fix(formula): leftb byte length

dream-num · Sep 13, 2024 · 5530361 · 5530361
1 parent bf5cd9c
commit 5530361
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Showing 2 changed files with 92 additions and 16 deletions.
diff --git a/packages/engine-formula/src/functions/text/leftb/__test__/index.spec.ts b/packages/engine-formula/src/functions/text/leftb/__test__/index.spec.ts
@@ -16,16 +16,16 @@
 
 import { describe, expect, it } from 'vitest';
 
+import { ErrorType } from '../../../../basics/error-type';
+import { ArrayValueObject, transformToValue, transformToValueObject } from '../../../../engine/value-object/array-value-object';
+import { NumberValueObject, StringValueObject } from '../../../../engine/value-object/primitive-object';
 import { FUNCTION_NAMES_TEXT } from '../../function-names';
 import { Leftb } from '../index';
-import { NumberValueObject, StringValueObject } from '../../../../engine/value-object/primitive-object';
-import { ArrayValueObject, transformToValue, transformToValueObject } from '../../../../engine/value-object/array-value-object';
-import { ErrorType } from '../../../../basics/error-type';
 
-describe('Test LEFT function', () => {
+describe('Test LEFTB function', () => {
     const leftbFunction = new Leftb(FUNCTION_NAMES_TEXT.LEFTB);
 
-    describe('Left', () => {
+    describe('Leftb', () => {
         describe('Single Value Tests', () => {
             it('Should return leftmost bytes of a single text', () => {
                 const text = StringValueObject.create('Hello World');
@@ -161,5 +161,72 @@ describe('Test LEFT function', () => {
             const result = leftbFunction.calculate(text, numChars);
             expect(transformToValue(result.getArrayValue())).toStrictEqual([['']]);
         });
+
+        it('Handles extracting CJK, first byte', () => {
+            const textArray = new ArrayValueObject({
+                calculateValueList: transformToValueObject([
+                    ['销售额'],
+                    ['から'],
+                    ['이트'],
+                ]),
+                rowCount: 3,
+                columnCount: 1,
+                unitId: '',
+                sheetId: '',
+                row: 0,
+                column: 0,
+            });
+            const result = leftbFunction.calculate(textArray);
+            expect(transformToValue(result.getArrayValue())).toStrictEqual([
+                [''],
+                [''],
+                [''],
+            ]);
+        });
+
+        it('Handles extracting CJK, first character', () => {
+            const textArray = new ArrayValueObject({
+                calculateValueList: transformToValueObject([
+                    ['销售额'],
+                    ['から'],
+                    ['이트'],
+                ]),
+                rowCount: 3,
+                columnCount: 1,
+                unitId: '',
+                sheetId: '',
+                row: 0,
+                column: 0,
+            });
+            const result = leftbFunction.calculate(textArray, NumberValueObject.create(2));
+            expect(transformToValue(result.getArrayValue())).toStrictEqual([
+                ['销'],
+                ['か'],
+                ['이'],
+            ]);
+        });
+        it('Handles extracting multiple languages', () => {
+            const textArray = new ArrayValueObject({
+                calculateValueList: transformToValueObject([
+                    ['销售额'],
+                    ['uから'],
+                    ['이u트'],
+                    ['이트u'],
+                ]),
+                rowCount: 4,
+                columnCount: 1,
+                unitId: '',
+                sheetId: '',
+                row: 0,
+                column: 0,
+            });
+            const result = leftbFunction.calculate(textArray, NumberValueObject.create(3));
+            expect(transformToValue(result.getArrayValue())).toStrictEqual([
+                ['销'],
+                ['uか'],
+                ['이u'],
+                ['이'],
+            ]);
+        });
     });
 });
diff --git a/packages/engine-formula/src/functions/text/leftb/index.ts b/packages/engine-formula/src/functions/text/leftb/index.ts
@@ -16,11 +16,11 @@
 
 import { ErrorType } from '../../../basics/error-type';
 import { expandArrayValueObject } from '../../../engine/utils/array-object';
+import { charLenByte } from '../../../engine/utils/char-kit';
 import { ArrayValueObject } from '../../../engine/value-object/array-value-object';
-import type { BaseValueObject } from '../../../engine/value-object/base-value-object';
 import { NumberValueObject, StringValueObject } from '../../../engine/value-object/primitive-object';
 import { BaseFunction } from '../../base-function';
-import { charLenByte } from '../../../engine/utils/char-kit';
+import type { BaseValueObject } from '../../../engine/value-object/base-value-object';
 
 export class Leftb extends BaseFunction {
     override minParams = 1;
@@ -68,11 +68,7 @@ export class Leftb extends BaseFunction {
                 }
 
                 const textValueString = `${textValue.getValue()}`;
-                const byteLength = charLenByte(textValueString);
-                if (numBytesValueNumber >= byteLength) {
-                    return ArrayValueObject.createByArray([[textValueString]]); // Return original string if numBytes >= byteLength
-                }
-                return StringValueObject.create(Array.from(textValueString).slice(0, numBytesValueNumber).join(''));
+                return StringValueObject.create(this._sliceByBytes(textValueString, numBytesValueNumber));
             });
         }
 
@@ -90,12 +86,25 @@ export class Leftb extends BaseFunction {
         if (typeof numBytesValueNumber !== 'number' || numBytesValueNumber < 0) {
             return ArrayValueObject.createByArray([[ErrorType.VALUE]]);
         }
-        const byteLength = charLenByte(textValueString);
 
-        if (numBytesValueNumber >= byteLength) {
-            return ArrayValueObject.createByArray([[textValueString]]); // Return original string if numBytes >= byteLength
+        return ArrayValueObject.createByArray([[this._sliceByBytes(textValueString, numBytesValueNumber)]]);
+    }
+
+    private _sliceByBytes(text: string, numBytes: number) {
+        let byteCount = 0;
+        let sliceIndex = 0;
+
+        // Iterate over each Unicode character (correctly handling multi-byte characters and emoji)
+        for (let i = 0; i < text.length; i++) {
+            const char = text[i];
+            const charByteLength = charLenByte(char);
+            if (byteCount + charByteLength > numBytes) {
+                break;
+            }
+            byteCount += charByteLength;
+            sliceIndex++;
         }
 
-        return ArrayValueObject.createByArray([[Array.from(textValueString).slice(0, numBytesValueNumber).join('')]]);
+        return [...text].slice(0, sliceIndex).join('');
     }
 }