testing-library-detection.ts

import { TSESTree } from '@typescript-eslint/experimental-utils';

/**
 * Enhances a given rule with helpers to detect Testing Library utils.
 */
function testingLibraryDetection(rule: any) {
  return (context: any, options: any) => {
    let isImportingTestingLibrary = false;

    // TODO: init here options based on shared ESLint config

    // helpers for Testing Library detection
    const helpers = {
      getIsImportingTestingLibrary() {
        return isImportingTestingLibrary;
      },
    };

    // instructions for Testing Library detection
    const detectionInstructions = {
      ImportDeclaration(node: TSESTree.ImportDeclaration) {
        isImportingTestingLibrary = /testing-library/g.test(
          node.source.value as string
        );
      },
    };

    // update given rule to inject Testing Library detection
    const ruleInstructions = rule(context, options, helpers);
    const enhancedRuleInstructions = Object.assign({}, ruleInstructions);

    Object.keys(detectionInstructions).forEach((instruction) => {
      enhancedRuleInstructions[instruction] = (node: any) => {
        if (instruction in detectionInstructions) {
          detectionInstructions[instruction](node);
        }

        if (ruleInstructions[instruction]) {
          return ruleInstructions[instruction](node);
        }
      };
    });

    return enhancedRuleInstructions;
  };
}

function detect(rule: any) {
  return testingLibraryDetection(rule);
}

export default detect;