From fefdcff14f5579727ae3aeb24400f728b25029af Mon Sep 17 00:00:00 2001
From: Nikita Barsukov <nikita.s.barsukov@gmail.com>
Date: Tue, 3 Dec 2024 19:01:44 +0300
Subject: [PATCH] fix(legacy): `InputNumber` has bad support of dynamic postfix
 (#9899)

---
 .../tests/input-number/dynamic-postfix.cy.ts  | 126 ++++++++++++++++++
 .../input-number/input-number.component.ts    |   9 ++
 2 files changed, 135 insertions(+)
 create mode 100644 projects/demo-cypress/src/tests/input-number/dynamic-postfix.cy.ts

diff --git a/projects/demo-cypress/src/tests/input-number/dynamic-postfix.cy.ts b/projects/demo-cypress/src/tests/input-number/dynamic-postfix.cy.ts
new file mode 100644
index 000000000000..09e1237d9b1d
--- /dev/null
+++ b/projects/demo-cypress/src/tests/input-number/dynamic-postfix.cy.ts
@@ -0,0 +1,126 @@
+import '@angular/common/locales/global/ru';
+
+import {I18nPluralPipe} from '@angular/common';
+import {ChangeDetectionStrategy, Component} from '@angular/core';
+import {FormsModule} from '@angular/forms';
+import {TuiRoot} from '@taiga-ui/core';
+import {TuiInputNumberModule, TuiTextfieldControllerModule} from '@taiga-ui/legacy';
+
+@Component({
+    standalone: true,
+    imports: [
+        FormsModule,
+        I18nPluralPipe,
+        TuiInputNumberModule,
+        TuiRoot,
+        TuiTextfieldControllerModule,
+    ],
+    template: `
+        <tui-root>
+            <tui-input-number
+                [tuiTextfieldPostfix]="value | i18nPlural: pluralMap : 'ru-RU'"
+                [(ngModel)]="value"
+            ></tui-input-number>
+        </tui-root>
+    `,
+    changeDetection: ChangeDetectionStrategy.OnPush,
+})
+export class TestInputNumberWithPostfix {
+    protected value: number | null = null;
+    protected pluralMap = {
+        one: 'секунда',
+        few: 'секунды',
+        many: 'секунд',
+        other: 'секунды',
+    };
+}
+
+describe('InputNumber with dynamic postfix', () => {
+    describe('Plural forms of seconds (locale ru-RU)', () => {
+        beforeEach(() => {
+            cy.mount(TestInputNumberWithPostfix);
+            cy.get('tui-input-number input').as('textfield');
+        });
+
+        const withPostfix = (
+            range: number[],
+            postfix: string,
+        ): ReadonlyArray<{typed: string; value: string}> =>
+            range.map(String).map((x) => ({typed: x, value: `${x} ${postfix}`}));
+
+        (
+            [
+                {typed: '1', value: '1 секунда'},
+                ...withPostfix(range(2, 4), 'секунды'),
+                ...withPostfix(range(5, 20), 'секунд'),
+                {typed: '21', value: '21 секунда'},
+                ...withPostfix(range(22, 24), 'секунды'),
+                ...withPostfix(range(25, 30), 'секунд'),
+                {typed: '31', value: '31 секунда'},
+            ] as const
+        ).forEach(({typed, value}) => {
+            it(`Type ${typed} => ${value}`, () => {
+                cy.get('@textfield').type(typed);
+
+                cy.get('@textfield')
+                    .should('have.value', value)
+                    .should('have.prop', 'selectionStart', typed.length)
+                    .should('have.prop', 'selectionEnd', typed.length);
+            });
+        });
+
+        it('Press sequentially 123', () => {
+            cy.get('@textfield')
+                .type('1')
+                .should('have.value', '1 секунда')
+                .should('have.prop', 'selectionStart', 1)
+                .should('have.prop', 'selectionEnd', 1)
+                .type('2')
+                .should('have.value', '12 секунд')
+                .should('have.prop', 'selectionStart', 2)
+                .should('have.prop', 'selectionEnd', 2)
+                .type('3')
+                .should('have.value', '123 секунды')
+                .should('have.prop', 'selectionStart', 3)
+                .should('have.prop', 'selectionEnd', 3);
+        });
+
+        it('12|3 секунды => Backspace => 1|3 секунд', () => {
+            cy.get('@textfield')
+                .type('123')
+                .should('have.value', '123 секунды')
+                .type('{leftArrow}')
+                .should('have.prop', 'selectionStart', 2)
+                .should('have.prop', 'selectionEnd', 2)
+                .type('{backspace}')
+                .should('have.value', '13 секунд')
+                .should('have.prop', 'selectionStart', 1)
+                .should('have.prop', 'selectionEnd', 1);
+        });
+
+        it('1|3 секунды => Delete => 1| секунда', () => {
+            cy.get('@textfield')
+                .type('13')
+                .type('{leftArrow}')
+                .should('have.value', '13 секунд')
+                .should('have.prop', 'selectionStart', 1)
+                .should('have.prop', 'selectionEnd', 1)
+                .type('{del}')
+                .should('have.value', '1 секунда')
+                .should('have.prop', 'selectionStart', 1)
+                .should('have.prop', 'selectionEnd', 1);
+        });
+
+        it('1| секунда => Backspace => Empty textfield', () => {
+            cy.get('@textfield')
+                .type('1')
+                .should('have.value', '1 секунда')
+                .type('{backspace}')
+                .should('have.value', '');
+        });
+    });
+});
+
+export function range(from: number, to: number): number[] {
+    return new Array(to - from + 1).fill(null).map((_, i) => from + i);
+}
diff --git a/projects/legacy/components/input-number/input-number.component.ts b/projects/legacy/components/input-number/input-number.component.ts
index df6888c60872..4eb1eefd2625 100644
--- a/projects/legacy/components/input-number/input-number.component.ts
+++ b/projects/legacy/components/input-number/input-number.component.ts
@@ -9,6 +9,7 @@ import {
 } from '@angular/core';
 import {takeUntilDestroyed} from '@angular/core/rxjs-interop';
 import type {MaskitoOptions} from '@maskito/core';
+import {maskitoInitialCalibrationPlugin} from '@maskito/core';
 import {
     maskitoCaretGuard,
     maskitoNumberOptionsGenerator,
@@ -336,11 +337,19 @@ export class TuiInputNumberComponent
             decimalZeroPadding: decimalMode === 'always',
         };
         const {plugins, ...options} = maskitoNumberOptionsGenerator(generatorParams);
+        const initialCalibrationPlugin = maskitoInitialCalibrationPlugin(
+            maskitoNumberOptionsGenerator({
+                ...generatorParams,
+                min: Number.MIN_SAFE_INTEGER,
+                max: Number.MAX_SAFE_INTEGER,
+            }),
+        );
 
         return {
             ...options,
             plugins: [
                 ...plugins,
+                initialCalibrationPlugin,
                 maskitoCaretGuard((value) => [
                     prefix.length,
                     value.length - postfix.length,