add test

Fix issue 4167

CHANGELOG.md

@@ -37,6 +37,8 @@
 * 【core   】      修复`DateModifier`处理AM和PM的ceiling和round问题（pr#4161@Github）
 * 【poi    】      修复`Word07Writer`run.setColor()的颜色十六进制转换逻辑（pr#4164@Github）
 * 【core   】      修复`Arrangement.iterate(int m)`方法的排列迭代器实现逻辑问题（pr#4166@Github）
+* 【core   】      修复`HexUtil.format`在处理长度小于2的字符串会抛异常，在处理长度为奇数的字符串时最后一个字符会被忽略的问题（pr#4168@Github）
+* 【core   】      修复`SplitIter.computeNext`递归调用可能导致栈溢出风险（pr#4168@Github）
 
 -------------------------------------------------------------------------------------------------------------
 # 5.8.41(2025-10-12)

hutool-core/src/main/java/cn/hutool/core/text/csv/CsvParser.java

@@ -114,7 +114,7 @@ public final class CsvParser extends ComputeIter<CsvRow> implements Closeable, S
 	/**
 	 * 读取下一行数据
 	 *
-	 * @return CsvRow，{@code null}表示
+	 * @return CsvRow，{@code null}表示读取结束
 	 * @throws IORuntimeException IO读取异常
 	 */
 	public CsvRow nextRow() throws IORuntimeException {

hutool-core/src/main/java/cn/hutool/core/text/split/SplitIter.java

@@ -71,29 +71,28 @@ public class SplitIter extends ComputeIter<String> implements Serializable {
 			return text.substring(offset);
 		}
 
-		final int start = finder.start(offset);
+		String result = null;
-		// 无分隔符，结束
+		int start;
-		if (start < 0) {
+		do {
-			// 如果不再有分隔符，但是遗留了字符，则单独作为一个段
+			start = finder.start(offset);
-			if (offset <= text.length()) {
+			// 无分隔符，结束
-				final String result = text.substring(offset);
+			if (start < 0) {
-				if (false == ignoreEmpty || false == result.isEmpty()) {
+				// 如果不再有分隔符，但是遗留了字符，则单独作为一个段
-					// 返回非空串
+				if (offset <= text.length()) {
-					offset = Integer.MAX_VALUE;
+					result = text.substring(offset);
-					return result;
+					if (!ignoreEmpty || !result.isEmpty()) {
+						// 返回非空串
+						offset = Integer.MAX_VALUE;
+						return result;
+					}
 				}
+				return null;
 			}
-			return null;
-		}
 
-		// 找到新的分隔符位置
+			// 找到新的分隔符位置
-		final String result = text.substring(offset, start);
+			result = text.substring(offset, start);
-		offset = finder.end(start);
+			offset = finder.end(start);
-
+		} while (ignoreEmpty && result.isEmpty()); // 空串则继续循环
-		if (ignoreEmpty && result.isEmpty()) {
-			// 发现空串且需要忽略时，跳过之
-			return computeNext();
-		}
 
 		count++;
 		return result;

hutool-core/src/main/java/cn/hutool/core/util/HexUtil.java

@@ -379,15 +379,24 @@ public class HexUtil {
 	 * @return 格式化后的字符串
 	 */
 	public static String format(final String hexStr, String prefix) {
+		if (StrUtil.isEmpty(hexStr)) {
+			return StrUtil.EMPTY;
+		}
 		if (null == prefix) {
 			prefix = StrUtil.EMPTY;
 		}
 
 		final int length = hexStr.length();
 		final StringBuilder builder = StrUtil.builder(length + length / 2 + (length / 2 * prefix.length()));
-		builder.append(prefix).append(hexStr.charAt(0)).append(hexStr.charAt(1));
+
-		for (int i = 2; i < length - 1; i += 2) {
+		for (int i = 0; i < length; i++) {
-			builder.append(CharUtil.SPACE).append(prefix).append(hexStr.charAt(i)).append(hexStr.charAt(i + 1));
+			if (i % 2 == 0) {
+				if (i != 0) {
+					builder.append(CharUtil.SPACE);
+				}
+				builder.append(prefix);
+			}
+			builder.append(hexStr.charAt(i));
 		}
 		return builder.toString();
 	}

hutool-core/src/test/java/cn/hutool/core/text/split/SplitIterTest.java

@@ -6,6 +6,8 @@ import cn.hutool.core.text.finder.PatternFinder;
 import cn.hutool.core.text.finder.StrFinder;
 import org.junit.jupiter.api.Test;
 
+import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.regex.Pattern;
 
@@ -153,4 +155,18 @@ public class SplitIterTest {
 			assertEquals(1, strings.size());
 		});
 	}
+
+	@Test
+	public void issue4169Test() {
+		StringBuilder sb = new StringBuilder();
+		for (int i = 0; i < 20000; i++) { // 1万次连续分隔符，模拟递归深度风险场景
+			sb.append(",");
+		}
+		sb.append("test");
+
+		SplitIter iter = new SplitIter(sb.toString(), new StrFinder(",",false), 0, true);
+		List<String> result = iter.toList(false);
+
+		assertEquals(Collections.singletonList("test"), result);
+	}
 }

hutool-core/src/test/java/cn/hutool/core/util/HexUtilTest.java

@@ -116,4 +116,35 @@ public class HexUtilTest {
 		final String hex3 = "#FF";
 		assertEquals(new BigInteger("FF", 16), HexUtil.toBigInteger(hex3));
 	}
+
+	@Test
+	public void testFormatEmpty() {
+		String result = HexUtil.format("");
+		assertEquals("", result);
+	}
+
+	@Test
+	public void testFormatSingleChar() {
+		String result = HexUtil.format("1");
+		assertEquals("1", result);
+	}
+
+	@Test
+	public void testFormatOddLength() {
+		String result = HexUtil.format("123");
+		assertEquals("12 3", result);
+	}
+
+	@Test
+	public void testFormatWithPrefixSingleChar() {
+		String result = HexUtil.format("1", "0x");
+		assertEquals("0x1", result);
+	}
+
+	@Test
+	public void testFormatWithPrefixOddLength() {
+		String result = HexUtil.format("123", "0x");
+		assertEquals("0x12 0x3", result);
+	}
+
 }

hutool-poi/src/test/java/cn/hutool/poi/excel/Issue4146Test.java

@@ -0,0 +1,66 @@
+package cn.hutool.poi.excel;
+
+import cn.hutool.poi.excel.style.StyleUtil;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import org.apache.poi.ss.usermodel.BorderStyle;
+import org.apache.poi.ss.usermodel.CellStyle;
+import org.apache.poi.ss.usermodel.FillPatternType;
+import org.apache.poi.ss.usermodel.IndexedColors;
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class Issue4146Test {
+	@Test
+	@Disabled
+	public void writeSheetWithStyleTest() {
+		ExcelWriter writer = ExcelUtil.getWriter("d:\\test\\issue4146.xlsx", "表格1");
+
+		List<TestUser> list = new ArrayList<>();
+		TestUser test = new TestUser("张三", 18, 90.0, 0.9878);
+		list.add(test);
+		test = new TestUser("李四", 18, 79.5, 0.8311);
+		list.add(test);
+		test = new TestUser("王五", 18, 89.9, 0.6932);
+		list.add(test);
+		test = new TestUser("赵六", 18, 69.9, 0.7912);
+		list.add(test);
+		test = new TestUser("孙七", 18, 79.9, 0.6432);
+		list.add(test);
+
+		writer.addHeaderAlias("name", "姓名");
+		writer.addHeaderAlias("age", "年龄");
+		writer.addHeaderAlias("score", "分数");
+		writer.addHeaderAlias("zb", "占比");
+
+		writer.setOnlyAlias(true);
+		writer.write(list, true);
+
+		// 百分比的单元格样式必须单独创建，使用StyleSet中的样式修改则会修改全局样式
+		CellStyle percentCellStyle = writer.createCellStyle();
+		percentCellStyle.setDataFormat(writer.getWorkbook().createDataFormat().getFormat("0.00%"));
+		// 填充背景颜色，必须指定FillPatternType才有效
+		StyleUtil.setColor(percentCellStyle, IndexedColors.YELLOW, FillPatternType.SOLID_FOREGROUND);
+		// 设置边框颜色和粗细
+		StyleUtil.setBorder(percentCellStyle, BorderStyle.THIN, IndexedColors.BLACK);
+		final int rowCount = writer.getRowCount();
+		// 设置列样式无效，除非将默认样式清除，因此必须在写出数据后为单元格指定自定义的样式
+		for (int i = 1; i < rowCount; i++) {
+			writer.setStyle(percentCellStyle, 3, i);
+		}
+
+		writer.close();
+	}
+
+	@Data
+	@AllArgsConstructor
+	static class TestUser {
+		private String name;
+		private Integer age;
+		private Double score;
+		private Double zb;
+	}
+}