Update plugins to support standalone components

- ThemedComponent wrappers should always import their base component. This ensures that it's always enough to only import the wrapper when we use it.
- This implies that all themeable components must be standalone

→ added rules to enforce this
→ updated usage rule to improve declaration/import handling

.eslintrc.json

@@ -245,6 +245,7 @@
         "rxjs/no-nested-subscribe": "off",     // todo: go over _all_ cases
 
         // Custom DSpace Angular rules
+        "dspace-angular-ts/themed-component-classes": "error",
         "dspace-angular-ts/themed-component-selectors": "error",
         "dspace-angular-ts/themed-component-usages": "error"
       }

lint/src/rules/ts/index.ts

@@ -10,12 +10,14 @@ import {
   RuleExports,
 } from '../../util/structure';
 /* eslint-disable import/no-namespace */
+import * as themedComponentClasses from './themed-component-classes';
 import * as themedComponentSelectors from './themed-component-selectors';
 import * as themedComponentUsages from './themed-component-usages';
 
 const index = [
-  themedComponentUsages,
+  themedComponentClasses,
   themedComponentSelectors,
+  themedComponentUsages,
 ] as unknown as RuleExports[];
 
 export = {

lint/src/rules/ts/themed-component-classes.ts

@@ -0,0 +1,378 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+import {
+  ESLintUtils,
+  TSESLint,
+  TSESTree,
+} from '@typescript-eslint/utils';
+
+import { fixture } from '../../../test/fixture';
+import {
+  getComponentImportNode,
+  getComponentInitializer,
+  getComponentStandaloneNode,
+} from '../../util/angular';
+import { appendObjectProperties } from '../../util/fix';
+import { DSpaceESLintRuleInfo } from '../../util/structure';
+import {
+  getBaseComponentClassName,
+  inThemedComponentOverrideFile,
+  isThemeableComponent,
+  isThemedComponentWrapper,
+} from '../../util/theme-support';
+import { getFilename } from '../../util/typescript';
+
+export enum Message {
+  NOT_STANDALONE = 'mustBeStandalone',
+  NOT_STANDALONE_IMPORTS_BASE = 'mustBeStandaloneAndImportBase',
+  WRAPPER_IMPORTS_BASE = 'wrapperShouldImportBase',
+}
+
+export const info = {
+  name: 'themed-component-classes',
+  meta: {
+    docs: {
+      description: `Formatting rules for themeable component classes`,
+    },
+    type: 'problem',
+    fixable: 'code',
+    schema: [],
+    messages: {
+      [Message.NOT_STANDALONE]: 'Themeable components must be standalone',
+      [Message.NOT_STANDALONE_IMPORTS_BASE]: 'Themeable component wrapper classes must be standalone and import the base class',
+      [Message.WRAPPER_IMPORTS_BASE]: 'Themed component wrapper classes must import the base class',
+    },
+  },
+  defaultOptions: [],
+} as DSpaceESLintRuleInfo;
+
+export const rule = ESLintUtils.RuleCreator.withoutDocs({
+  ...info,
+  create(context: TSESLint.RuleContext<Message, unknown[]>) {
+    const filename = getFilename(context);
+
+    if (filename.endsWith('.spec.ts')) {
+      return {};
+    }
+
+    function enforceStandalone(decoratorNode: TSESTree.Decorator, withBaseImport = false) {
+      const standaloneNode = getComponentStandaloneNode(decoratorNode);
+
+      if (standaloneNode === undefined) {
+        // We may need to add these properties in one go
+        if (!withBaseImport) {
+          context.report({
+            messageId: Message.NOT_STANDALONE,
+            node: decoratorNode,
+            fix(fixer) {
+              const initializer = getComponentInitializer(decoratorNode);
+              return appendObjectProperties(context, fixer, initializer, ['standalone: true']);
+            },
+          });
+        }
+      } else if (!standaloneNode.value) {
+        context.report({
+          messageId: Message.NOT_STANDALONE,
+          node: standaloneNode,
+          fix(fixer) {
+            return fixer.replaceText(standaloneNode, 'true');
+          },
+        });
+      }
+
+      if (withBaseImport) {
+        const baseClass = getBaseComponentClassName(decoratorNode);
+
+        if (baseClass === undefined) {
+          return;
+        }
+
+        const importsNode = getComponentImportNode(decoratorNode);
+
+        if (importsNode === undefined) {
+          if (standaloneNode === undefined) {
+            context.report({
+              messageId: Message.NOT_STANDALONE_IMPORTS_BASE,
+              node: decoratorNode,
+              fix(fixer) {
+                const initializer = getComponentInitializer(decoratorNode);
+                return appendObjectProperties(context, fixer, initializer, ['standalone: true', `imports: [${baseClass}]`]);
+              },
+            });
+          } else {
+            context.report({
+              messageId: Message.WRAPPER_IMPORTS_BASE,
+              node: decoratorNode,
+              fix(fixer) {
+                const initializer = getComponentInitializer(decoratorNode);
+                return appendObjectProperties(context, fixer, initializer, [`imports: [${baseClass}]`]);
+              },
+            });
+          }
+        } else {
+          // If we have an imports node, standalone: true will be enforced by another rule
+
+          const imports = importsNode.elements.map(e => (e as TSESTree.Identifier).name);
+
+          if (!imports.includes(baseClass) || imports.length > 1) {
+            // The wrapper should _only_ import the base component
+            context.report({
+              messageId: Message.WRAPPER_IMPORTS_BASE,
+              node: importsNode,
+              fix(fixer) {
+                // todo: this may leave unused imports, but that's better than mangling things
+                return fixer.replaceText(importsNode, `[${baseClass}]`);
+              },
+            });
+          }
+        }
+      }
+    }
+
+    return {
+      'ClassDeclaration > Decorator[expression.callee.name = "Component"]'(node: TSESTree.Decorator) {
+        const classNode = node.parent as TSESTree.ClassDeclaration;
+        const className = classNode.id?.name;
+
+        if (className === undefined) {
+          return;
+        }
+
+        if (isThemedComponentWrapper(node)) {
+          enforceStandalone(node, true);
+        } else if (inThemedComponentOverrideFile(filename)) {
+          enforceStandalone(node);
+        } else if (isThemeableComponent(className)) {
+          enforceStandalone(node);
+        }
+      },
+    };
+  },
+});
+
+export const tests = {
+  plugin: info.name,
+  valid: [
+    {
+      name: 'Regular non-themeable component',
+      code: `
+@Component({
+  selector: 'ds-something',
+  standalone: true,
+})
+class Something {
+}
+      `,
+    },
+    {
+      name: 'Base component',
+      code: `
+@Component({
+  selector: 'ds-base-test-themable',
+  standalone: true,
+})
+class TestThemeableTomponent {
+}
+      `,
+    },
+    {
+      name: 'Wrapper component',
+      filename: fixture('src/app/test/themed-test-themeable.component.ts'),
+      code: `
+@Component({
+  selector: 'ds-test-themable',
+  standalone: true,
+  imports: [
+    TestThemeableComponent,
+  ],
+})
+class ThemedTestThemeableTomponent extends ThemedComponent<TestThemeableComponent> {
+}
+      `,
+    },
+    {
+      name: 'Override component',
+      filename: fixture('src/themes/test/app/test/test-themeable.component.ts'),
+      code: `
+@Component({
+  selector: 'ds-themed-test-themable',
+  standalone: true,
+})
+class Override extends BaseComponent {
+}
+      `,
+    },
+  ],
+  invalid: [
+    {
+      name: 'Base component must be standalone',
+      code: `
+@Component({
+  selector: 'ds-base-test-themable',
+})
+class TestThemeableComponent {
+}
+      `,
+      errors:[
+        {
+          messageId: Message.NOT_STANDALONE,
+        },
+      ],
+      output: `
+@Component({
+  selector: 'ds-base-test-themable',
+  standalone: true,
+})
+class TestThemeableComponent {
+}
+      `,
+    },
+    {
+      name: 'Wrapper component must be standalone and import base component',
+      filename: fixture('src/app/test/themed-test-themeable.component.ts'),
+      code: `
+@Component({
+  selector: 'ds-test-themable',
+})
+class ThemedTestThemeableComponent extends ThemedComponent<TestThemeableComponent> {
+}
+      `,
+      errors:[
+        {
+          messageId: Message.NOT_STANDALONE_IMPORTS_BASE,
+        },
+      ],
+      output: `
+@Component({
+  selector: 'ds-test-themable',
+  standalone: true,
+  imports: [TestThemeableComponent],
+})
+class ThemedTestThemeableComponent extends ThemedComponent<TestThemeableComponent> {
+}
+      `,
+    },
+
+    {
+      name: 'Wrapper component must import base component (array present but empty)',
+      filename: fixture('src/app/test/themed-test-themeable.component.ts'),
+      code: `
+@Component({
+  selector: 'ds-test-themable',
+  standalone: true,
+  imports: [],
+})
+class ThemedTestThemeableComponent extends ThemedComponent<TestThemeableComponent> {
+}
+      `,
+      errors:[
+        {
+          messageId: Message.WRAPPER_IMPORTS_BASE,
+        },
+      ],
+      output: `
+@Component({
+  selector: 'ds-test-themable',
+  standalone: true,
+  imports: [TestThemeableComponent],
+})
+class ThemedTestThemeableComponent extends ThemedComponent<TestThemeableComponent> {
+}
+      `,
+    },
+    {
+      name: 'Wrapper component must import base component (array is wrong)',
+      filename: fixture('src/app/test/themed-test-themeable.component.ts'),
+      code: `
+import { SomethingElse } from './somewhere-else';
+
+@Component({
+  selector: 'ds-test-themable',
+  standalone: true,
+  imports: [
+    SomethingElse,
+  ],
+})
+class ThemedTestThemeableComponent extends ThemedComponent<TestThemeableComponent> {
+}
+      `,
+      errors:[
+        {
+          messageId: Message.WRAPPER_IMPORTS_BASE,
+        },
+      ],
+      output: `
+import { SomethingElse } from './somewhere-else';
+
+@Component({
+  selector: 'ds-test-themable',
+  standalone: true,
+  imports: [TestThemeableComponent],
+})
+class ThemedTestThemeableComponent extends ThemedComponent<TestThemeableComponent> {
+}
+      `,
+    },    {
+      name: 'Wrapper component must import base component (array is wrong)',
+      filename: fixture('src/app/test/themed-test-themeable.component.ts'),
+      code: `
+import { Something, SomethingElse } from './somewhere-else';
+
+@Component({
+  selector: 'ds-test-themable',
+  standalone: true,
+  imports: [
+    SomethingElse,
+  ],
+})
+class ThemedTestThemeableComponent extends ThemedComponent<TestThemeableComponent> {
+}
+      `,
+      errors:[
+        {
+          messageId: Message.WRAPPER_IMPORTS_BASE,
+        },
+      ],
+      output: `
+import { Something, SomethingElse } from './somewhere-else';
+
+@Component({
+  selector: 'ds-test-themable',
+  standalone: true,
+  imports: [TestThemeableComponent],
+})
+class ThemedTestThemeableComponent extends ThemedComponent<TestThemeableComponent> {
+}
+      `,
+    },
+    {
+      name: 'Override component must be standalone',
+      filename: fixture('src/themes/test/app/test/test-themeable.component.ts'),
+      code: `
+@Component({
+  selector: 'ds-themed-test-themable',
+})
+class Override extends BaseComponent {
+}
+      `,
+      errors:[
+        {
+          messageId: Message.NOT_STANDALONE,
+        },
+      ],
+      output: `
+@Component({
+  selector: 'ds-themed-test-themable',
+  standalone: true,
+})
+class Override extends BaseComponent {
+}
+      `,
+    },
+  ],
+};

lint/src/rules/ts/themed-component-usages.ts

@@ -12,6 +12,10 @@ import {
 } from '@typescript-eslint/utils';
 
 import { fixture } from '../../../test/fixture';
+import {
+  removeWithCommas,
+  replaceOrRemoveArrayIdentifier,
+} from '../../util/fix';
 import { DSpaceESLintRuleInfo } from '../../util/structure';
 import {
   allThemeableComponents,
@@ -22,14 +26,18 @@ import {
   isAllowedUnthemedUsage,
 } from '../../util/theme-support';
 import {
+  findImportSpecifier,
   findUsages,
+  findUsagesByName,
   getFilename,
+  relativePath,
 } from '../../util/typescript';
 
 export enum Message {
   WRONG_CLASS = 'mustUseThemedWrapperClass',
   WRONG_IMPORT = 'mustImportThemedWrapper',
   WRONG_SELECTOR = 'mustUseThemedWrapperSelector',
+  BASE_IN_MODULE = 'baseComponentNotNeededInModule',
 }
 
 export const info = {
@@ -53,6 +61,7 @@ There are a few exceptions where the base class can still be used:
       [Message.WRONG_CLASS]: 'Themeable components should be used via their ThemedComponent wrapper',
       [Message.WRONG_IMPORT]: 'Themeable components should be used via their ThemedComponent wrapper',
       [Message.WRONG_SELECTOR]: 'Themeable components should be used via their ThemedComponent wrapper',
+      [Message.BASE_IN_MODULE]: 'Base themeable components shouldn\'t be declared in modules',
     },
   },
   defaultOptions: [],
@@ -79,7 +88,11 @@ export const rule = ESLintUtils.RuleCreator.withoutDocs({
         messageId: Message.WRONG_CLASS,
         node: node,
         fix(fixer) {
+          if (node.parent.type === TSESTree.AST_NODE_TYPES.ArrayExpression) {
+            return replaceOrRemoveArrayIdentifier(context, fixer, node, entry.wrapperClass);
+          } else {
             return fixer.replaceText(node, entry.wrapperClass);
+          }
         },
       });
     }
@@ -118,18 +131,36 @@ export const rule = ESLintUtils.RuleCreator.withoutDocs({
         fix(fixer) {
           const ops = [];
 
-          const oldImportSource = declarationNode.source.value;
-          const newImportLine = `import { ${entry.wrapperClass} } from '${oldImportSource.replace(entry.baseFileName, entry.wrapperFileName)}';`;
+          const wrapperImport = findImportSpecifier(context, entry.wrapperClass);
+
+          if (findUsagesByName(context, entry.wrapperClass).length === 0) {
+            // Wrapper is not present in this file, safe to add import
+
+            const newImportLine = `import { ${entry.wrapperClass} } from '${relativePath(filename, entry.wrapperPath)}';`;
 
             if (declarationNode.specifiers.length === 1) {
               if (allUsages.length === badUsages.length) {
                 ops.push(fixer.replaceText(declarationNode, newImportLine));
-            } else {
-              ops.push(fixer.insertTextAfter(declarationNode, newImportLine));
+              } else if (wrapperImport === undefined) {
+                ops.push(fixer.insertTextAfter(declarationNode, '\n' + newImportLine));
               }
             } else {
-            ops.push(fixer.replaceText(specifierNode, entry.wrapperClass));
-            ops.push(fixer.insertTextAfter(declarationNode, newImportLine));
+              ops.push(...removeWithCommas(context, fixer, specifierNode));
+              if (wrapperImport === undefined) {
+                ops.push(fixer.insertTextAfter(declarationNode, '\n' + newImportLine));
+              }
+            }
+          } else {
+            // Wrapper already present in the file, remove import instead
+
+            if (allUsages.length === badUsages.length) {
+              if (declarationNode.specifiers.length === 1) {
+                // Make sure we remove the newline as well
+                ops.push(fixer.removeRange([declarationNode.range[0], declarationNode.range[1] + 1]));
+              } else {
+                ops.push(...removeWithCommas(context, fixer, specifierNode));
+              }
+            }
           }
 
           return ops;
@@ -147,9 +178,8 @@ export const rule = ESLintUtils.RuleCreator.withoutDocs({
         [`CallExpression[callee.object.name = "cy"][callee.property.name = "get"] > Literal:first-child[value = /.*${DISALLOWED_THEME_SELECTORS}.*/]`]: handleThemedSelectorQueriesInTests,
       };
     } else if (
-      filename.match(/(?!routing).module.ts$/)
+      filename.match(/(?!src\/themes\/).*(?!routing).module.ts$/)
       || filename.match(/themed-.+\.component\.ts$/)
-      || inThemedComponentFile(context)
     ) {
       // do nothing
       return {};
@@ -174,7 +204,7 @@ export const tests = {
     {
       name: 'allow wrapper class usages',
       code: `
-import { ThemedTestThemeableComponent } from '../test/themed-test-themeable.component.ts';
+import { ThemedTestThemeableComponent } from './app/test/themed-test-themeable.component';
 
 const config = {
   a: ThemedTestThemeableComponent,
@@ -192,7 +222,7 @@ export class TestThemeableComponent {
     {
       name: 'allow inheriting from base class',
       code: `
-import { TestThemeableComponent } from '../test/test-themeable.component.ts';
+import { TestThemeableComponent } from './app/test/test-themeable.component';
 
 export class ThemedAdminSidebarComponent extends ThemedComponent<TestThemeableComponent> {
 }
@@ -201,7 +231,7 @@ export class ThemedAdminSidebarComponent extends ThemedComponent<TestThemeableCo
     {
       name: 'allow base class in ViewChild',
       code: `
-import { TestThemeableComponent } from '../test/test-themeable.component.ts';
+import { TestThemeableComponent } from './app/test/test-themeable.component';
 
 export class Something {
   @ViewChild(TestThemeableComponent) test: TestThemeableComponent;
@@ -229,8 +259,8 @@ By.Css('#test > ds-themeable > #nest');
     {
       name: 'disallow direct usages of base class',
       code: `
-import { TestThemeableComponent } from '../test/test-themeable.component.ts';
-import { TestComponent } from '../test/test.component.ts';
+import { TestThemeableComponent } from './app/test/test-themeable.component';
+import { TestComponent } from './app/test/test.component';
 
 const config = {
   a: TestThemeableComponent,
@@ -246,8 +276,8 @@ const config = {
         },
       ],
       output: `
-import { ThemedTestThemeableComponent } from '../test/themed-test-themeable.component.ts';
-import { TestComponent } from '../test/test.component.ts';
+import { ThemedTestThemeableComponent } from './app/test/themed-test-themeable.component';
+import { TestComponent } from './app/test/test.component';
 
 const config = {
   a: ThemedTestThemeableComponent,
@@ -255,6 +285,61 @@ const config = {
 }
         `,
     },
+    {
+      name: 'disallow direct usages of base class, keep other imports',
+      code: `
+import { Something, TestThemeableComponent } from './app/test/test-themeable.component';
+import { TestComponent } from './app/test/test.component';
+
+const config = {
+  a: TestThemeableComponent,
+  b: TestComponent,
+  c: Something,
+}
+        `,
+      errors: [
+        {
+          messageId: Message.WRONG_IMPORT,
+        },
+        {
+          messageId: Message.WRONG_CLASS,
+        },
+      ],
+      output: `
+import { Something } from './app/test/test-themeable.component';
+import { ThemedTestThemeableComponent } from './app/test/themed-test-themeable.component';
+import { TestComponent } from './app/test/test.component';
+
+const config = {
+  a: ThemedTestThemeableComponent,
+  b: TestComponent,
+  c: Something,
+}
+        `,
+    },
+    {
+      name: 'handle array replacements correctly',
+      code: `
+const DECLARATIONS = [
+  Something,
+  TestThemeableComponent,
+  Something,
+  ThemedTestThemeableComponent,
+];
+        `,
+      errors: [
+        {
+          messageId: Message.WRONG_CLASS,
+        },
+      ],
+      output: `
+const DECLARATIONS = [
+  Something,
+  Something,
+  ThemedTestThemeableComponent,
+];
+        `,
+    },
     {
       name: 'disallow override selector in test queries',
       filename: fixture('src/app/test/test.component.spec.ts'),
@@ -337,30 +422,18 @@ cy.get('#test > ds-themeable > #nest');
     },
     {
       name: 'edge case: unable to find usage node through usage token, but import is still flagged and fixed',
+      filename: fixture('src/themes/test/app/test/other-themeable.component.ts'),
       code: `
 import { Component } from '@angular/core';
 
-import { Context } from '../../core/shared/context.model';
-import { TestThemeableComponent } from '../test/test-themeable.component.ts';
+import { Context } from './app/core/shared/context.model';
+import { TestThemeableComponent } from '../../../../app/test/test-themeable.component';
 
 @Component({
-  selector: 'ds-admin-search-page',
-  templateUrl: './admin-search-page.component.html',
-  styleUrls: ['./admin-search-page.component.scss'],
   standalone: true,
-  imports: [
-    TestThemeableComponent
-  ],
+  imports: [TestThemeableComponent],
 })
-
-/**
- * Component that represents a search page for administrators
- */
-export class AdminSearchPageComponent {
-  /**
-   * The context of this page
-   */
-  context: Context = Context.AdminSearch;
+export class UsageComponent {
 }
       `,
       errors: [
@@ -374,27 +447,53 @@ export class AdminSearchPageComponent {
       output: `
 import { Component } from '@angular/core';
 
-import { Context } from '../../core/shared/context.model';
-import { ThemedTestThemeableComponent } from '../test/themed-test-themeable.component.ts';
+import { Context } from './app/core/shared/context.model';
+import { ThemedTestThemeableComponent } from '../../../../app/test/themed-test-themeable.component';
 
 @Component({
-  selector: 'ds-admin-search-page',
-  templateUrl: './admin-search-page.component.html',
-  styleUrls: ['./admin-search-page.component.scss'],
   standalone: true,
-  imports: [
-    ThemedTestThemeableComponent
-  ],
+  imports: [ThemedTestThemeableComponent],
 })
+export class UsageComponent {
+}
+      `,
+    },
+    {
+      name: 'edge case edge case: both are imported, only wrapper is retained',
+      filename: fixture('src/themes/test/app/test/other-themeable.component.ts'),
+      code: `
+import { Component } from '@angular/core';
 
-/**
- * Component that represents a search page for administrators
- */
-export class AdminSearchPageComponent {
-  /**
-   * The context of this page
-   */
-  context: Context = Context.AdminSearch;
+import { Context } from './app/core/shared/context.model';
+import { TestThemeableComponent } from '../../../../app/test/test-themeable.component';
+import { ThemedTestThemeableComponent } from '../../../../app/test/themed-test-themeable.component';
+
+@Component({
+  standalone: true,
+  imports: [TestThemeableComponent, ThemedTestThemeableComponent],
+})
+export class UsageComponent {
+}
+      `,
+      errors: [
+        {
+          messageId: Message.WRONG_IMPORT,
+        },
+        {
+          messageId: Message.WRONG_CLASS,
+        },
+      ],
+      output: `
+import { Component } from '@angular/core';
+
+import { Context } from './app/core/shared/context.model';
+import { ThemedTestThemeableComponent } from '../../../../app/test/themed-test-themeable.component';
+
+@Component({
+  standalone: true,
+  imports: [ThemedTestThemeableComponent],
+})
+export class UsageComponent {
 }
       `,
     },

lint/src/util/angular.ts

@@ -10,8 +10,7 @@ import { TSESTree } from '@typescript-eslint/utils';
 import { getObjectPropertyNodeByName } from './typescript';
 
 export function getComponentSelectorNode(componentDecoratorNode: TSESTree.Decorator): TSESTree.StringLiteral | undefined {
-  const initializer = (componentDecoratorNode.expression as TSESTree.CallExpression).arguments[0] as TSESTree.ObjectExpression;
-  const property = getObjectPropertyNodeByName(initializer, 'selector');
+  const property = getComponentInitializerNodeByName(componentDecoratorNode, 'selector');
 
   if (property !== undefined) {
     // todo: support template literals as well
@@ -23,6 +22,62 @@ export function getComponentSelectorNode(componentDecoratorNode: TSESTree.Decora
   return undefined;
 }
 
+export function getComponentStandaloneNode(componentDecoratorNode: TSESTree.Decorator): TSESTree.BooleanLiteral | undefined {
+  const property = getComponentInitializerNodeByName(componentDecoratorNode, 'standalone');
+
+  if (property !== undefined) {
+    if (property.type === TSESTree.AST_NODE_TYPES.Literal && typeof property.value === 'boolean') {
+      return property as TSESTree.BooleanLiteral;
+    }
+  }
+
+  return undefined;
+}
+export function getComponentImportNode(componentDecoratorNode: TSESTree.Decorator): TSESTree.ArrayExpression | undefined {
+  const property = getComponentInitializerNodeByName(componentDecoratorNode, 'imports');
+
+  if (property !== undefined) {
+    if (property.type === TSESTree.AST_NODE_TYPES.ArrayExpression) {
+      return property as TSESTree.ArrayExpression;
+    }
+  }
+
+  return undefined;
+}
+
+export function getComponentClassName(decoratorNode: TSESTree.Decorator): string | undefined {
+  if (decoratorNode.parent.type !== TSESTree.AST_NODE_TYPES.ClassDeclaration) {
+    return undefined;
+  }
+
+  if (decoratorNode.parent.id?.type !== TSESTree.AST_NODE_TYPES.Identifier) {
+    return undefined;
+  }
+
+  return decoratorNode.parent.id.name;
+}
+
+export function getComponentSuperClassName(decoratorNode: TSESTree.Decorator): string | undefined {
+  if (decoratorNode.parent.type !== TSESTree.AST_NODE_TYPES.ClassDeclaration) {
+    return undefined;
+  }
+
+  if (decoratorNode.parent.superClass?.type !== TSESTree.AST_NODE_TYPES.Identifier) {
+    return undefined;
+  }
+
+  return decoratorNode.parent.superClass.name;
+}
+
+export function getComponentInitializer(componentDecoratorNode: TSESTree.Decorator): TSESTree.ObjectExpression {
+  return (componentDecoratorNode.expression as TSESTree.CallExpression).arguments[0] as TSESTree.ObjectExpression;
+}
+
+export function getComponentInitializerNodeByName(componentDecoratorNode: TSESTree.Decorator, name: string): TSESTree.Node | undefined {
+  const initializer = getComponentInitializer(componentDecoratorNode);
+  return getObjectPropertyNodeByName(initializer, name);
+}
+
 export function isPartOfViewChild(node: TSESTree.Identifier): boolean {
   return (node.parent as any)?.callee?.name === 'ViewChild';
 }

lint/src/util/fix.ts

@@ -0,0 +1,125 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+import { TSESTree } from '@typescript-eslint/utils';
+import {
+  RuleContext,
+  RuleFix,
+  RuleFixer,
+} from '@typescript-eslint/utils/ts-eslint';
+
+import { getSourceCode } from './typescript';
+
+
+
+export function appendObjectProperties(context: RuleContext<any, any>, fixer: RuleFixer, objectNode: TSESTree.ObjectExpression, properties: string[]): RuleFix {
+  // todo: may not handle empty objects too well
+  const lastProperty = objectNode.properties[objectNode.properties.length - 1];
+  const source = getSourceCode(context);
+  const nextToken = source.getTokenAfter(lastProperty);
+
+  // todo: newline & indentation are hardcoded for @Component({})
+  // todo: we're assuming that we need trailing commas, what if we don't?
+  const newPart = '\n' + properties.map(p => `  ${p},`).join('\n');
+
+  if (nextToken !== null && nextToken.value === ',') {
+    return fixer.insertTextAfter(nextToken, newPart);
+  } else {
+    return fixer.insertTextAfter(lastProperty, ',' + newPart);
+  }
+}
+
+export function appendArrayElement(context: RuleContext<any, any>, fixer: RuleFixer, arrayNode: TSESTree.ArrayExpression, value: string): RuleFix {
+  const source = getSourceCode(context);
+
+  if (arrayNode.elements.length === 0) {
+    // This is the first element
+    const openArray = source.getTokenByRangeStart(arrayNode.range[0]);
+
+    if (openArray == null) {
+      throw new Error('Unexpected null token for opening square bracket');
+    }
+
+    // safe to assume the list is single-line
+    return fixer.insertTextAfter(openArray, `${value}`);
+  } else {
+    const lastElement = arrayNode.elements[arrayNode.elements.length - 1];
+
+    if (lastElement == null) {
+      throw new Error('Unexpected null node in array');
+    }
+
+    const nextToken = source.getTokenAfter(lastElement);
+
+    // todo: we don't know if the list is chopped or not, so we can't make any assumptions -- may produce output that will be flagged by other rules on the next run!
+    // todo: we're assuming that we need trailing commas, what if we don't?
+    if (nextToken !== null && nextToken.value === ',') {
+      return fixer.insertTextAfter(nextToken, ` ${value},`);
+    } else {
+      return fixer.insertTextAfter(lastElement, `, ${value},`);
+    }
+  }
+
+}
+
+export function isLast(elementNode: TSESTree.Node): boolean {
+  if (!elementNode.parent) {
+    return false;
+  }
+
+  let siblingNodes: (TSESTree.Node | null)[] = [null];
+  if (elementNode.parent.type === TSESTree.AST_NODE_TYPES.ArrayExpression) {
+    siblingNodes = elementNode.parent.elements;
+  } else if (elementNode.parent.type === TSESTree.AST_NODE_TYPES.ImportDeclaration) {
+    siblingNodes = elementNode.parent.specifiers;
+  }
+
+  return elementNode === siblingNodes[siblingNodes.length - 1];
+}
+
+export function removeWithCommas(context: RuleContext<any, any>, fixer: RuleFixer, elementNode: TSESTree.Node): RuleFix[] {
+  const ops = [];
+
+  const source = getSourceCode(context);
+  let nextToken = source.getTokenAfter(elementNode);
+  let prevToken = source.getTokenBefore(elementNode);
+
+  if (nextToken !== null && prevToken !== null) {
+    if (nextToken.value === ',') {
+      nextToken = source.getTokenAfter(nextToken);
+      if (nextToken !== null) {
+        ops.push(fixer.removeRange([elementNode.range[0], nextToken.range[0]]));
+      }
+    }
+    if (isLast(elementNode) && prevToken.value === ',') {
+      prevToken = source.getTokenBefore(prevToken);
+      if (prevToken !== null) {
+        ops.push(fixer.removeRange([prevToken.range[1], elementNode.range[1]]));
+      }
+    }
+  } else if (nextToken !== null) {
+    ops.push(fixer.removeRange([elementNode.range[0], nextToken.range[0]]));
+  }
+
+  return ops;
+}
+
+export function replaceOrRemoveArrayIdentifier(context: RuleContext<any, any>, fixer: RuleFixer, identifierNode: TSESTree.Identifier, newValue: string): RuleFix[] {
+  if (identifierNode.parent.type !== TSESTree.AST_NODE_TYPES.ArrayExpression) {
+    throw new Error('Parent node is not an array expression!');
+  }
+
+  const array = identifierNode.parent as TSESTree.ArrayExpression;
+
+  for (const element of array.elements) {
+    if (element !== null && element.type === TSESTree.AST_NODE_TYPES.Identifier && element.name === newValue) {
+      return removeWithCommas(context, fixer, identifierNode);
+    }
+  }
+
+  return [fixer.replaceText(identifierNode, newValue)];
+}

lint/src/util/theme-support.ts

@@ -11,7 +11,10 @@ import { readFileSync } from 'fs';
 import { basename } from 'path';
 import ts, { Identifier } from 'typescript';
 
-import { isPartOfViewChild } from './angular';
+import {
+  getComponentClassName,
+  isPartOfViewChild,
+} from './angular';
 import {
   AnyRuleContext,
   getFilename,
@@ -74,12 +77,14 @@ function findImportDeclaration(source: ts.SourceFile, identifierName: string): t
 class ThemeableComponentRegistry {
   public readonly entries: Set<ThemeableComponentRegistryEntry>;
   public readonly byBaseClass: Map<string, ThemeableComponentRegistryEntry>;
+  public readonly byWrapperClass: Map<string, ThemeableComponentRegistryEntry>;
   public readonly byBasePath: Map<string, ThemeableComponentRegistryEntry>;
   public readonly byWrapperPath: Map<string, ThemeableComponentRegistryEntry>;
 
   constructor() {
     this.entries = new Set();
     this.byBaseClass = new Map();
+    this.byWrapperClass = new Map();
     this.byBasePath = new Map();
     this.byWrapperPath = new Map();
   }
@@ -157,6 +162,7 @@ class ThemeableComponentRegistry {
   private add(entry: ThemeableComponentRegistryEntry) {
     this.entries.add(entry);
     this.byBaseClass.set(entry.baseClass, entry);
+    this.byWrapperClass.set(entry.wrapperClass, entry);
     this.byBasePath.set(entry.basePath, entry);
     this.byWrapperPath.set(entry.wrapperPath, entry);
   }
@@ -206,6 +212,23 @@ export function isThemedComponentWrapper(decoratorNode: TSESTree.Decorator): boo
   return (decoratorNode.parent.superClass as any)?.name === 'ThemedComponent';
 }
 
+export function getBaseComponentClassName(decoratorNode: TSESTree.Decorator): string | undefined {
+  const wrapperClass = getComponentClassName(decoratorNode);
+
+  if (wrapperClass === undefined) {
+    return;
+  }
+
+  themeableComponents.initialize();
+  const entry = themeableComponents.byWrapperClass.get(wrapperClass);
+
+  if (entry === undefined) {
+    return undefined;
+  }
+
+  return entry.baseClass;
+}
+
 export function isThemeableComponent(className: string): boolean {
   themeableComponents.initialize();
   return themeableComponents.byBaseClass.has(className);

lint/src/util/typescript.ts

@@ -64,6 +64,24 @@ export function findUsages(context: AnyRuleContext, localNode: TSESTree.Identifi
   return usages;
 }
 
+export function findUsagesByName(context: AnyRuleContext, identifier: string): TSESTree.Identifier[] {
+  const source = getSourceCode(context);
+
+  const usages: TSESTree.Identifier[] = [];
+
+  for (const token of source.ast.tokens) {
+    if (token.type === 'Identifier' && token.value === identifier) {
+      const node = source.getNodeByRangeIndex(token.range[0]);
+      // todo: in some cases, the resulting node can actually be the whole program (!)
+      if (node !== null) {
+        usages.push(node as TSESTree.Identifier);
+      }
+    }
+  }
+
+  return usages;
+}
+
 export function isPartOfTypeExpression(node: TSESTree.Identifier): boolean {
   return node.parent?.type?.startsWith('TSType');
 }
@@ -71,3 +89,59 @@ export function isPartOfTypeExpression(node: TSESTree.Identifier): boolean {
 export function isPartOfClassDeclaration(node: TSESTree.Identifier): boolean {
   return node.parent?.type === 'ClassDeclaration';
 }
+
+function fromSrc(path: string): string {
+  const m = path.match(/^.*(src\/.+)(\.(ts|json|js)?)$/);
+
+  if (m) {
+    return m[1];
+  } else {
+    throw new Error(`Can't infer project-absolute TS/resource path from: ${path}`);
+  }
+}
+
+
+export function relativePath(thisFile: string, importFile: string): string {
+  const fromParts = fromSrc(thisFile).split('/');
+  const toParts = fromSrc(importFile).split('/');
+
+  let lastCommon = 0;
+  for (let i = 0; i < fromParts.length - 1; i++) {
+    if (fromParts[i] === toParts[i]) {
+      lastCommon++;
+    } else {
+      break;
+    }
+  }
+
+  const path = toParts.slice(lastCommon, toParts.length).join('/');
+  const backtrack = fromParts.length - lastCommon - 1;
+
+  let prefix: string;
+  if (backtrack > 0) {
+    prefix = '../'.repeat(backtrack);
+  } else {
+    prefix = './';
+  }
+
+  return prefix + path;
+}
+
+
+export function findImportSpecifier(context: AnyRuleContext, identifier: string): TSESTree.ImportSpecifier | undefined {
+  const source = getSourceCode(context);
+
+  const usages: TSESTree.Identifier[] = [];
+
+  for (const token of source.ast.tokens) {
+    if (token.type === 'Identifier' && token.value === identifier) {
+      const node = source.getNodeByRangeIndex(token.range[0]);
+      // todo: in some cases, the resulting node can actually be the whole program (!)
+      if (node && node.parent && node.parent.type === TSESTree.AST_NODE_TYPES.ImportSpecifier) {
+        return node.parent;
+      }
+    }
+  }
+
+  return undefined;
+}

lint/test/fixture/src/app/test/test-themeable.component.ts

@@ -10,6 +10,7 @@ import { Component } from '@angular/core';
 @Component({
   selector: 'ds-base-test-themeable',
   template: '',
+  standalone: true,
 })
 export class TestThemeableComponent {
 }

lint/test/fixture/src/app/test/themed-test-themeable.component.ts

@@ -13,6 +13,8 @@ import { TestThemeableComponent } from './test-themeable.component';
 @Component({
   selector: 'ds-test-themeable',
   template: '',
+  standalone: true,
+  imports: [TestThemeableComponent],
 })
 export class ThemedTestThemeableComponent extends ThemedComponent<TestThemeableComponent> {
   protected getComponentName(): string {

lint/test/fixture/src/themes/test/app/test/other-themeable.component.ts

@@ -0,0 +1,16 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+import { Component } from '@angular/core';
+
+@Component({
+  selector: 'ds-themed-test-themeable',
+  template: '',
+})
+export class OtherThemeableComponent {
+
+}

lint/test/fixture/src/themes/test/test.module.ts

@@ -8,11 +8,13 @@
 // @ts-ignore
 import { NgModule } from '@angular/core';
 
+import { OtherThemeableComponent } from './app/test/other-themeable.component';
 import { TestThemeableComponent } from './app/test/test-themeable.component';
 
 @NgModule({
   declarations: [
     TestThemeableComponent,
+    OtherThemeableComponent,
   ],
 })
 export class TestModule {

lint/test/fixture/tsconfig.json

@@ -1,6 +1,7 @@
 {
   "extends": "../../../tsconfig.json",
   "include": [
+    "src/**/*.ts",
     "src/**/*.ts"
   ],
   "exclude": ["dist"]

lint/test/testing.ts

@@ -20,6 +20,7 @@ import {
 themeableComponents.initialize(FIXTURE);
 
 TypeScriptRuleTester.itOnly = fit;
+TypeScriptRuleTester.itSkip = xit;
 
 export const tsRuleTester = new TypeScriptRuleTester({
   parser: '@typescript-eslint/parser',