@atlaskit/eslint-plugin-design-system/dist/es2019/rules/no-unused-css-map/unused-css-map-checker.js

The essential plugin for use with the Atlassian Design System.

import { getSourceCode } from '@atlaskit/eslint-utils/context-compat';
import { findVariable } from '@atlaskit/eslint-utils/find-variable';
export class UnusedCssMapChecker {
  constructor(cssMapObject, context, cssMapCallNode) {
    this.cssMapObject = cssMapObject;
    this.cssMapCallNode = cssMapCallNode;
    this.report = context.report;
    this.context = context;
  }
  checkForUnusedStyles() {
    // Get all defined style keys
    const definedStyles = new Map();
    for (const property of this.cssMapObject.properties) {
      if (property.type === 'Property' && property.key.type === 'Identifier') {
        definedStyles.set(property.key.name, property);
      }
    }
    if (definedStyles.size === 0) {
      return;
    }

    // Find the variable that holds the cssMap result
    const cssMapVariable = this.findCssMapVariable();
    if (!cssMapVariable) {
      return;
    }

    // Early return if no references - all styles are unused
    if (cssMapVariable.references.length === 0) {
      for (const [styleName, property] of definedStyles) {
        this.report({
          node: property.key,
          messageId: 'unusedCssMapStyle',
          data: {
            styleName
          }
        });
      }
      return;
    }
    const usedStyles = new Set();
    for (const ref of cssMapVariable.references) {
      const node = ref.identifier;
      const parent = node.parent;
      if ((parent === null || parent === void 0 ? void 0 : parent.type) === 'MemberExpression') {
        if (!parent.computed && parent.property.type === 'Identifier') {
          // Static access: styles.danger (not computed)
          usedStyles.add(parent.property.name);

          // Early exit if all styles are found
          if (usedStyles.size === definedStyles.size) {
            return;
          }
        } else {
          // Dynamic access: styles[key], styles['danger'], etc. (computed)
          // Immediately exit - no styles will be reported as unused
          return;
        }
      }
    }

    // No dynamic access - report all unused styles
    for (const [styleName, property] of definedStyles) {
      if (!usedStyles.has(styleName)) {
        this.report({
          node: property.key,
          messageId: 'unusedCssMapStyle',
          data: {
            styleName
          }
        });
      }
    }
  }
  findCssMapVariable() {
    const callNode = this.cssMapCallNode;
    const parent = callNode.parent;
    if ((parent === null || parent === void 0 ? void 0 : parent.type) === 'VariableDeclarator' && parent.id.type === 'Identifier') {
      return findVariable({
        identifier: parent.id,
        sourceCode: getSourceCode(this.context)
      });
    }
    return null;
  }
  run() {
    this.checkForUnusedStyles();
  }
}