feat: validate type comments and generate .d.ts

.eslintignore

@@ -7,3 +7,4 @@
 !.vitepress
 /docs/.vitepress/dist
 /docs/.vitepress/cache
+/dist

.eslintrc.js

@@ -4,7 +4,12 @@
 module.exports = {
     root: true,
     extends: ["plugin:@eslint-community/mysticatea/es2020"],
+    parserOptions: {
+        project: true,
+    },
     rules: {
+        semi: ["error", "never"],
+        "semi-spacing": ["error", { before: false, after: true }],
         "@eslint-community/mysticatea/prettier": "off",
         "no-restricted-properties": [
             "error",
@@ -18,7 +23,7 @@ module.exports = {
     },
     overrides: [
         {
-            files: ["src/**/*.mjs", "test/**/*.mjs"],
+            files: ["src/**/*.mjs", "test/**/*.mjs", "rollup.config.mjs"],
             extends: ["plugin:@eslint-community/mysticatea/+modules"],
             rules: {
                 "init-declarations": "off",

.github/workflows/ci.yml

@@ -39,6 +39,9 @@ jobs:
             - name: ▶️ Run lint script
               run: npm run lint
 
+            - name: 🏗 Build
+              run: npm run build
+
     test:
         name:
             🧪 Test (Node@${{ matrix.node }} - ESLint@${{ matrix.eslint }} - ${{
@@ -83,9 +86,6 @@ jobs:
             - name: 📥 Install ESLint v${{ matrix.eslint }}
               run: npm install --save-dev eslint@${{ matrix.eslint }}
 
-            - name: 🏗 Build
-              run: npm run build
-
             - name: ▶️ Run test script
               run: npm run test
 

.gitignore

@@ -5,3 +5,4 @@
 /node_modules
 /index.*
 /test.*
+/dist

declaration.tsconfig.json

@@ -0,0 +1,11 @@
+{
+    "extends": "./tsconfig",
+    "files": [],
+    "exclude": ["tests/**/*.js"],
+    "compilerOptions": {
+        "declaration": true,
+        "emitDeclarationOnly": true,
+        "noEmit": false,
+        "outDir": "dist"
+    }
+}

package.json

@@ -18,27 +18,30 @@
     "sideEffects": false,
     "exports": {
         ".": {
-            "import": "./index.mjs",
-            "require": "./index.js"
-        },
-        "./package.json": "./package.json"
+            "types": "./index.d.ts",
+            "default": "./index.js"
+        }
     },
-    "main": "index",
-    "module": "index.mjs",
+    "main": "index.js",
+    "types": "index.d.ts",
     "files": [
-        "index.*"
+        "index.d.ts",
+        "index.js"
     ],
     "scripts": {
-        "prebuild": "npm run -s clean",
-        "build": "rollup -c",
-        "clean": "rimraf .nyc_output coverage index.*",
+        "prebuild": "npm run -s clean ",
+        "build": "tsc -p declaration.tsconfig.json && rollup -c",
+        "clean": "rimraf .nyc_output coverage dist index.*",
         "coverage": "opener ./coverage/lcov-report/index.html",
         "docs:build": "vitepress build docs",
         "docs:watch": "vitepress dev docs",
         "format": "npm run -s format:prettier -- --write",
         "format:prettier": "prettier .",
         "format:check": "npm run -s format:prettier -- --check",
-        "lint": "eslint .",
+        "lint:eslint": "eslint .",
+        "lint:tsc": "tsc",
+        "lint:type-coverage": "type-coverage --detail --strict --at-least 99 --ignore-files 'test/*' --ignore-files 'src/get-static-value.mjs'",
+        "lint": "run-p lint:*",
         "test": "c8 mocha --reporter dot \"test/*.mjs\"",
         "preversion": "npm test && npm run -s build",
         "postversion": "git push && git push --tags",
@@ -50,17 +53,23 @@
     },
     "devDependencies": {
         "@eslint-community/eslint-plugin-mysticatea": "^15.5.1",
+        "@types/eslint": "^8.21.0",
+        "@types/estree": "^1.0.0",
+        "@types/mocha": "^10.0.1",
+        "@types/node": "^18.19.21",
         "c8": "^8.0.1",
         "dot-prop": "^7.2.0",
         "eslint": "^8.50.0",
         "mocha": "^9.2.2",
-        "npm-run-all": "^4.1.5",
+        "npm-run-all2": "^6.1.2",
         "opener": "^1.5.2",
         "prettier": "2.8.8",
         "rimraf": "^3.0.2",
-        "rollup": "^2.79.1",
-        "rollup-plugin-sourcemaps": "^0.6.3",
+        "rollup": "^4.12.0",
+        "rollup-plugin-dts": "^6.1.0",
         "semver": "^7.5.4",
+        "type-coverage": "^2.27.1",
+        "typescript": "^5.3.3",
         "vitepress": "^1.0.0-rc.20",
         "warun": "^1.0.0"
     },

rollup.config.mjs

@@ -0,0 +1,39 @@
+/**
+ * @author Toru Nagashima
+ * See LICENSE file in root directory for full license.
+ */
+
+import { readFileSync } from "node:fs"
+import { URL } from "node:url"
+
+import { dts } from "rollup-plugin-dts"
+
+/** @type {{ dependencies: Record<string, string> }} */
+const packageInfo = JSON.parse(
+    readFileSync(new URL("./package.json", import.meta.url), "utf8"),
+)
+
+export default [
+    {
+        input: "src/index.mjs",
+        output: {
+            exports: "named",
+            file: `index.js`,
+            format: "cjs",
+            sourcemap: true,
+        },
+        external: Object.keys(packageInfo.dependencies),
+    },
+    {
+        input: "dist/index.d.mts",
+        output: [
+            {
+                exports: "named",
+                file: `index.d.ts`,
+                format: "cjs",
+            },
+        ],
+        // type-coverage:ignore-next-line
+        plugins: [dts()],
+    },
+]

src/find-variable.mjs

@@ -2,18 +2,19 @@ import { getInnermostScope } from "./get-innermost-scope.mjs"
 
 /**
  * Find the variable of a given name.
- * @param {Scope} initialScope The scope to start finding.
- * @param {string|Node} nameOrNode The variable name to find. If this is a Node object then it should be an Identifier node.
- * @returns {Variable|null} The found variable or null.
+ * @param {import('eslint').Scope.Scope} initialScope The scope to start finding.
+ * @param {string | import('./types.mjs').Node} nameOrNode The variable name to find. If this is a Node object then it should be an Identifier node.
+ * @returns {import('eslint').Scope.Variable|null} The found variable or null.
  */
 export function findVariable(initialScope, nameOrNode) {
     let name = ""
+    /** @type {import('eslint').Scope.Scope|null} */
     let scope = initialScope
 
     if (typeof nameOrNode === "string") {
         name = nameOrNode
     } else {
-        name = nameOrNode.name
+        name = "name" in nameOrNode ? nameOrNode.name : ""
         scope = getInnermostScope(scope, nameOrNode)
     }
 

src/get-function-head-location.mjs

@@ -2,46 +2,51 @@ import { isArrowToken, isOpeningParenToken } from "./token-predicate.mjs"
 
 /**
  * Get the `(` token of the given function node.
- * @param {Node} node - The function node to get.
- * @param {SourceCode} sourceCode - The source code object to get tokens.
- * @returns {Token} `(` token.
+ * @param {Extract<import('eslint').Rule.Node, { type: 'FunctionDeclaration' | 'FunctionExpression' | 'ArrowFunctionExpression'}>} node - The function node to get.
+ * @param {import('eslint').SourceCode} sourceCode - The source code object to get tokens.
+ * @returns {import('eslint').AST.Token | null} `(` token.
  */
 function getOpeningParenOfParams(node, sourceCode) {
-    return node.id
+    return "id" in node && node.id
         ? sourceCode.getTokenAfter(node.id, isOpeningParenToken)
         : sourceCode.getFirstToken(node, isOpeningParenToken)
 }
 
 /**
  * Get the location of the given function node for reporting.
- * @param {Node} node - The function node to get.
- * @param {SourceCode} sourceCode - The source code object to get tokens.
- * @returns {string} The location of the function node for reporting.
+ * @param {Extract<import('eslint').Rule.Node, { type: 'FunctionDeclaration' | 'FunctionExpression' | 'ArrowFunctionExpression'}>} node - The function node to get.
+ * @param {import('eslint').SourceCode} sourceCode - The source code object to get tokens.
+ * @returns {import('eslint').AST.SourceLocation|null} The location of the function node for reporting.
  */
 export function getFunctionHeadLocation(node, sourceCode) {
-    const parent = node.parent
-    let start = null
-    let end = null
+    const parent = "parent" in node ? node.parent : undefined
+
+    /** @type {import('eslint').AST.SourceLocation["start"]|undefined} */
+    let start,
+        /** @type {import('eslint').AST.SourceLocation["end"]|undefined} */
+        end
 
     if (node.type === "ArrowFunctionExpression") {
         const arrowToken = sourceCode.getTokenBefore(node.body, isArrowToken)
 
-        start = arrowToken.loc.start
-        end = arrowToken.loc.end
+        start = arrowToken?.loc.start
+        end = arrowToken?.loc.end
     } else if (
-        parent.type === "Property" ||
-        parent.type === "MethodDefinition" ||
-        parent.type === "PropertyDefinition"
+        parent?.type === "Property" ||
+        parent?.type === "MethodDefinition" ||
+        parent?.type === "PropertyDefinition"
     ) {
-        start = parent.loc.start
-        end = getOpeningParenOfParams(node, sourceCode).loc.start
+        start = parent.loc?.start
+        end = getOpeningParenOfParams(node, sourceCode)?.loc.start
     } else {
-        start = node.loc.start
-        end = getOpeningParenOfParams(node, sourceCode).loc.start
+        start = node.loc?.start
+        end = getOpeningParenOfParams(node, sourceCode)?.loc.start
     }
 
-    return {
-        start: { ...start },
-        end: { ...end },
-    }
+    return start && end
+        ? {
+              start: { ...start },
+              end: { ...end },
+          }
+        : null
 }

src/get-function-name-with-kind.mjs

@@ -2,13 +2,14 @@ import { getPropertyName } from "./get-property-name.mjs"
 
 /**
  * Get the name and kind of the given function node.
- * @param {ASTNode} node - The function node to get.
- * @param {SourceCode} [sourceCode] The source code object to get the code of computed property keys.
+ * @param {Extract<import('eslint').Rule.Node, { type: 'FunctionDeclaration' | 'FunctionExpression' | 'ArrowFunctionExpression'}>} node - The function node to get.
+ * @param {import('eslint').SourceCode} [sourceCode] The source code object to get the code of computed property keys.
  * @returns {string} The name and kind of the function node.
  */
 // eslint-disable-next-line complexity
 export function getFunctionNameWithKind(node, sourceCode) {
     const parent = node.parent
+    /** @type {string[]} */
     const tokens = []
     const isObjectMethod = parent.type === "Property" && parent.value === node
     const isClassMethod =
@@ -25,10 +26,10 @@ export function getFunctionNameWithKind(node, sourceCode) {
             tokens.push("private")
         }
     }
-    if (node.async) {
+    if ("async" in node && node.async) {
         tokens.push("async")
     }
-    if (node.generator) {
+    if ("generator" in node && node.generator) {
         tokens.push("generator")
     }
 
@@ -68,8 +69,8 @@ export function getFunctionNameWithKind(node, sourceCode) {
                 }
             }
         }
-    } else if (node.id) {
-        tokens.push(`'${node.id.name}'`)
+    } else if ("id" in node && node.id) {
+        tokens.push(`'${"name" in node.id ? node.id.name : undefined}'`)
     } else if (
         parent.type === "VariableDeclarator" &&
         parent.id &&

src/get-innermost-scope.mjs

@@ -1,11 +1,11 @@
 /**
  * Get the innermost scope which contains a given location.
- * @param {Scope} initialScope The initial scope to search.
- * @param {Node} node The location to search.
- * @returns {Scope} The innermost scope.
+ * @param {import('eslint').Scope.Scope} initialScope The initial scope to search.
+ * @param {import('./types.mjs').Node} node The location to search.
+ * @returns {import('eslint').Scope.Scope} The innermost scope.
  */
 export function getInnermostScope(initialScope, node) {
-    const location = node.range[0]
+    const location = node.range ? node.range[0] : undefined
 
     let scope = initialScope
     let found = false
@@ -14,7 +14,12 @@ export function getInnermostScope(initialScope, node) {
         for (const childScope of scope.childScopes) {
             const range = childScope.block.range
 
-            if (range[0] <= location && location < range[1]) {
+            if (
+                range &&
+                location !== undefined &&
+                range[0] <= location &&
+                location < range[1]
+            ) {
                 scope = childScope
                 found = true
                 break