Add ESLint rule ensuring peerDependencies are also declared in devDependencies

.changeset/clever-ghosts-smell.md

@@ -0,0 +1,7 @@
+---
+"@naverpay/eslint-plugin": minor
+---
+
+Add ESLint rule ensuring peerDependencies are also declared in devDependencies
+
+PR: [Add ESLint rule ensuring peerDependencies are also declared in devDependencies](https://github.com/NaverPayDev/code-style/pull/90)

packages/eslint-plugin/lib/index.js

@@ -2,6 +2,7 @@ import pkg from '../package.json'
 import importServerOnly from './rules/import-server-only'
 import memoReactComponents from './rules/memo-react-components.js'
 import optimizeSvgComponents from './rules/optimize-svg-components.js'
+import peerDepsInDevDeps from './rules/peer-deps-in-dev-deps.js'
 import preventDefaultImport from './rules/prevent-default-import.js'
 import sortExports from './rules/sort-exports.js'
 import svgUniqueId from './rules/svg-unique-id.js'
@@ -18,6 +19,7 @@ const plugin = {
         'sort-exports': sortExports,
         'svg-unique-id': svgUniqueId,
         'import-server-only': importServerOnly,
+        'peer-deps-in-dev-deps': peerDepsInDevDeps,
     },
 }
 

packages/eslint-plugin/lib/rules/peer-deps-in-dev-deps.js.js

@@ -0,0 +1,51 @@
+import path from 'path'
+
+export default {
+    meta: {
+        type: 'problem',
+        docs: {
+            description: 'Ensure that all peerDependencies are also declared in devDependencies.',
+            recommended: false,
+        },
+        fixable: null,
+        schema: [],
+        messages: {
+            missingInDevDeps: "'{{packageName}}' is declared in peerDependencies but not in devDependencies.",
+        },
+    },
+
+    create(context) {
+        return {
+            Program(node) {
+                const filename = path.basename(context.getFilename())
+                if (filename !== 'package.json') {
+                    return
+                }
+
+                const sourceCode = context.getSourceCode().getText()
+                let json
+
+                try {
+                    json = JSON.parse(sourceCode)
+                } catch (error) {
+                    // eslint-disable-next-line no-console
+                    console.error('Failed to parse package.json:', error)
+                    return
+                }
+
+                const peerDeps = json.peerDependencies || {}
+                const devDeps = json.devDependencies || {}
+
+                for (const [depName] of Object.entries(peerDeps)) {
+                    if (!Object.prototype.hasOwnProperty.call(devDeps, depName)) {
+                        context.report({
+                            node,
+                            messageId: 'missingInDevDeps',
+                            data: {packageName: depName},
+                        })
+                    }
+                }
+            },
+        }
+    },
+}