package com.alibaba.nacos.client;

import com.alibaba.nacos.client.utils.StringUtils;
import org.junit.Test;

import java.util.ArrayList;
import java.util.Collection;

import static org.junit.Assert.*;
import static com.alibaba.nacos.client.utils.StringUtils.*;

public class StringUtilsTest {

    @Test
    public void testisNotBlank() {
        assertTrue(isNotBlank("foo"));

        assertFalse(isNotBlank(" "));
        assertFalse(isNotBlank(null));
    }

    @Test
    public void testIsNotEmpty() {
        assertFalse(isNotEmpty(""));

        assertTrue(isNotEmpty("foo"));
    }

    @Test
    public void testDefaultIfEmpty() {
        assertEquals("foo", defaultIfEmpty("", "foo"));
        assertEquals("bar", defaultIfEmpty("bar", "foo"));
    }

    @Test
    public void testEquals() {
        assertTrue(StringUtils.equals("foo", "foo"));

        assertFalse(StringUtils.equals("bar", "foo"));
        assertFalse(StringUtils.equals(" ", "foo"));
        assertFalse(StringUtils.equals("foo", null));
    }

    @Test
    public void testSubstringBetween() {
        assertNull(substringBetween(null, null, null));
        assertNull(substringBetween("", "foo", ""));
        assertNull(substringBetween("foo", "bar", "baz"));

        assertEquals("", substringBetween("foo", "foo", ""));
    }

    @Test
    public void testJoin() {
        assertNull(join(null, ""));

        Collection collection = new ArrayList();
        collection.add("foo");
        collection.add("bar");
        assertEquals("foo,bar", join(collection, ","));
    }
}

Add unit tests for com.alibaba.nacos.client.utils.StringUtils
Add unit tests for com.alibaba.nacos.client.utils.StringUtils

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