Option to disable last day of month in arrayToString

src/index.ts

@@ -6,17 +6,17 @@ import { units } from "./units.js";
 export { Schedule } from "./schedule.js";
 export { Unit, Options } from "./types.js";
 
+const defaultParseOptions: ParseOptions = {
+  enableLastDayOfMonth: true,
+};
+
 const defaultOptions: Options = {
+  ...defaultParseOptions,
   outputHashes: false,
   outputMonthNames: false,
   outputWeekdayNames: false,
 };
 
-
-const defaultParseOptions: ParseOptions = {
-  enableLastDayOfMonth: true
-};
-
 /**
  * Parses a cron string
  *
@@ -32,9 +32,11 @@ export function stringToArray(str: string, options?: Partial<ParseOptions>) {
   if (parts.length !== 5) {
     throw new Error("Invalid cron string format");
   } else {
-    return parts.map((str, idx) => stringToArrayPart(str, units[idx], { ...defaultParseOptions, ...options }));
+    return parts.map((str, idx) =>
+      stringToArrayPart(str, units[idx], { ...defaultParseOptions, ...options })
+    );
   }
-};
+}
 
 /**
  * Parses a 2-dimentional array of integers and serializes it to a string

src/part.ts

@@ -18,7 +18,7 @@ export const arrayToStringPart = (
     dedup(
       fixSunday(
         arr.map((value) => {
-          const parsedValue = parseNumber(unit, value, {enableLastDayOfMonth: false});
+          const parsedValue = parseNumber(unit, value, options);
           if (parsedValue === undefined) {
             throw getError(`Invalid value "${value}"`, unit);
           }
@@ -31,7 +31,7 @@ export const arrayToStringPart = (
   if (!values.length) {
     throw getError("Empty interval value", unit);
   }
-  assertInRange(values, unit);
+  assertInRange(values, unit, options);
   return toString(values, unit, options);
 };
 
@@ -40,10 +40,14 @@ export const arrayToStringPart = (
  *
  * @param str The part of a cron string to convert
  * @param unit The unit for the part
- * @param options Parse options
+ * @param options The parse options
  * @return An array of numbers
  */
-export const stringToArrayPart = (str: string, unit: Unit, options: ParseOptions) => {
+export const stringToArrayPart = (
+  str: string,
+  unit: Unit,
+  options: ParseOptions
+) => {
   const values = sort(
     dedup(
       fixSunday(
@@ -71,7 +75,7 @@ export const stringToArrayPart = (str: string, unit: Unit, options: ParseOptions
       )
     )
   );
-  assertInRange(values, unit);
+  assertInRange(values, unit, options);
   return values;
 };
 
@@ -105,7 +109,7 @@ const toRanges = (values: number[]) => {
  *
  * @param values An array of numbers
  * @param unit The unit for the part
- * @param options The formatting options to use
+ * @param options The options to use
  * @return The part of a cron string
  */
 const toString = (values: number[], unit: Unit, options: Options) => {
@@ -116,8 +120,8 @@ const toString = (values: number[], unit: Unit, options: Options) => {
     } else {
       retval = "*";
     }
-  } else if (unit.name === 'day' && values.length === 1 && values[0] === -1) {
-    retval = 'L';
+  } else if (unit.name === "day" && values.length === 1 && values[0] === -1) {
+    retval = "L";
   } else {
     const step = getStep(values);
     if (step && isInterval(values, step)) {
@@ -199,7 +203,12 @@ const getError = (error: string, unit: Unit) =>
  * @param options Parse options
  * @return The resulting array
  */
-const parseRange = (rangeString: string, context: string, unit: Unit, options: ParseOptions) => {
+const parseRange = (
+  rangeString: string,
+  context: string,
+  unit: Unit,
+  options: ParseOptions
+) => {
   const subparts = rangeString.split("-");
   if (subparts.length === 1) {
     const value = parseNumber(unit, subparts[0], options);
@@ -302,11 +311,12 @@ const replaceAlternatives = (str: string, unit: Unit) => {
  *
  * @param values The values to test
  * @param unit The unit for the part
+ * @param options The parse options
  */
-const assertInRange = (values: number[], unit: Unit) => {
+const assertInRange = (values: number[], unit: Unit, options: ParseOptions) => {
   let first = values[0];
   let last = values[values.length - 1];
-  if (unit.name === 'day' && first === -1 && last === -1) {
+  if (options.enableLastDayOfMonth && unit.name === "day" && first === -1 && last === -1) {
     first = Math.abs(first);
     last = Math.abs(last);
   }

src/types.ts

@@ -3,14 +3,14 @@ export type Unit = {
   min: number;
   max: number;
   alt?: ReadonlyArray<string>;
-}
+};
 
-export type Options = {
+export type ParseOptions = {
+  enableLastDayOfMonth: boolean;
+};
+
+export type Options = ParseOptions & {
   outputHashes: boolean;
   outputWeekdayNames: boolean;
   outputMonthNames: boolean;
-}
-
-export type ParseOptions = {
-  enableLastDayOfMonth: boolean;
-}
+};

test/cron.invalid.array.ts

@@ -1,7 +1,13 @@
 import { expect } from "chai";
 import { arrayToString } from "../src/index.js";
 
-const invalidCron = [
+type Test = {
+  array: number[][];
+  error: string;
+  enableLastDayOfMonth?: boolean;
+};
+
+const invalidCron: Test[] = [
   {
     array: [],
     error: "Invalid cron array",
@@ -38,12 +44,21 @@ const invalidCron = [
     array: [[1], [1], [-2], [1], [1]],
     error: 'Value "-2" out of range for day',
   },
+  {
+    array: [[1], [1], [-1], [1], [1]],
+    error: 'Value "-1" out of range for day',
+    enableLastDayOfMonth: false,
+  },
 ];
 
 describe("Should throw on invalid cron array", function () {
   invalidCron.forEach(function (invalid) {
     it(invalid.array.toString(), function () {
-      expect(() => arrayToString(invalid.array)).to.throw(invalid.error);
+      expect(() =>
+        arrayToString(invalid.array, {
+          enableLastDayOfMonth: invalid.enableLastDayOfMonth,
+        })
+      ).to.throw(invalid.error);
     });
   });
 });

test/cron.invalid.string.ts

@@ -70,12 +70,18 @@ const invalidCron = [
     string: "5/ * * * *",
     error: 'Invalid interval step value "" for minute',
   },
+  {
+    string: "* * L * *",
+    error: 'Invalid value "L" for day',
+  },
 ];
 
 describe("Should throw on invalid cron string", function () {
   invalidCron.forEach(function (invalid) {
     it(`${invalid.string}`, function () {
-      expect(() => stringToArray(invalid.string)).to.throw(invalid.error);
+      expect(() =>
+        stringToArray(invalid.string, { enableLastDayOfMonth: false })
+      ).to.throw(invalid.error);
     });
   });
 });

test/range.valid.ts

@@ -105,6 +105,7 @@ describe("Should parse valid string", function () {
     it(validRange.input + " as string", function () {
       expect(
         arrayToStringPart(range, validRange.unit, {
+          enableLastDayOfMonth: true,
           outputHashes: false,
           outputMonthNames: false,
           outputWeekdayNames: false,