feat(eslint-plugin): [member-ordering] add index signature

packages/eslint-plugin/docs/rules/member-ordering.md

@@ -17,8 +17,8 @@ It allows to group members by their type (e.g. `public-static-field`, `protected
   classes?: Array<MemberType> | never
   classExpressions?: Array<MemberType> | never
 
-  interfaces?: ['field' | 'method' | 'constructor'] | never
-  typeLiterals?: ['field' | 'method' | 'constructor'] | never
+  interfaces?: ['signature' | 'field' | 'method' | 'constructor'] | never
+  typeLiterals?: ['signature' | 'field' | 'method' | 'constructor'] | never
 }
 ```
 
@@ -30,6 +30,9 @@ There are multiple ways to specify the member types. The most explicit and granu
 
 ```json5
 [
+  // Index signature
+  'signature',
+
   // Fields
   'public-static-field',
   'protected-static-field',
@@ -67,6 +70,9 @@ It is also possible to group member types by their accessibility (`static`, `ins
 
 ```json5
 [
+  // Index signature
+  // No accessibility for index signature. See above.
+
   // Fields
   'public-field', // = ['public-static-field', 'public-instance-field'])
   'protected-field', // = ['protected-static-field', 'protected-instance-field'])
@@ -88,6 +94,9 @@ Another option is to group the member types by their scope (`public`, `protected
 
 ```json5
 [
+  // Index signature
+  // No scope for index signature. See above.
+
   // Fields
   'static-field', // = ['public-static-field', 'protected-static-field', 'private-static-field'])
   'instance-field', // = ['public-instance-field', 'protected-instance-field', 'private-instance-field'])
@@ -109,6 +118,9 @@ The third grouping option is to ignore both scope and accessibility.
 
 ```json5
 [
+  // Index signature
+  // No grouping for index signature. See above.
+
   // Fields
   'field', // = ['public-static-field', 'protected-static-field', 'private-static-field', 'public-instance-field', 'protected-instance-field', 'private-instance-field',
   //              'public-abstract-field', 'protected-abstract-field', private-abstract-field'])
@@ -129,6 +141,8 @@ The default configuration looks as follows:
 ```json
 {
   "default": [
+    "signature",
+
     "public-static-field",
     "protected-static-field",
     "private-static-field",
@@ -186,7 +200,7 @@ Note: The default configuration contains member group types which contain other
 
 Note: The `default` options are overwritten in these examples.
 
-#### Configuration: `{ "default": ["method", "constructor", "field"] }`
+#### Configuration: `{ "default": ["signature", "method", "constructor", "field"] }`
 
 ##### Incorrect examples
 
@@ -197,6 +211,8 @@ interface Foo {
   new (); // -> constructor
 
   A(): void; // -> method
+
+  [Z: string]: any; // -> signature
 }
 ```
 
@@ -209,6 +225,8 @@ type Foo = {
   // no constructor
 
   A(): void; // -> method
+
+  // no signature
 };
 ```
 
@@ -224,10 +242,12 @@ class Foo {
 
   public static A(): void {} // -> method
   public B(): void {} // -> method
+
+  [Z: string]: any; // -> signature
 }
 ```
 
-Note: Accessibility or scope are ignored with this ignored.
+Note: Accessibility or scope are ignored with this configuration.
 
 ```ts
 const Foo = class {
@@ -239,6 +259,8 @@ const Foo = class {
   public static A(): void {} // -> method
   public B(): void {} // -> method
 
+  [Z: string]: any; // -> signature
+
   protected static E: string; // -> field
 };
 ```
@@ -249,6 +271,8 @@ Note: Not all members have to be grouped to find rule violations.
 
 ```ts
 interface Foo {
+  [Z: string]: any; // -> signature
+
   A(): void; // -> method
 
   new (); // -> constructor
@@ -259,6 +283,8 @@ interface Foo {
 
 ```ts
 type Foo = {
+  // no signature
+
   A(): void; // -> method
 
   // no constructor
@@ -269,6 +295,8 @@ type Foo = {
 
 ```ts
 class Foo {
+  [Z: string]: any; // -> signature
+
   public static A(): void {} // -> method
   public B(): void {} // -> method
 
@@ -282,6 +310,8 @@ class Foo {
 
 ```ts
 const Foo = class {
+  [Z: string]: any; // -> signature
+
   public static A(): void {} // -> method
   public B(): void {} // -> method
 
@@ -311,6 +341,8 @@ class Foo {
 
   public static A(): void {} // (irrelevant)
 
+  [Z: string]: any; // (irrelevant)
+
   public B(): void {} // -> public instance method
 }
 ```
@@ -321,6 +353,8 @@ Note: Public instance methods should come first before public static fields. Eve
 const Foo = class {
   private C: string; // (irrelevant)
 
+  [Z: string]: any; // (irrelevant)
+
   public static E: string; // -> public static field
 
   public D: string; // (irrelevant)
@@ -350,6 +384,8 @@ class Foo {
   constructor() {} // (irrelevant)
 
   public static A(): void {} // (irrelevant)
+
+  [Z: string]: any; // (irrelevant)
 }
 ```
 
@@ -359,6 +395,8 @@ const Foo = class {
 
   private C: string; // (irrelevant)
 
+  [Z: string]: any; // (irrelevant)
+
   public D: string; // (irrelevant)
 
   constructor() {} // (irrelevant)
@@ -384,6 +422,8 @@ class Foo {
   private static D: string; // -> static field
 
   public static A: string; // -> public static field
+
+  [Z: string]: any; // (irrelevant)
 }
 ```
 
@@ -402,6 +442,8 @@ const foo = class {
   protected static C: string; // -> static field
   private static D: string; // -> static field
 
+  [Z: string]: any; // (irrelevant)
+
   public static A: string; // -> public static field
 };
 ```
@@ -424,6 +466,8 @@ class Foo {
 
 ```ts
 const foo = class {
+  [Z: string]: any; // -> signature
+
   public static A: string; // -> public static field
 
   constructor() {} // -> constructor
@@ -596,11 +640,11 @@ const foo = class {
 
 Note: If this is not set, the `default` will automatically be applied to classes expressions as well. If a `interfaces` configuration is provided, only this configuration will be used for `interfaces` (i.e. nothing will be merged with `default`).
 
-Note: The configuration for `interfaces` only allows a limited set of member types: `field`, `constructor` and `method`.
+Note: The configuration for `interfaces` only allows a limited set of member types: `signature`, `field`, `constructor` and `method`.
 
 Note: The configuration for `interfaces` does not apply to type literals (use `typeLiterals` for them).
 
-#### Configuration: `{ "interfaces": ["method", "constructor", "field"] }`
+#### Configuration: `{ "interfaces": ["signature", "method", "constructor", "field"] }`
 
 ##### Incorrect example
 
@@ -611,13 +655,17 @@ interface Foo {
   new (); // -> constructor
 
   A(): void; // -> method
+
+  [Z: string]: any; // -> signature
 }
 ```
 
 ##### Correct example
 
 ```ts
 interface Foo {
+  [Z: string]: any; // -> signature
+
   A(): void; // -> method
 
   new (); // -> constructor
@@ -630,11 +678,11 @@ interface Foo {
 
 Note: If this is not set, the `default` will automatically be applied to classes expressions as well. If a `typeLiterals` configuration is provided, only this configuration will be used for `typeLiterals` (i.e. nothing will be merged with `default`).
 
-Note: The configuration for `typeLiterals` only allows a limited set of member types: `field`, `constructor` and `method`.
+Note: The configuration for `typeLiterals` only allows a limited set of member types: `signature`, `field`, `constructor` and `method`.
 
-Note: The configuration for `typeLiterals` does not apply to type literals (use `interfaces` for them).
+Note: The configuration for `typeLiterals` does not apply to interfaces (use `interfaces` for them).
 
-#### Configuration: `{ "typeLiterals": ["method", "constructor", "field"] }`
+#### Configuration: `{ "typeLiterals": ["signature", "method", "constructor", "field"] }`
 
 ##### Incorrect example
 
@@ -645,13 +693,17 @@ type Foo = {
   A(): void; // -> method
 
   new (); // -> constructor
+
+  [Z: string]: any; // -> signature
 };
 ```
 
 ##### Correct example
 
 ```ts
 type Foo = {
+  [Z: string]: any; // -> signature
+
   A(): void; // -> method
 
   new (); // -> constructor

packages/eslint-plugin/src/rules/member-ordering.ts

@@ -39,6 +39,7 @@ const allMemberTypes = ['field', 'method', 'constructor'].reduce<string[]>(
   },
   [],
 );
+allMemberTypes.unshift('signature');
 
 export default util.createRule<Options, MessageIds>({
   name: 'member-ordering',
@@ -104,7 +105,7 @@ export default util.createRule<Options, MessageIds>({
               {
                 type: 'array',
                 items: {
-                  enum: ['field', 'method', 'constructor'],
+                  enum: ['signature', 'field', 'method', 'constructor'],
                 },
               },
             ],
@@ -117,7 +118,7 @@ export default util.createRule<Options, MessageIds>({
               {
                 type: 'array',
                 items: {
-                  enum: ['field', 'method', 'constructor'],
+                  enum: ['signature', 'field', 'method', 'constructor'],
                 },
               },
             ],
@@ -130,6 +131,8 @@ export default util.createRule<Options, MessageIds>({
   defaultOptions: [
     {
       default: [
+        'signature',
+
         'public-static-field',
         'protected-static-field',
         'private-static-field',
@@ -194,7 +197,6 @@ export default util.createRule<Options, MessageIds>({
       node: TSESTree.ClassElement | TSESTree.TypeElement,
     ): string | null {
       // TODO: add missing TSCallSignatureDeclaration
-      // TODO: add missing TSIndexSignature
       switch (node.type) {
         case AST_NODE_TYPES.TSAbstractMethodDefinition:
         case AST_NODE_TYPES.MethodDefinition:
@@ -210,6 +212,8 @@ export default util.createRule<Options, MessageIds>({
             : 'field';
         case AST_NODE_TYPES.TSPropertySignature:
           return 'field';
+        case AST_NODE_TYPES.TSIndexSignature:
+          return 'signature';
         default:
           return null;
       }
@@ -235,6 +239,8 @@ export default util.createRule<Options, MessageIds>({
             : util.getNameFromClassMember(node, sourceCode);
         case AST_NODE_TYPES.TSConstructSignatureDeclaration:
           return 'new';
+        case AST_NODE_TYPES.TSIndexSignature:
+          return util.getNameFromIndexSignature(node);
         default:
           return null;
       }

packages/eslint-plugin/src/util/misc.ts

@@ -48,6 +48,19 @@ export type InferMessageIdsTypeFromRule<T> = T extends TSESLint.RuleModule<
   ? TMessageIds
   : unknown;
 
+/**
+ * Gets a string representation of the name of the index signature.
+ */
+export function getNameFromIndexSignature(
+  node: TSESTree.TSIndexSignature,
+): string {
+  const propName: TSESTree.PropertyName | undefined = node.parameters.find(
+    (parameter: TSESTree.Parameter): parameter is TSESTree.Identifier =>
+      parameter.type === AST_NODE_TYPES.Identifier,
+  );
+  return propName ? getNameFromPropertyName(propName) : '(index signature)';
+}
+
 /**
  * Gets a string name representation of the given PropertyName node
  */