Add strict to tsconfig.json

Author: wooorm

lib/index.js

@@ -22,14 +22,13 @@
 import {embedded} from 'hast-util-embedded'
 import {convertElement} from 'hast-util-is-element'
 import {phrasing} from 'hast-util-phrasing'
+// @ts-expect-error: to do type.
 import toString from 'hast-util-to-string'
 import {whitespace} from 'hast-util-whitespace'
 import {toString as nlcstToString} from 'nlcst-to-string'
 import {pointStart} from 'unist-util-position'
 import vfileLocation from 'vfile-location'
 
-const push = [].push
-
 const source = convertElement(['code', dataNlcstSourced])
 const ignore = convertElement([
   'script',
@@ -181,7 +180,7 @@ export function toNlcst(tree, file, Parser) {
   function implicit(children) {
     let index = -1
     let start = -1
-    /** @type {boolean} */
+    /** @type {boolean|undefined} */
     let viable
 
     while (++index <= children.length) {
@@ -203,7 +202,7 @@ export function toNlcst(tree, file, Parser) {
           find(child)
         }
 
-        viable = null
+        viable = undefined
         start = -1
       }
     }
@@ -213,12 +212,12 @@ export function toNlcst(tree, file, Parser) {
    * Convert `node` (hast) to nlcst.
    *
    * @param {Node} node
-   * @returns {Array.<UnistNode>}
+   * @returns {Array.<UnistNode>|undefined}
    */
   function one(node) {
-    /** @type {Array.<UnistNode>} */
+    /** @type {Array.<UnistNode>|undefined} */
     let replacement
-    /** @type {boolean} */
+    /** @type {boolean|undefined} */
     let change
 
     if (node.type === 'text') {
@@ -239,7 +238,7 @@ export function toNlcst(tree, file, Parser) {
       }
     }
 
-    return change
+    return change && replacement
       ? patch(replacement, location, location.toOffset(pointStart(node)))
       : replacement
   }
@@ -256,7 +255,7 @@ export function toNlcst(tree, file, Parser) {
     let index = -1
 
     while (++index < children.length) {
-      push.apply(results, one(children[index]) || [])
+      results.push(...(one(children[index]) || []))
     }
 
     return results
@@ -306,13 +305,13 @@ export function toNlcst(tree, file, Parser) {
  * @returns {boolean}
  */
 function dataNlcstSourced(node) {
-  return node.properties.dataNlcst === 'source'
+  return Boolean(node.properties && node.properties.dataNlcst === 'source')
 }
 
 /**
  * @param {Element} node
  * @returns {boolean}
  */
 function dataNlcstIgnore(node) {
-  return node.properties.dataNlcst === 'ignore'
+  return Boolean(node.properties && node.properties.dataNlcst === 'ignore')
 }

test/index.js

@@ -3,8 +3,11 @@ import path from 'path'
 import test from 'tape'
 import rehype from 'rehype'
 import vfile from 'vfile'
+// @ts-expect-error: to do type.
 import {ParseLatin} from 'parse-latin'
+// @ts-expect-error: to do type.
 import {ParseDutch} from 'parse-dutch'
+// @ts-expect-error: to do type.
 import {ParseEnglish} from 'parse-english'
 import {isHidden} from 'is-hidden'
 import {toNlcst} from '../index.js'

tsconfig.json

@@ -10,6 +10,7 @@
     "declaration": true,
     "emitDeclarationOnly": true,
     "allowSyntheticDefaultImports": true,
-    "skipLibCheck": true
+    "skipLibCheck": true,
+    "strict": true
   }
 }