Reducint node.parent.nodes!

lib/at-rule.d.ts

@@ -1,4 +1,7 @@
-import Container, { ContainerProps } from './container.js'
+import Container, {
+  ContainerProps,
+  ContainerWithChildren
+} from './container.js'
 
 declare namespace AtRule {
   export interface AtRuleRaws extends Record<string, unknown> {
@@ -116,7 +119,7 @@ declare class AtRule_ extends Container {
    * ```
    */
   params: string
-  parent: Container | undefined
+  parent: ContainerWithChildren | undefined
 
   raws: AtRule.AtRuleRaws
 

lib/container.d.ts

@@ -5,6 +5,12 @@ import Node, { ChildNode, ChildProps, NodeProps } from './node.js'
 import Rule from './rule.js'
 
 declare namespace Container {
+  export class ContainerWithChildren<
+    Child extends Node = ChildNode
+  > extends Container_<Child> {
+    nodes: Child[]
+  }
+
   export interface ValueOptions {
     /**
      * String that’s used to narrow down values and speed up the regexp search.
@@ -66,7 +72,15 @@ declare abstract class Container_<Child extends Node = ChildNode> extends Node {
    * @return This node for methods chain.
    */
   append(
-    ...nodes: (ChildProps | ChildProps[] | Node | Node[] | string | string[])[]
+    ...nodes: (
+      | ChildProps
+      | ChildProps[]
+      | Node
+      | Node[]
+      | string
+      | string[]
+      | undefined
+    )[]
   ): this
 
   assign(overrides: Container.ContainerProps | object): this
@@ -146,7 +160,14 @@ declare abstract class Container_<Child extends Node = ChildNode> extends Node {
    */
   insertAfter(
     oldNode: Child | number,
-    newNode: Child | Child[] | ChildProps | ChildProps[] | string | string[]
+    newNode:
+      | Child
+      | Child[]
+      | ChildProps
+      | ChildProps[]
+      | string
+      | string[]
+      | undefined
   ): this
   /**
    * Insert new node before old node within the container.
@@ -161,7 +182,14 @@ declare abstract class Container_<Child extends Node = ChildNode> extends Node {
    */
   insertBefore(
     oldNode: Child | number,
-    newNode: Child | Child[] | ChildProps | ChildProps[] | string | string[]
+    newNode:
+      | Child
+      | Child[]
+      | ChildProps
+      | ChildProps[]
+      | string
+      | string[]
+      | undefined
   ): this
 
   /**
@@ -202,7 +230,15 @@ declare abstract class Container_<Child extends Node = ChildNode> extends Node {
    * @return This node for methods chain.
    */
   prepend(
-    ...nodes: (ChildProps | ChildProps[] | Node | Node[] | string | string[])[]
+    ...nodes: (
+      | ChildProps
+      | ChildProps[]
+      | Node
+      | Node[]
+      | string
+      | string[]
+      | undefined
+    )[]
   ): this
   /**
    * Add child to the end of the node.
@@ -447,6 +483,8 @@ declare abstract class Container_<Child extends Node = ChildNode> extends Node {
   get last(): Child | undefined
 }
 
-declare class Container<Child extends Node = ChildNode> extends Container_<Child> {}
+declare class Container<
+  Child extends Node = ChildNode
+> extends Container_<Child> {}
 
 export = Container

lib/container.js

@@ -173,6 +173,8 @@ class Container extends Node {
   normalize(nodes, sample) {
     if (typeof nodes === 'string') {
       nodes = cleanSource(parse(nodes).nodes)
+    } else if (typeof nodes === 'undefined') {
+      nodes = []
     } else if (Array.isArray(nodes)) {
       nodes = nodes.slice(0)
       for (let i of nodes) {

lib/declaration.d.ts

@@ -1,4 +1,4 @@
-import Container from './container.js'
+import { ContainerWithChildren } from './container.js'
 import Node from './node.js'
 
 declare namespace Declaration {
@@ -79,7 +79,7 @@ declare class Declaration_ extends Node {
    */
   important: boolean
 
-  parent: Container | undefined
+  parent: ContainerWithChildren | undefined
 
   /**
    * The property name for a CSS declaration.

lib/node.d.ts

@@ -246,7 +246,7 @@ declare abstract class Node_ {
    * @param newNode New node.
    * @return This node for methods chain.
    */
-  after(newNode: Node | Node.ChildProps | Node[] | string): this
+  after(newNode: Node | Node.ChildProps | Node[] | string | undefined): this
 
   /**
    * It assigns properties to an existing node instance.
@@ -273,7 +273,7 @@ declare abstract class Node_ {
    * @param newNode New node.
    * @return This node for methods chain.
    */
-  before(newNode: Node | Node.ChildProps | Node[] | string): this
+  before(newNode: Node | Node.ChildProps | Node[] | string | undefined): this
 
   /**
    * Clear the code style properties for the node and its children.
@@ -531,6 +531,6 @@ declare abstract class Node_ {
   warn(result: Result, message: string, options?: WarningOptions): Warning
 }
 
-declare class Node extends Node_ { }
+declare class Node extends Node_ {}
 
 export = Node

lib/rule.d.ts

@@ -1,4 +1,7 @@
-import Container, { ContainerProps } from './container.js'
+import Container, {
+  ContainerProps,
+  ContainerWithChildren
+} from './container.js'
 
 declare namespace Rule {
   export interface RuleRaws extends Record<string, unknown> {
@@ -70,7 +73,7 @@ declare namespace Rule {
  */
 declare class Rule_ extends Container {
   nodes: NonNullable<Container['nodes']>
-  parent: Container | undefined
+  parent: ContainerWithChildren | undefined
   raws: Rule.RuleRaws
   /**
    * The rule’s full selector represented as a string.

test/container.test.ts

@@ -638,18 +638,18 @@ test('insertBefore() receives array', () => {
 
 test('insertBefore() receives pre-existing child node - a', () => {
   let a = parse('a{ align-items: start; color: red; z-index: 1 }')
-  let declA = (a.first as Rule).nodes[0];
-  let declC = (a.first as Rule).nodes[2];
-  declC.before(declA);
+  let declA = (a.first as Rule).nodes[0]
+  let declC = (a.first as Rule).nodes[2]
+  declC.before(declA)
 
   is(a.toString(), 'a{ color: red; align-items: start; z-index: 1 }')
 })
 
 test('insertBefore() receives pre-existing child node - b', () => {
   let a = parse('a{ align-items: start; color: red; z-index: 1 }')
-  let declA = (a.first as Rule).nodes[0];
-  let declC = (a.first as Rule).nodes[2];
-  declA.before(declC);
+  let declA = (a.first as Rule).nodes[0]
+  let declC = (a.first as Rule).nodes[2]
+  declA.before(declC)
 
   is(a.toString(), 'a{ z-index: 1; align-items: start; color: red }')
 })
@@ -708,18 +708,18 @@ test('insertAfter() receives array', () => {
 
 test('insertAfter() receives pre-existing child node - a', () => {
   let a = parse('a{ align-items: start; color: red; z-index: 1 }')
-  let declA = (a.first as Rule).nodes[0];
-  let declC = (a.first as Rule).nodes[2];
-  declC.after(declA);
+  let declA = (a.first as Rule).nodes[0]
+  let declC = (a.first as Rule).nodes[2]
+  declC.after(declA)
 
   is(a.toString(), 'a{ color: red; z-index: 1; align-items: start }')
 })
 
 test('insertAfter() receives pre-existing child node - b', () => {
   let a = parse('a{ align-items: start; color: red; z-index: 1 }')
-  let declA = (a.first as Rule).nodes[0];
-  let declC = (a.first as Rule).nodes[2];
-  declA.after(declC);
+  let declA = (a.first as Rule).nodes[0]
+  let declC = (a.first as Rule).nodes[2]
+  declA.after(declC)
 
   is(a.toString(), 'a{ align-items: start; z-index: 1; color: red }')
 })
@@ -874,7 +874,7 @@ test('allows to clone nodes', () => {
 
 test('container.nodes can be sorted', () => {
   let root = parse('@b; @c; @a;')
-  let b = root.nodes[0];
+  let b = root.nodes[0]
 
   root.nodes.sort((x, y) => {
     return (x as AtRule).name.localeCompare((y as AtRule).name)
@@ -884,19 +884,30 @@ test('container.nodes can be sorted', () => {
   is(root.toString(), ' @a;@b; @c;')
 
   // Sorted nodes are reflected in "walk".
-  let result: string[] = [];
-  root.walkAtRules((atRule) => {
+  let result: string[] = []
+  root.walkAtRules(atRule => {
     result.push(atRule.name.trim())
-  });
+  })
 
   is(result.join(' '), 'a b c')
 
   // Sorted nodes have the corect "index".
   is(root.index(b), 1)
 
   // Inserting after a sorted node results in the correct order.
-  b.after('@d;');
+  b.after('@d;')
   is(root.toString(), ' @a;@b;@d; @c;')
 })
 
+test('ignores undefined on adding', () => {
+  let rule = parse('a { a: 1; b: 2 }').first as Rule
+  rule.append({ prop: 'c', value: '3' }, undefined)
+  rule.prepend(undefined)
+  rule.insertAfter(0, undefined)
+  rule.insertBefore(0, undefined)
+  rule.after(undefined)
+  rule.before(undefined)
+  is(rule.parent!.toString(), 'a { a: 1; b: 2; c: 3 }')
+})
+
 test.run()

test/types.ts

@@ -4,7 +4,7 @@ const plugin: PluginCreator<string> = prop => {
   return {
     Declaration: (decl, { Comment, result }) => {
       if (decl.prop === prop) {
-        decl.warn(result, `${decl.prop} found`)
+        decl.warn(result, `${decl.prop} found in ${decl.parent?.nodes.length}`)
         decl.replaceWith(new Comment({ text: `${decl.prop} removed` }))
       }
     },