes in the tree has created.
- These are either a NODE `│ ` or EMPTY SPACE ` `. These should be joined toghether and put in front of the string.
- `treeNode` is the actual node indicator for the current node (this is are either a LEAF_NODE (`├─ `) or END NODE (`└─ `).
- `node` is the node object
- `parentNode` is the parent node of the current node
The default function simply looks exactly like this:
```
function format(indents, treeNode, node) {
return `${indents.join('')}${treeNode}${node.text}\n`;
}
```
# Change log
- `2021-11-03` - Changed test library and cleaned up references