Enable strict typescript

.eslintrc.js

@@ -41,6 +41,7 @@ module.exports = {
     '@typescript-eslint/no-explicit-any': 'error',
     '@typescript-eslint/no-floating-promises': 'error',
     '@typescript-eslint/no-misused-new': 'error',
+    '@typescript-eslint/no-non-null-assertion': 'off',
     '@typescript-eslint/no-unnecessary-qualifier': 'error',
     '@typescript-eslint/no-unnecessary-type-assertion': 'error',
     '@typescript-eslint/no-unused-expressions': [
@@ -94,6 +95,7 @@ module.exports = {
     'no-caller': 'error',
     'no-case-declarations': 'off',
     'no-cond-assign': 'error',
+    'no-console': 'error',
     'no-constant-condition': 'error',
     'no-control-regex': 'error',
     'no-duplicate-imports': 'error',

jest.config.js

@@ -2,4 +2,5 @@
 module.exports = {
   preset: 'ts-jest',
   testEnvironment: 'node',
+  testRegex: '(\\.|/)(test|spec)\\.(j|t)s(x?)$',
 }

package.json

@@ -27,9 +27,11 @@
     "lint": "yarn eslint . --fix --config .eslintrc.js",
     "format": "yarn prettier --write .",
     "format-check": "yarn prettier --check .",
+    "typecheck": "tsc --noEmit",
+    "typecheck:watch": "tsc --noEmit --watch",
     "run-ts": "TS_NODE_PROJECT=tsconfig.json node --loader ts-node/esm",
-    "test": "jest **/*.test.ts",
-    "test-ci": "yarn run-ts ./node_modules/.bin/nyc jest **/*.test.ts"
+    "test": "jest",
+    "test-ci": "yarn run-ts ./node_modules/.bin/nyc jest"
   },
   "nyc": {
     "extension": [

src/cache.ts

@@ -44,6 +44,7 @@ export class Cache {
     if (what === 'all') {
       this.all = value as Date[]
     } else {
+      args = args || {}
       args._value = value
       this[what].push(args as IterArgs)
     }
@@ -65,7 +66,7 @@ export class Cache {
     const findCacheDiff = function (item: IterArgs) {
       for (let i = 0; i < argsKeys.length; i++) {
         const key = argsKeys[i]
-        if (!argsMatch(args[key], item[key])) {
+        if (!argsMatch(args?.[key], item[key])) {
           return true
         }
       }
@@ -89,7 +90,7 @@ export class Cache {
     if (!cached && this.all) {
       // Not in the cache, but we already know all the occurrences,
       // so we can find the correct dates from the cached ones.
-      const iterResult = new IterResult(what, args)
+      const iterResult = new IterResult(what, args ?? {})
       for (let i = 0; i < (this.all as Date[]).length; i++) {
         if (!iterResult.accept((this.all as Date[])[i])) break
       }

src/dateutil.ts

@@ -211,7 +211,7 @@ const dateTZtoISO8601 = function (date: Date, timeZone: string) {
   return dateStr.replace(' ', 'T') + 'Z'
 }
 
-export const dateInTimeZone = function (date: Date, timeZone: string) {
+export const dateInTimeZone = function (date: Date, timeZone?: string) {
   const localTimeZone = Intl.DateTimeFormat().resolvedOptions().timeZone
   // Date constructor can only reliably parse dates in ISO8601 format
   const dateInLocalTZ = new Date(dateTZtoISO8601(date, localTimeZone))

src/datewithzone.ts

@@ -30,7 +30,7 @@ export class DateWithZone {
   }
 
   public rezonedDate() {
-    if (this.isUTC) {
+    if (this.isUTC || !this.tzid) {
       return this.date
     }
 

src/iter/index.ts

@@ -67,8 +67,7 @@ export function iter<M extends QueryMethodTypes>(
         }
 
         const date = fromOrdinal(ii.yearordinal + currentDay)
-        for (let k = 0; k < timeset.length; k++) {
-          const time = timeset[k]
+        for (const time of timeset) {
           const res = combine(date, time)
           if (until && res > until) {
             return emitResult(iterResult)
@@ -131,7 +130,7 @@ function isFiltered(
 
   return (
     (notEmpty(bymonth) && !includes(bymonth, ii.mmask[currentDay])) ||
-    (notEmpty(byweekno) && !ii.wnomask[currentDay]) ||
+    (notEmpty(byweekno) && !ii.wnomask?.[currentDay]) ||
     (notEmpty(byweekday) && !includes(byweekday, ii.wdaymask[currentDay])) ||
     (notEmpty(ii.nwdaymask) && !ii.nwdaymask[currentDay]) ||
     (byeaster !== null && !includes(ii.eastermask, currentDay)) ||
@@ -167,9 +166,11 @@ function removeFilteredDays(
   for (let dayCounter = start; dayCounter < end; dayCounter++) {
     const currentDay = dayset[dayCounter]
 
-    filtered = isFiltered(ii, currentDay, options)
+    if (currentDay !== null) {
+      filtered = isFiltered(ii, currentDay, options)
 
-    if (filtered) dayset[currentDay] = null
+      if (filtered) dayset[currentDay] = null
+    }
   }
 
   return filtered
@@ -179,7 +180,7 @@ function makeTimeset(
   ii: Iterinfo,
   counterDate: DateTime,
   options: ParsedOptions
-): Time[] | null {
+): Time[] {
   const { freq, byhour, byminute, bysecond } = options
 
   if (freqIsDailyOrGreater(freq)) {

src/iterinfo/index.ts

@@ -14,9 +14,9 @@ export type GetDayset = () => DaySet
 // =============================================================================
 
 export default class Iterinfo {
-  public yearinfo: YearInfo
-  public monthinfo: MonthInfo
-  public eastermask: number[] | null
+  public yearinfo!: YearInfo
+  public monthinfo!: MonthInfo
+  public eastermask!: number[]
 
   // eslint-disable-next-line no-empty-function
   constructor(private options: ParsedOptions) {}
@@ -32,7 +32,7 @@ export default class Iterinfo {
       notEmpty(options.bynweekday) &&
       (month !== this.lastmonth || year !== this.lastyear)
     ) {
-      const { yearlen, mrange, wdaymask } = this.yearinfo
+      const { yearlen, mrange, wdaymask } = this.yearinfo ?? {}
       this.monthinfo = rebuildMonth(
         year,
         month,
@@ -153,15 +153,20 @@ export default class Iterinfo {
   getdayset(freq: Frequency): (y: number, m: number, d: number) => DaySet {
     switch (freq) {
       case Frequency.YEARLY:
-        return this.ydayset.bind(this)
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        return this.ydayset.bind(this) as any
       case Frequency.MONTHLY:
-        return this.mdayset.bind(this)
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        return this.mdayset.bind(this) as any
       case Frequency.WEEKLY:
-        return this.wdayset.bind(this)
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        return this.wdayset.bind(this) as any
       case Frequency.DAILY:
-        return this.ddayset.bind(this)
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        return this.ddayset.bind(this) as any
       default:
-        return this.ddayset.bind(this)
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        return this.ddayset.bind(this) as any
     }
   }
 

src/iterinfo/monthinfo.ts

@@ -49,9 +49,8 @@ export function rebuildMonth(
     const first = rang[0]
     const last = rang[1] - 1
 
-    for (let k = 0; k < options.bynweekday.length; k++) {
+    for (const [wday, n] of options.bynweekday ?? []) {
       let i
-      const [wday, n] = options.bynweekday[k]
       if (n < 0) {
         i = last + (n + 1) * 7
         i -= pymod(wdaymask[i] - wday, 7)

src/iterresult.ts

@@ -29,13 +29,15 @@ export default class IterResult<M extends QueryMethodTypes> {
 
     if (method === 'between') {
       this.maxDate = args.inc
-        ? args.before
-        : new Date(args.before.getTime() - 1)
-      this.minDate = args.inc ? args.after : new Date(args.after.getTime() + 1)
+        ? args.before!
+        : new Date(args.before!.getTime() - 1)
+      this.minDate = args.inc
+        ? args.after!
+        : new Date(args.after!.getTime() + 1)
     } else if (method === 'before') {
-      this.maxDate = args.inc ? args.dt : new Date(args.dt.getTime() - 1)
+      this.maxDate = args.inc ? args.dt! : new Date(args.dt!.getTime() - 1)
     } else if (method === 'after') {
-      this.minDate = args.inc ? args.dt : new Date(args.dt.getTime() + 1)
+      this.minDate = args.inc ? args.dt! : new Date(args.dt!.getTime() + 1)
     }
   }
 

src/iterset.ts

@@ -43,7 +43,7 @@ export function iterSet<M extends QueryMethodTypes>(
   }
 
   if (iterResult.method === 'between') {
-    evalExdate(iterResult.args.after, iterResult.args.before)
+    evalExdate(iterResult.args.after!, iterResult.args.before!)
     iterResult.accept = function (date) {
       const dt = Number(date)
       if (!_exdateHash[dt]) {

src/nlp/parsetext.ts

@@ -9,9 +9,9 @@ import { WeekdayStr } from '../weekday'
 
 class Parser {
   private readonly rules: { [k: string]: RegExp }
-  public text: string
-  public symbol: string | null
-  public value: RegExpExecArray | null
+  public text!: string
+  public symbol!: string | null
+  public value!: RegExpExecArray | null
   private done = true
 
   constructor(rules: { [k: string]: RegExp }) {
@@ -30,7 +30,7 @@ class Parser {
 
   nextSymbol() {
     let best: RegExpExecArray | null
-    let bestSymbol: string
+    let bestSymbol = ''
 
     this.symbol = null
     this.value = null
@@ -390,7 +390,7 @@ export default function parseText(text: string, language: Language = ENGLISH) {
         ttr.nextSymbol()
         return ttr.accept('last') ? -3 : 3
       case 'nth':
-        const v = parseInt(ttr.value[1], 10)
+        const v = parseInt(ttr.value![1], 10)
         if (v < -366 || v > 366) throw new Error('Nth out of range: ' + v)
 
         ttr.nextSymbol()
@@ -431,7 +431,7 @@ export default function parseText(text: string, language: Language = ENGLISH) {
       if (!date) throw new Error('Cannot parse until date:' + ttr.text)
       options.until = new Date(date)
     } else if (ttr.accept('for')) {
-      options.count = parseInt(ttr.value[0], 10)
+      options.count = parseInt(ttr.value![0], 10)
       ttr.expect('number')
       // ttr.expect('times')
     }