Add option to trim leading zeros in hours description

README.md

@@ -128,6 +128,7 @@ An options object can be passed as the second parameter to `cronstrue.toString`.
 - **dayOfWeekStartIndexZero: boolean** - Whether to interpret cron expression DOW `1` as Sunday or Monday. (Default: true)
 - **monthStartIndexZero: boolean** - Whether to interpret January as `0` or `1`. (Default: false)
 - **use24HourTimeFormat: boolean** - If true, descriptions will use a [24-hour clock](https://en.wikipedia.org/wiki/24-hour_clock) (Default: false but some translations will default to true)
+- **trimHoursLeadingZero: boolean** - Whether to trim the leading zero that may appear in the hours description; e.g. "02:00 AM" -> "2:00 AM", "08:00" -> "8:00" (Default: false)
 - **locale: string** - The locale to use (Default: "en")
 - **logicalAndDayFields: boolean** - If true, descriptions for cron expressions with both day of month and day of week specified will follow a logical-AND wording rather than logical-OR wording; e.g. "...between day 11 and 17 of the month, only on Friday" rather than "...between day 11 and 17 of the month, and on Friday" (Default: false)
 

src/expressionDescriptor.ts

@@ -26,6 +26,7 @@ export class ExpressionDescriptor {
    *         dayOfWeekStartIndexZero = true,
    *         monthStartIndexZero = false,
    *         use24HourTimeFormat = false,
+   *         trimHoursLeadingZero = false,
    *         locale = 'en'
    *     }={}]
    * @returns {string}
@@ -38,6 +39,7 @@ export class ExpressionDescriptor {
       dayOfWeekStartIndexZero = true,
       monthStartIndexZero = false,
       use24HourTimeFormat,
+      trimHoursLeadingZero = false,
       locale = null,
       logicalAndDayFields = false,
     }: Options = {}
@@ -51,6 +53,7 @@ export class ExpressionDescriptor {
       dayOfWeekStartIndexZero: dayOfWeekStartIndexZero,
       monthStartIndexZero: monthStartIndexZero,
       use24HourTimeFormat: use24HourTimeFormat,
+      trimHoursLeadingZero: trimHoursLeadingZero,
       locale: locale,
       logicalAndDayFields: logicalAndDayFields,
     };
@@ -706,9 +709,15 @@ export class ExpressionDescriptor {
       second = `:${("00" + secondExpression).substring(secondExpression.length)}`;
     }
 
-    return `${setPeriodBeforeTime ? period : ""}${("00" + hour.toString()).substring(hour.toString().length)}:${(
-      "00" + minute.toString()
-    ).substring(minute.toString().length)}${second}${!setPeriodBeforeTime ? period : ""}`;
+    const hourStr = hour.toString();
+    const paddedHour = ("00" + hourStr).substring(hourStr.length);
+    const minuteStr = minute.toString();
+    const paddedMinute = ("00" + minuteStr).substring(minuteStr.length);
+    const displayHour = this.options.trimHoursLeadingZero ? hourStr : paddedHour;
+
+    return `${setPeriodBeforeTime ? period : ""}${displayHour}:${paddedMinute}${second}${
+      !setPeriodBeforeTime ? period : ""
+    }`;
   }
 
   protected transformVerbosity(description: string, useVerboseFormat: boolean) {

src/options.ts

@@ -4,6 +4,7 @@ export interface Options {
   dayOfWeekStartIndexZero?: boolean;
   monthStartIndexZero?: boolean;
   use24HourTimeFormat?: boolean;
+  trimHoursLeadingZero?: boolean;
   locale?: string | null;
   /**
    * The day of month and day of week are logical AND'ed (as opposed to OR'ed).

test/cronstrue.ts

@@ -188,6 +188,35 @@ describe("Cronstrue", function () {
       assert.equal(cronstrue.toString(this.test?.title as string), "At 03:30 AM");
     });
 
+    it("30 10 * * *", function () {
+      assert.equal(cronstrue.toString(this.test?.title as string, { trimHoursLeadingZero: true }), "At 10:30 AM");
+    });
+
+    it("31 10 * * *", function () {
+      assert.equal(
+        cronstrue.toString(this.test?.title as string, { trimHoursLeadingZero: true, use24HourTimeFormat: true }),
+        "At 10:31"
+      );
+    });
+
+    it("29 9 * * *", function () {
+      assert.equal(cronstrue.toString(this.test?.title as string, { trimHoursLeadingZero: true }), "At 9:29 AM");
+    });
+
+    it("30 9 * * *", function () {
+      assert.equal(
+        cronstrue.toString(this.test?.title as string, { trimHoursLeadingZero: true, use24HourTimeFormat: true }),
+        "At 9:30"
+      );
+    });
+
+    it("0 0 * * *", function () {
+      assert.equal(
+        cronstrue.toString(this.test?.title as string, { trimHoursLeadingZero: true, use24HourTimeFormat: true }),
+        "At 0:00"
+      );
+    });
+
     it("10 11 * * *", function () {
       assert.equal(cronstrue.toString(this.test?.title as string, { verbose: true }), "At 11:10 AM, every day");
     });

test/i18n.ts

@@ -1,7 +1,6 @@
 import "mocha";
 import cronstrue from "../src/cronstrue-i18n";
-import chai = require("chai");
-let assert = chai.assert;
+import { assert } from "chai";
 
 describe("i18n", function () {
   describe("de", function () {