text-treeview

node.js library to write a tree hierarchy for console output. 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. ``` npm install text-treeview ``` ``` 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 LEAFNODE (├─ ) 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`;

} ``` - 2021-11-03 - Changed test library and cleaned up references