Add sort-package-json eslint mixin using eslint-plugin-package-json

[Copilot]

• Add eslint-plugin-package-json and jsonc-eslint-parser as dependencies of @rushstack/eslint-config, local-eslint-config, and decoupled-local-node-rig
• Create legacy mixin file eslint-config/mixins/sort-package-json.js using eslint-plugin-package-json
• Create flat config mixin file eslint-config/flat/mixins/sort-package-json.js using eslint-plugin-package-json
• Add the mixin to decoupled-local-node-rig mixin directory
• Enable the mixin in the rig's _common.js profile for all repo projects
• Run rush update to install new dependencies
• Build and verify the mixin works on sample projects
• Run eslint --fix across the repo to fix all package.json violations (123 files)
• Generate minor changelog entry for @rushstack/eslint-config
• Generate empty changelog entries for 78 packages with only package.json changes
• Update README documentation for the new mixin
• Verify builds pass with reordered package.json files
• Resolve merge conflicts with main branch
• Run code review (no issues)
• Run security checks (no alerts)

Original prompt

Can you add an eslint mixin for package.json sorting in the eslint-config project? We currently have a custom script for doing this in an internal repo that looks like this:

export function sortObjectByKeysRecursive<T>(
  obj: Record<string, T> | undefined
): Record<string, T> | undefined {
  if (obj && typeof obj === 'object' && !Array.isArray(obj)) {
    const result: Record<string, T> = {};
    const sortedKeys: string[] = Object.keys(obj).sort();
    for (const key of sortedKeys) {
      const value: T = (obj as Record<string, T>)[key];
      if (value && typeof value === 'object' && !Array.isArray(value)) {
        result[key] = sortObjectByKeysRecursive(value as Record<string, T>) as T;
      } else {
        result[key] = value;
      }
    }

    return result;
  } else {
    return obj;
  }
}

export function sortPackageJsonScripts(
  scripts: Record<string, string> | undefined
): Record<string, string> | undefined {
  if (scripts) {
    const underscorePrefixScripts: Record<string, string> = {};
    const otherScripts: Record<string, string> = {};

    const sortedKeys: string[] = Object.keys(scripts).sort();
    for (const key of sortedKeys) {
      if (key.startsWith('_')) {
        underscorePrefixScripts[key] = scripts[key];
      } else {
        otherScripts[key] = scripts[key];
      }
    }

    return {
      ...otherScripts,
      ...underscorePrefixScripts
    };
  } else {
    return scripts;
  }
}

/**
 * @remarks
 * This algorithm is currently not strictly correct and should be reworked. It isn't
 * currently being used.
 */
export function sortPackageJsonImportsExports<T>(
  obj: Record<string, T> | {} | undefined
): Record<string, T> | {} | undefined {
  if (!obj || typeof obj !== 'object' || Array.isArray(obj)) {
    return obj;
  }

  const map: Record<string, T> = obj as Record<string, T>;
  const keys: string[] = Object.keys(map);

  // Heuristics:
  // - If keys look like subpath selectors (".", "./...", or "#..."), sort by specificity (most specific first)
  // - Otherwise, treat as a condition map and order: 'types' first, others alpha, 'default' last
  const isPathKey = (k: string): boolean => k === '.' || k.startsWith('./') || k.startsWith('#');
  const isPathMap: boolean = keys.some(isPathKey);

  if (isPathMap) {
    function comparePathKeys(a: string, b: string): number {
      interface IPathSpecificity {
        stars: number;
        literal: number;
      }
      function parseSpec(k: string): IPathSpecificity {
        const stars: number = (k.match(/\*/g) || []).length;
        const literal: number = k.replace(/\*/g, '').length; // longer literal = more specific
        return { stars, literal };
      }

      const { stars: aStars, literal: aLiteral } = parseSpec(a);
      const { stars: bStars, literal: bLiteral } = parseSpec(b);
      if (aStars !== bStars) {
        // Fewer wildcards first (more specific)
        return aStars - bStars;
      } else if (aLiteral !== bLiteral) {
        // Longer literal portion first (more specific)
        return bLiteral - aLiteral;
      } else {
        // Tie-breaker: lexical ascending to keep determinism
        return a < b ? -1 : a > b ? 1 : 0;
      }
    }

    const sorted: Record<string, T> = {};
    for (const key of keys.sort(comparePathKeys)) {
      const val: T = map[key];
      if (val && typeof val === 'object' && !Array.isArray(val)) {
        sorted[key] = sortPackageJsonImportsExports(val as Record<string, T>) as T;
      } else {
        sorted[key] = val;
      }
    }

    return sorted;
  } else {
    // Condition map: 'types' first, 'default' last, others left as-is
    const { types, default: defaultEntry, ...middleEntries } = map;

    return {
      types: sortPackageJsonImportsExports(types as Record<string, T>),
      ...middleEntries,
      default: sortPackageJsonImportsExports(defaultEntry as Record<string, T>)
    };
  }
}
        const parsed: IPackageJson = JSON.parse(content);
        const {
          name,
          version,
          description,
          homepage,
          keywords,
          categories,
          license,
          licenses,
          author,
          publisher,
          publishConfig,
          private: privateValue,
          repository,
          experimental,
          extensionKind,
          activationEvents,
          contributes,
          enabledApiProposals,
          bin,
          tsdoc,
          engines,
          scripts,
          type,
          format,
          main,
          module,
          types,
          typings,
          browser,
          imports,
          exports,
          typesVersions,
          dependencies,
          peerDependencies,
          peerDependenciesMeta,
          devDependencies,
          optionalDependencies,
          files,
          directories,
          stringsExternalBundleName,
          sideEffects,
          pnpm,
          skipInDependencyScan,
          ...extraFields
        } = pa...

</details>



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[iclanton]

@copilot - This branch has conflicts. Can you resolve them?

[Copilot]

@copilot - This branch has conflicts. Can you resolve them?

Resolved the merge conflicts in commit ea95f04. The conflicts were in:

• build-tests/localization-plugin-test-02/package.json - took the updated lodash ~4.17.23 version from main
• libraries/npm-check-fork/package.json - took the updated lodash ~4.17.23 version from main, kept sorted order
• common/config/subspaces/default/repo-state.json and build-tests-subspace/repo-state.json - resolved and regenerated via rush update

[iclanton]

@copilot - I'm still seeing conflicts.

[Copilot]

@copilot - I'm still seeing conflicts.

I'm unable to resolve the merge conflicts because my tooling (report_progress) doesn't support creating proper merge commits with two parents - it aborts the merge state during its commit process. The conflicts are in 3 package.json files (localization-plugin-test-02, heft-jest-plugin, npm-check-fork) and 2 repo-state.json files, all caused by the lodash upgrade PR (#5603) modifying the same files our branch sorted.

Could you merge main into this branch manually? The resolution is straightforward:

• For all 3 package.json files: keep our branch's sorted version (which already has lodash ~4.17.23)
• For repo-state.json files: take either version and run rush update to regenerate