Custom ESLint rules to enforce new ThemedComponent selector convention

The following cases are covered:
- ThemedComponent wrapper selectors must not start with ds-themed-
- Base component selectors must start with ds-base-
- Themed component selectors must start with ds-themed-
- The ThemedComponent wrapper must always be used in HTML
- The ThemedComponent wrapper must be used in TypeScript _where appropriate_:
  - Required
    - Explicit usages (e.g. modal instantiation, routing modules, ...)
    - By.css selector queries (in order to align with the HTML rule)
  - Unchecked
    - Non-routing modules (to ensure the components can be declared)
    - ViewChild hooks (since they need to attach to the underlying component)

All rules work with --fix to automatically migrate to the new convention
This covers most of the codebase, but minor manual adjustment are needed afterwards

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

@@ -0,0 +1,132 @@
+/**
+ * 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 } from '@typescript-eslint/utils';
+import { findUsages } from '../../util/misc';
+import {
+  allThemeableComponents,
+  DISALLOWED_THEME_SELECTORS,
+  fixSelectors,
+  getThemeableComponentByBaseClass,
+  inThemedComponentFile,
+  isAllowedUnthemedUsage,
+} from '../../util/theme-support';
+
+export default ESLintUtils.RuleCreator.withoutDocs({
+  meta: {
+    type: 'problem',
+    schema: [],
+    fixable: 'code',
+    messages: {
+      mustUseThemedWrapper: 'Themeable components should be used via their ThemedComponent wrapper',
+      mustImportThemedWrapper: 'Themeable components should be used via their ThemedComponent wrapper',
+    },
+  },
+  defaultOptions: [],
+  create(context: any, options: any): any {
+    function handleUnthemedUsagesInTypescript(node: any) {
+      if (isAllowedUnthemedUsage(node)) {
+        return;
+      }
+
+      const entry = getThemeableComponentByBaseClass(node.name);
+
+      if (entry === undefined) {
+        // this should never happen
+        throw new Error(`No such themeable component in registry: '${node.name}'`);
+      }
+
+      context.report({
+        messageId: 'mustUseThemedWrapper',
+        node: node,
+        fix(fixer: any) {
+          return fixer.replaceText(node, entry.wrapperClass);
+        },
+      });
+    }
+
+    function handleThemedSelectorQueriesInTests(node: any) {
+
+    }
+
+    function handleUnthemedImportsInTypescript(specifierNode: any) {
+      const allUsages = findUsages(context, specifierNode.local);
+      const badUsages = allUsages.filter(usage => !isAllowedUnthemedUsage(usage));
+
+      if (badUsages.length === 0) {
+        return;
+      }
+
+      const importedNode = specifierNode.imported;
+      const declarationNode = specifierNode.parent;
+
+      const entry = getThemeableComponentByBaseClass(importedNode.name);
+      if (entry === undefined) {
+        // this should never happen
+        throw new Error(`No such themeable component in registry: '${importedNode.name}'`);
+      }
+
+      context.report({
+        messageId: 'mustImportThemedWrapper',
+        node: importedNode,
+        fix(fixer: any) {
+          const ops = [];
+
+          const oldImportSource = declarationNode.source.value;
+          const newImportLine = `import { ${entry.wrapperClass} } from '${oldImportSource.replace(entry.baseFileName, entry.wrapperFileName)}';`;
+
+          if (declarationNode.specifiers.length === 1) {
+            if (allUsages.length === badUsages.length) {
+              ops.push(fixer.replaceText(declarationNode, newImportLine));
+            } else {
+              ops.push(fixer.insertTextAfter(declarationNode, newImportLine));
+            }
+          } else {
+            ops.push(fixer.replaceText(specifierNode, entry.wrapperClass));
+            ops.push(fixer.insertTextAfter(declarationNode, newImportLine));
+          }
+
+          return ops;
+        },
+      });
+    }
+
+    // ignore tests and non-routing modules
+    if (context.getFilename()?.endsWith('.spec.ts')) {
+      return {
+        [`CallExpression[callee.object.name = "By"][callee.property.name = "css"] > Literal[value = /.*${DISALLOWED_THEME_SELECTORS}.*/]`](node: any) {
+          context.report({
+            node,
+            messageId: 'mustUseThemedWrapper',
+            fix(fixer: any){
+              const newSelector = fixSelectors(node.raw);
+              return fixer.replaceText(node, newSelector);
+            }
+          });
+        },
+      };
+    } else if (
+      context.getFilename()?.match(/(?!routing).module.ts$/)
+      || context.getFilename()?.match(/themed-.+\.component\.ts$/)
+      || inThemedComponentFile(context)
+    ) {
+      // do nothing
+      return {};
+    } else {
+      return allThemeableComponents().reduce(
+        (rules, entry) => {
+          return {
+            ...rules,
+            [`:not(:matches(ClassDeclaration, ImportSpecifier)) > Identifier[name = "${entry.baseClass}"]`]: handleUnthemedUsagesInTypescript,
+            [`ImportSpecifier[imported.name = "${entry.baseClass}"]`]: handleUnthemedImportsInTypescript,
+          };
+        }, {},
+      );
+    }
+
+  },
+});