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Add consistent-class-member-order rule (#3226)
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‎docs/rules/consistent-class-member-order.md‎

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# consistent-class-member-order
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📝 Enforce consistent class member order.
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💼🚫 This rule is enabled in the ✅ `recommended` [config](https://github.com/sindresorhus/eslint-plugin-unicorn#recommended-config). This rule is _disabled_ in the ☑️ `unopinionated` [config](https://github.com/sindresorhus/eslint-plugin-unicorn#recommended-config).
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💡 This rule is manually fixable by [editor suggestions](https://eslint.org/docs/latest/use/core-concepts#rule-suggestions).
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<!-- end auto-generated rule header -->
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This rule enforces the following class member order:
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1. Static fields
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2. Static blocks
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3. Private instance fields
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4. Public instance fields
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5. Constructors
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6. Static methods
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7. Private instance methods
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8. Public instance methods
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Static members are grouped by `static` before privacy, so `static #foo` belongs with other static fields or methods.
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TypeScript `protected` members follow the same order as public members.
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This rule does not autofix because fields and static blocks run in declaration order, and method order is observable through property reflection.
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It may offer a manual suggestion for simple class bodies without comments, decorators, computed keys, or unsupported members.
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This rule is intentionally simple. It only enforces group order and will not add options for sorting within groups, newline handling, or more detailed member categories. Use a dedicated sorting rule if you need that.
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## Options
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Type: `object`
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### order
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Type: `string[]`
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Default:
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```js
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[
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'static-field',
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'static-block',
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'private-field',
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'public-field',
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'constructor',
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'static-method',
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'private-method',
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'public-method',
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]
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```
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The array must contain each group exactly once.
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## Examples
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```js
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// ❌
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class Foo {
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constructor() {}
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#privateField = 1;
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publicField = 1;
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}
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```
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```js
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// ✅
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class Foo {
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static staticField = 1;
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#privateField = 1;
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publicField = 1;
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constructor() {}
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}
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```
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```js
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// ❌
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class Foo {
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publicMethod() {}
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#privateMethod() {}
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}
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```
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```js
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// ✅
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class Foo {
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static staticMethod() {}
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#privateMethod() {}
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publicMethod() {}
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}
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```

‎readme.md‎

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| [class-reference-in-static-methods](docs/rules/class-reference-in-static-methods.md) | Enforce consistent class references in static methods. | ✅ | | 💡 |
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| [comment-content](docs/rules/comment-content.md) | Enforce better comment content. | ✅ | 🔧 | |
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| [consistent-assert](docs/rules/consistent-assert.md) | Enforce consistent assertion style with `node:assert`. | ✅ | 🔧 | |
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| [consistent-class-member-order](docs/rules/consistent-class-member-order.md) | Enforce consistent class member order. | ✅ | | 💡 |
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| [consistent-compound-words](docs/rules/consistent-compound-words.md) | Enforce consistent spelling of compound words in identifiers. | ✅ ☑️ | | 💡 |
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| [consistent-date-clone](docs/rules/consistent-date-clone.md) | Prefer passing `Date` directly to the constructor when cloning. | ✅ ☑️ | 🔧 | |
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| [consistent-destructuring](docs/rules/consistent-destructuring.md) | Use destructured variables over properties. | | | 💡 |

‎rules/consistent-class-member-order.js‎

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const MESSAGE_ID = 'consistent-class-member-order';
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const MESSAGE_ID_SUGGESTION = 'consistent-class-member-order-suggestion';
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const messages = {
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[MESSAGE_ID]: 'Expected {{current}} to come before {{previous}}.',
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[MESSAGE_ID_SUGGESTION]: 'Reorder class members by group.',
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};
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const GROUP_STATIC_FIELD = 'static-field';
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const GROUP_STATIC_BLOCK = 'static-block';
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const GROUP_PRIVATE_FIELD = 'private-field';
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const GROUP_PUBLIC_FIELD = 'public-field';
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const GROUP_CONSTRUCTOR = 'constructor';
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const GROUP_STATIC_METHOD = 'static-method';
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const GROUP_PRIVATE_METHOD = 'private-method';
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const GROUP_PUBLIC_METHOD = 'public-method';
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const defaultOrder = [
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GROUP_STATIC_FIELD,
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GROUP_STATIC_BLOCK,
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GROUP_PRIVATE_FIELD,
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GROUP_PUBLIC_FIELD,
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GROUP_CONSTRUCTOR,
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GROUP_STATIC_METHOD,
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GROUP_PRIVATE_METHOD,
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GROUP_PUBLIC_METHOD,
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];
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const fieldTypes = new Set([
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'AccessorProperty',
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'PropertyDefinition',
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'TSAbstractAccessorProperty',
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'TSAbstractPropertyDefinition',
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]);
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const methodTypes = new Set([
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'MethodDefinition',
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'TSAbstractMethodDefinition',
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]);
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const isPrivateMember = member =>
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member.key?.type === 'PrivateIdentifier'
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|| member.accessibility === 'private';
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const getGroupLabel = group => group.replaceAll('-', ' ');
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const getMemberGroup = member => {
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if (member.type === 'StaticBlock') {
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return GROUP_STATIC_BLOCK;
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}
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if (
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methodTypes.has(member.type)
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&& member.kind === 'constructor'
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) {
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return GROUP_CONSTRUCTOR;
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}
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if (fieldTypes.has(member.type)) {
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if (member.static) {
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return GROUP_STATIC_FIELD;
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}
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return isPrivateMember(member)
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? GROUP_PRIVATE_FIELD
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: GROUP_PUBLIC_FIELD;
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}
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if (methodTypes.has(member.type)) {
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if (member.static) {
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return GROUP_STATIC_METHOD;
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}
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return isPrivateMember(member)
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? GROUP_PRIVATE_METHOD
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: GROUP_PUBLIC_METHOD;
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}
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};
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const getReorderedMembers = (classBody, order) => {
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const members = classBody.body.map((member, index) => ({
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member,
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index,
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group: getMemberGroup(member),
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}));
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if (
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members.some(({member, group}) =>
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group === undefined
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|| member.computed
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|| member.decorators?.length > 0)
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) {
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return;
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}
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return members.toSorted((first, second) =>
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order.get(first.group) - order.get(second.group)
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|| first.index - second.index);
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};
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const getMemberLineStart = (member, sourceCode) => {
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const {line} = sourceCode.getLoc(member).start;
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return sourceCode.getIndexFromLoc({line, column: 0});
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};
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const getMemberLineLeadingText = (member, sourceCode) => {
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const [memberStart] = sourceCode.getRange(member);
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const lineStart = getMemberLineStart(member, sourceCode);
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return sourceCode.text.slice(lineStart, memberStart);
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};
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const getMemberStart = (member, sourceCode) => {
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const [memberStart] = sourceCode.getRange(member);
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const lineStart = getMemberLineStart(member, sourceCode);
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const leadingText = getMemberLineLeadingText(member, sourceCode);
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return /^\s+$/v.test(leadingText)
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? lineStart
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: memberStart;
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};
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const isLineInitialMember = (member, sourceCode) =>
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/^\s*$/v.test(getMemberLineLeadingText(member, sourceCode));
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const getMemberText = (member, sourceCode) => {
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const [, end] = sourceCode.getRange(member);
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return sourceCode.text.slice(getMemberStart(member, sourceCode), end);
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};
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const getSuggestion = (classBody, order, sourceCode) => {
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if (
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classBody.body.length === 0
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|| sourceCode.getCommentsInside(classBody).length > 0
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|| classBody.body.some(member => !isLineInitialMember(member, sourceCode))
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) {
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return;
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}
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const reorderedMembers = getReorderedMembers(classBody, order);
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if (!reorderedMembers) {
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return;
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}
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const firstMember = classBody.body[0];
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const lastMember = classBody.body.at(-1);
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const start = getMemberStart(firstMember, sourceCode);
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const [, end] = sourceCode.getRange(lastMember);
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const replacement = reorderedMembers
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.map(({member}) => getMemberText(member, sourceCode))
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.join('\n\n');
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return [
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{
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messageId: MESSAGE_ID_SUGGESTION,
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fix: fixer => fixer.replaceTextRange([start, end], replacement),
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},
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];
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};
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/** @param {import('eslint').Rule.RuleContext} context */
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const create = context => {
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const {sourceCode} = context;
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const order = new Map(context.options[0].order.map((group, index) => [group, index]));
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context.on('ClassBody', function * (classBody) {
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const suggestion = getSuggestion(classBody, order, sourceCode);
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let shouldSuggest = suggestion !== undefined;
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let highestGroupIndex;
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let highestGroup;
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for (const member of classBody.body) {
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const group = getMemberGroup(member);
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if (group === undefined) {
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continue;
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}
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const groupIndex = order.get(group);
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if (
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highestGroupIndex !== undefined
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&& groupIndex < highestGroupIndex
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) {
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yield {
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node: member,
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messageId: MESSAGE_ID,
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data: {
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current: getGroupLabel(group),
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previous: getGroupLabel(highestGroup),
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},
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...(shouldSuggest && {suggest: suggestion}),
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};
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shouldSuggest = false;
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continue;
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}
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highestGroupIndex = groupIndex;
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highestGroup = group;
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}
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});
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};
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const schema = [
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{
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type: 'object',
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additionalProperties: false,
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properties: {
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order: {
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type: 'array',
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description: 'The class member group order.',
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items: {
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enum: defaultOrder,
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},
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minItems: defaultOrder.length,
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maxItems: defaultOrder.length,
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uniqueItems: true,
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},
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},
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},
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];
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/** @type {import('eslint').Rule.RuleModule} */
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const config = {
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create,
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meta: {
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type: 'suggestion',
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docs: {
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description: 'Enforce consistent class member order.',
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recommended: true,
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},
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hasSuggestions: true,
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schema,
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defaultOptions: [{order: defaultOrder}],
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messages,
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languages: [
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'js/js',
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],
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},
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};
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export default config;

‎rules/index.js‎

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export {default as 'class-reference-in-static-methods'} from './class-reference-in-static-methods.js';
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export {default as 'comment-content'} from './comment-content.js';
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export {default as 'consistent-assert'} from './consistent-assert.js';
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export {default as 'consistent-class-member-order'} from './consistent-class-member-order.js';
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export {default as 'consistent-compound-words'} from './consistent-compound-words.js';
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export {default as 'consistent-date-clone'} from './consistent-date-clone.js';
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export {default as 'consistent-destructuring'} from './consistent-destructuring.js';

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