feat(valid-files): add new rule for validating files (#1380)

<!-- 👋 Hi, thanks for sending a PR to eslint-plugin-package-json! 🗂 Please fill out all fields below and make sure each item is true and [x] checked. Otherwise we may not be able to review your PR. --> ## PR Checklist - [x] Addresses an existing open issue: fixes #827 - [x] That issue was marked as [`status: accepting prs`](https://github.com/JoshuaKGoldberg/eslint-plugin-package-json/issues?q=is%3Aopen+is%3Aissue+label%3A%22status%3A+accepting+prs%22) - [x] Steps in [CONTRIBUTING.md](https://github.com/JoshuaKGoldberg/eslint-plugin-package-json/blob/main/.github/CONTRIBUTING.md) were taken ## Overview This change adds a new `valid-files` rule that uses `validateFiles` from package-json-validator to identify errors. It's included in the `recommended` config.

Author: michaelfaith

README.md

@@ -221,6 +221,7 @@ The default settings don't conflict, and Prettier plugins can quickly fix up ord
 | [valid-devDependencies](docs/rules/valid-devDependencies.md) | Enforce that the `devDependencies` property is valid. | ✔️ ✅ | | | |
 | [valid-directories](docs/rules/valid-directories.md) | Enforce that the `directories` property is valid. | ✔️ ✅ | | | |
 | [valid-exports](docs/rules/valid-exports.md) | Enforce that the `exports` property is valid. | ✔️ ✅ | | | |
+| [valid-files](docs/rules/valid-files.md) | Enforce that the `files` property is valid. | ✔️ ✅ | | | |
 | [valid-homepage](docs/rules/valid-homepage.md) | Enforce that the `homepage` property is valid. | ✔️ ✅ | | | |
 | [valid-license](docs/rules/valid-license.md) | Enforce that the `license` property is valid. | ✔️ ✅ | | | |
 | [valid-local-dependency](docs/rules/valid-local-dependency.md) | Checks existence of local dependencies in the package.json | | | | ❌ |

docs/rules/valid-files.md

@@ -0,0 +1,26 @@
+# valid-files
+
+💼 This rule is enabled in the following configs: ✔️ `legacy-recommended`, ✅ `recommended`.
+
+<!-- end auto-generated rule header -->
+
+This rule does the following checks on the value of the `files` property:
+
+- It must be an array.
+- The array should only consist of non-empty strings
+
+Example of **incorrect** code for this rule:
+
+```json
+{
+"files": "dist/*"
+}
+```
+
+Example of **correct** code for this rule:
+
+```json
+{
+"files": ["CHANGELOG.md", "dist/"]
+}
+```

package.json

@@ -60,7 +60,7 @@
 "detect-indent": "^7.0.2",
 "detect-newline": "^4.0.1",
 "eslint-fix-utils": "~0.4.0",
-"package-json-validator": "~0.57.0",
+"package-json-validator": "~0.58.0",
 "semver": "^7.7.3",
 "sort-object-keys": "^2.0.0",
 "sort-package-json": "^3.4.0",

pnpm-lock.yaml

@@ -8,6 +8,7 @@ import {
 validateDescription,
 validateDirectories,
 validateExports,
+validateFiles,
 validateHomepage,
 validateLicense,
 validateScripts,
@@ -43,6 +44,7 @@ const properties = [
 ["devDependencies", validateDependencies],
 ["directories", validateDirectories],
 ["exports", validateExports],
+["files", validateFiles],
 ["homepage", validateHomepage],
 ["license", validateLicense],
 ["optionalDependencies", validateDependencies],

src/rules/valid-properties.ts

@@ -0,0 +1,112 @@
+import { rules } from "../../rules/valid-properties.ts";
+import { ruleTester } from "./ruleTester.ts";
+
+ruleTester.run("valid-files", rules["valid-files"], {
+invalid: [
+{
+code: `{
+"files": null
+}
+`,
+errors: [
+{
+data: {
+error: "the value is `null`, but should be an `Array` of strings",
+},
+line: 2,
+messageId: "validationError",
+},
+],
+},
+{
+code: `{
+"files": 123
+}
+`,
+errors: [
+{
+data: {
+error: "the type should be `Array`, not `number`",
+},
+line: 2,
+messageId: "validationError",
+},
+],
+},
+{
+code: `{
+"files": "invalid"
+}
+`,
+errors: [
+{
+data: {
+error: "the type should be `Array`, not `string`",
+},
+line: 2,
+messageId: "validationError",
+},
+],
+},
+{
+code: `{
+"files": {
+ "invalid-bin": 123
+ }
+}
+`,
+errors: [
+{
+data: {
+error: "the type should be `Array`, not `object`",
+},
+line: 2,
+messageId: "validationError",
+},
+],
+},
+{
+code: `{
+"files": [
+ "valid",
+ "",
+ 123,
+ null,
+ {}
+ ]
+}
+`,
+errors: [
+{
+data: {
+error: "item at index 1 is empty, but should be a file pattern",
+},
+line: 4,
+messageId: "validationError",
+},
+{
+data: {
+error: "item at index 2 should be a string, not `number`",
+},
+line: 5,
+messageId: "validationError",
+},
+{
+data: {
+error: "item at index 3 should be a string, not `null`",
+},
+line: 6,
+messageId: "validationError",
+},
+{
+data: {
+error: "item at index 4 should be a string, not `object`",
+},
+line: 7,
+messageId: "validationError",
+},
+],
+},
+],
+valid: ["{}", `{ "files": [] }`, `{ "files": ["CHANGELOG.md", "dist/"] }`],
+});