diff --git a/pom.xml b/pom.xml
index 90bae53..3d7f397 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <artifactId>GpxAndroidSdk</artifactId>
     <groupId>me.bvn13.sdk.android.gpx</groupId>
-    <version>1.1</version>
+    <version>1.2</version>
 
     <packaging>jar</packaging>
 
@@ -82,15 +82,9 @@
             <version>${kotlin-junit.version}</version>
         </dependency>
         <dependency>
-            <groupId>io.kotest</groupId>
-            <artifactId>kotest-runner-junit5-jvm</artifactId>
-            <version>${kotest.version}</version>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>io.kotest</groupId>
-            <artifactId>kotest-assertions-core-jvm</artifactId>
-            <version>${kotest.version}</version>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <version>${jupiter.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/src/main/kotlin/me/bvn13/sdk/android/gpx/GpxWriter.kt b/src/main/kotlin/me/bvn13/sdk/android/gpx/GpxWriter.kt
index 6a651ed..67cc664 100644
--- a/src/main/kotlin/me/bvn13/sdk/android/gpx/GpxWriter.kt
+++ b/src/main/kotlin/me/bvn13/sdk/android/gpx/GpxWriter.kt
@@ -99,11 +99,11 @@ fun GpxType.toXmlString(clock: Clock?): String = """
     xsi:schemaLocation="$SCHEMA_LOCATION">
     <time>${now(clock)}</time>
     ${this.metadata.toXmlString()}
-    ${this.wpt?.toXmlString()}
-    ${this.rte?.toXmlString()}
-    ${this.trk?.toXmlString()}
+    ${this.wpt?.toXmlString() ?: ""}
+    ${this.rte?.toXmlString() ?: ""}
+    ${this.trk?.toXmlString() ?: ""}
     </gpx>
-""".trim()
+""".trim().removeEmptyStrings()
 
 fun MetadataType.toXmlString(): String = """
       <metadata>
@@ -113,16 +113,13 @@ fun MetadataType.toXmlString(): String = """
       <name>${this.authorName}</name>
       </author>
       </metadata>
-""".trim()
+""".trim().removeEmptyStrings()
 
-private fun now(clock: Clock?) = OffsetDateTime.now(clock ?: Clock.systemDefaultZone()).format(DTF)
-
-fun WptType.toXmlString(nodeName: String? = null) =
-    if (nodeName != null) {
-        this.toXmlString(nodeName)
-    } else {
-        this.toXmlString("wpt")
-    }
+fun WptType.toXmlString(nodeName: String? = null) = if (nodeName != null) {
+    this.toXmlString(nodeName)
+} else {
+    this.toXmlString("wpt")
+}
 
 @JvmName("toXmlStringNamed")
 fun WptType.toXmlString(nodeName: String) = """
@@ -135,19 +132,19 @@ fun WptType.toXmlString(nodeName: String) = """
     ${toXmlString(cmt, "cmt")}
     ${toXmlString(desc, "desc")}
     ${toXmlString(src, "src")}
-    ${link?.toXmlString()}
+    ${link?.toXmlString() ?: ""}
     ${toXmlString(sym, "sym")}
     ${toXmlString(type, "type")}
-    ${fix?.toXmlString()}
+    ${fix?.toXmlString() ?: ""}
     ${toXmlString(sat, "sat")}
     ${toXmlString(hdop, "hdop")}
     ${toXmlString(vdop, "vdop")}
     ${toXmlString(pdop, "pdop")}
     ${toXmlString(ageofgpsdata, "ageofgpsdata")}
     ${toXmlString(dgpsid, "dgpsid")}
-    ${extensions?.toXmlString()}
+    ${extensions?.toXmlString() ?: ""}
     </${nodeName}>
-""".trim()
+""".trim().removeEmptyStrings()
 
 fun RteType.toXmlString() = """
     <rte>
@@ -155,13 +152,13 @@ fun RteType.toXmlString() = """
     ${toXmlString(this.cmt, "cmt")}
     ${toXmlString(this.desc, "desc")}
     ${toXmlString(this.src, "src")}
-    ${this.link?.toXmlString()}
+    ${this.link?.toXmlString() ?: ""}
     ${toXmlString(this.number, "number")}
     ${toXmlString(this.type, "type")}
-    ${this.extensions?.toXmlString()}
-    ${this.rtept?.toXmlString()}
+    ${this.extensions?.toXmlString() ?: ""}
+    ${this.rtept?.toXmlString() ?: ""}
     </rte>
-""".trim()
+""".trim().removeEmptyStrings()
 
 fun TrkType.toXmlString() = """
     <trk>
@@ -169,24 +166,47 @@ fun TrkType.toXmlString() = """
     ${toXmlString(this.cmt, "cmt")}
     ${toXmlString(this.desc, "desc")}
     ${toXmlString(this.src, "src")}
-    ${this.link?.toXmlString()}
+    ${this.link?.toXmlString() ?: ""}
     ${toXmlString(this.number, "number")}
     ${toXmlString(this.type, "type")}
-    ${this.extensions?.toXmlString()}
-    ${this.trkseg?.toXmlString()}
+    ${this.extensions?.toXmlString() ?: ""}
+    ${this.trkseg?.toXmlString() ?: ""}
     </trk>
-""".trim()
+""".trim().removeEmptyStrings()
 
-fun List<WptType>.toXmlString(nodeName: String?) =
-    this.joinToString(prefix = "", postfix = "", separator = "") {
-        it.toXmlString(nodeName)
-    }
+fun LinkType.toXmlString() = """
+    <link href="${this.href}">
+    <text>${this.text}</text>
+    <type>${this.type}</type>
+    </link>
+""".trim().removeEmptyStrings()
+
+fun FixType.toXmlString() = """
+    <fix>${this.value}</fix>
+""".trim().removeEmptyStrings()
+
+fun ExtensionType.toXmlString() = """
+        <${this.nodeName}${toXmlString(this.parameters)}>${this.value ?: ""}</${this.nodeName}>
+    """.trim().removeEmptyStrings()
+
+fun TrksegType.toXmlString() = """
+    <trkseg>
+    ${this.trkpt?.toXmlString("trkpt") ?: ""}
+    </trkseg>
+""".trim().removeEmptyStrings()
+
+fun List<WptType>.toXmlString(nodeName: String?) = this.joinToString(prefix = "\n", postfix = "", separator = "") {
+    it.toXmlString(nodeName)
+}
+
+fun List<ExtensionType>.toXmlString() = this.joinToString(
+    prefix = "<extensions>\n", postfix = "\n</extensions>", separator = "\n", transform = ExtensionType::toXmlString
+)
 
 @JvmName("toXmlStringWptType")
-fun List<WptType>.toXmlString() =
-    this.joinToString(prefix = "", postfix = "", separator = "") {
-        it.toXmlString()
-    }
+fun List<WptType>.toXmlString() = this.joinToString(prefix = "", postfix = "", separator = "") {
+    it.toXmlString()
+}
 
 @JvmName("toXmlStringLinkType")
 fun List<LinkType>.toXmlString() =
@@ -204,75 +224,41 @@ fun List<TrkType>.toXmlString() =
 fun List<TrksegType>.toXmlString() =
     this.joinToString(prefix = "", postfix = "", separator = "", transform = TrksegType::toXmlString)
 
-fun List<ExtensionType>.toXmlString() =
-    this.joinToString(
-        prefix = "<extensions>\n",
-        postfix = "\n</extensions>",
-        separator = "\n",
-        transform = ExtensionType::toXmlString
-    )
+fun toXmlString(value: String?, nodeName: String) = if (value != null) {
+    "<${nodeName}>${value}</${nodeName}>"
+} else {
+    ""
+}
 
-fun LinkType.toXmlString() = """
-    <link href="${this.href}">
-    <text>${this.text}</text>
-    <type>${this.type}</type>
-    </link>
-""".trim()
+fun toXmlString(value: Int?, nodeName: String) = if (value != null) {
+    "<${nodeName}>${value}</${nodeName}>"
+} else {
+    ""
+}
 
-fun FixType.toXmlString() = """
-    <fix>${this.value}</fix>
-""".trim()
+fun toXmlString(value: Double?, nodeName: String) = if (value != null) {
+    "<${nodeName}>${value}</${nodeName}>"
+} else {
+    ""
+}
 
-fun ExtensionType.toXmlString() = """
-        <${this.nodeName}${toXmlString(this.parameters)}>${this.value ?: ""}</${this.nodeName}>
-    """.trim()
+fun toXmlString(value: OffsetDateTime?, nodeName: String) = if (value != null) {
+    "<${nodeName}>${value.format(DTF)}</${nodeName}>"
+} else {
+    ""
+}
 
-fun TrksegType.toXmlString() = """
-    <trkseg>
-    ${this.trkpt?.toXmlString("trkpt")}
-    </trkseg>
-""".trim()
+fun toXmlString(value: Map<String, String>?) = value?.entries?.joinToString(separator = "") {
+    " ${it.key}=\"${it.value}\""
+} ?: ""
 
-fun toXmlString(value: String?, nodeName: String) =
-    if (value != null) {
-        """
-            <${nodeName}>${value}</${nodeName}>
-        """.trim()
-    } else {
-        ""
-    }
+private fun now(clock: Clock?) = OffsetDateTime.now(clock ?: Clock.systemDefaultZone()).format(DTF)
 
-fun toXmlString(value: Int?, nodeName: String) =
-    if (value != null) {
-        """
-            <${nodeName}>${value}</${nodeName}>
-        """.trim()
-    } else {
-        ""
-    }
-
-fun toXmlString(value: Double?, nodeName: String) =
-    if (value != null) {
-        """
-            <${nodeName}>${value}</${nodeName}>
-        """.trim()
-    } else {
-        ""
-    }
-
-fun toXmlString(value: OffsetDateTime?, nodeName: String) =
-    if (value != null) {
-        """
-            <${nodeName}>${value.format(DTF)}</${nodeName}>
-        """.trim()
-    } else {
-        ""
-    }
-
-fun toXmlString(value: Map<String, String>?) =
-    value?.entries?.joinToString(separator = "") {
-        " ${it.key}=\"${it.value}\""
-    } ?: ""
+private fun String.removeEmptyStrings() = this.lineSequence().map {
+    it.trim()
+}.filter {
+    it != ""
+}.joinToString("\n")
 
 class GpxWriter {
     companion object {
@@ -281,9 +267,9 @@ class GpxWriter {
         const val XMLNS_XSI = "http://www.w3.org/2001/XMLSchema-instance"
         const val SCHEMA_LOCATION = "http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd"
 
-        internal val DTF = DateTimeFormatterBuilder()
-            .append(ISO_LOCAL_DATE_TIME) // use the existing formatter for date time
-            .appendOffset("+HH:MM", "+00:00") // set 'noOffsetText' to desired '+00:00'
-            .toFormatter()
+        internal val DTF =
+            DateTimeFormatterBuilder().append(ISO_LOCAL_DATE_TIME) // use the existing formatter for date time
+                .appendOffset("+HH:MM", "+00:00") // set 'noOffsetText' to desired '+00:00'
+                .toFormatter()
     }
 }
diff --git a/src/test/kotlin/me/bvn13/sdk/android/gpx/GpxWriterTest.kt b/src/test/kotlin/me/bvn13/sdk/android/gpx/GpxWriterTest.kt
index 6bd5caa..ce1807e 100644
--- a/src/test/kotlin/me/bvn13/sdk/android/gpx/GpxWriterTest.kt
+++ b/src/test/kotlin/me/bvn13/sdk/android/gpx/GpxWriterTest.kt
@@ -59,7 +59,7 @@ APPENDIX: How to apply the Apache License to your work.
 
 To apply the Apache License to your work, attach the following boilerplate notice, with the fields enclosed by brackets "[]" replaced with your own identifying information. (Don't include the brackets!)  The text should be enclosed in the appropriate comment syntax for the file format. We also recommend that a file or class name and description of purpose be included on the same "printed page" as the copyright notice for easier identification within third-party archives.
 
-Copyright [yyyy] [name of copyright owner]
+Copyright bvn13, 2022
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -77,184 +77,246 @@ limitations under the License.
 
 package me.bvn13.sdk.android.gpx
 
-import io.kotest.core.spec.style.FunSpec
+import org.junit.jupiter.api.DisplayName
+import org.junit.jupiter.api.Test
 import java.time.*
 import kotlin.test.assertEquals
 
-class GpxWriterTest : FunSpec() {
-    init {
-        test("first test") {
-            val clock = Clock.fixed(
-                LocalDateTime.of(2022, 9, 24, 15, 4, 0, 0).toInstant(ZoneOffset.ofHours(3)), ZoneId.of("Europe/Moscow")
-            )
+class GpxWriterTest {
+    @DisplayName("test minimum")
+    @Test
+    fun testMinimum() {
+        val clock = Clock.fixed(
+            LocalDateTime.of(2022, 9, 24, 15, 4, 0, 0).toInstant(ZoneOffset.ofHours(3)), ZoneId.of("Europe/Moscow")
+        )
 
-            val gpxType = GpxType(
-                MetadataType("test name", description = "test description", authorName = "bvn13"),
-                wpt = listOf(
-                    WptType(
-                        lat = 14.64736838389662,
-                        lon = 7.93212890625,
-                        ele = 10.toDouble(),
-                        time = OffsetDateTime.now(clock),
-                        magvar = 3.toDouble(),
-                        geoidheight = 45.toDouble(),
-                        name = "test point 1",
-                        cmt = "comment 1",
-                        desc = "description of point 1",
-                        link = listOf(
-                            LinkType(
-                                href = "http://link-to.site.href",
-                                text = "text",
-                                type = "hyperlink"
-                            ),
-                            LinkType(
-                                href = "http://link2-to.site.href",
-                                text = "text2",
-                                type = "hyperlink2"
-                            )
-                        ),
-                        src = "source 1",
-                        sym = "sym 1",
-                        type = "type 1",
-                        fix = FixType.DGPS,
-                        sat = 1,
-                        hdop = 55.toDouble(),
-                        vdop = 66.toDouble(),
-                        pdop = 77.toDouble(),
-                        ageofgpsdata = 44,
-                        dgpsid = 88,
-                        extensions = listOf(
-                            ExtensionType(
-                                "extension1",
-                                parameters = mapOf(Pair("first", "second"), Pair("third", "fours"))
-                            ),
-                            ExtensionType(
-                                "extension2",
-                                parameters = mapOf(Pair("aa", "bb"), Pair("cc", "dd"))
-                            )
-                        )
-                    )
-                ),
-                rte = listOf(
-                    RteType(
-                        name = "rte name",
-                        cmt = "cmt",
-                        desc = "desc",
-                        src = "src",
-                        link = listOf(
-                            LinkType(
-                                href = "https://new.link.rte",
-                                text = "new text rte",
-                                type = "hyperlink"
-                            )
-                        ),
-                        number = 1234,
-                        type = "route",
-                        extensions = listOf(
-                            ExtensionType(
-                                "ext-1",
-                                value = "value1"
-                            )
-                        ),
-                        rtept = listOf(
-                            WptType(
-                                lat = 14.64736838389662,
-                                lon = 7.93212890625,
-                                ele = 10.toDouble(),
-                                time = OffsetDateTime.now(clock),
-                                magvar = 3.toDouble(),
-                                geoidheight = 45.toDouble(),
-                                name = "test point 1",
-                                cmt = "comment 1",
-                                desc = "description of point 1",
-                                link = listOf(
-                                    LinkType(
-                                        href = "http://link-to.site.href",
-                                        text = "text",
-                                        type = "hyperlink"
-                                    ),
-                                    LinkType(
-                                        href = "http://link2-to.site.href",
-                                        text = "text2",
-                                        type = "hyperlink2"
-                                    )
-                                ),
-                                src = "source 1",
-                                sym = "sym 1",
-                                type = "type 1",
-                                fix = FixType.DGPS,
-                                sat = 1,
-                                hdop = 55.toDouble(),
-                                vdop = 66.toDouble(),
-                                pdop = 77.toDouble(),
-                                ageofgpsdata = 44,
-                                dgpsid = 88,
-                                extensions = listOf(
-                                    ExtensionType(
-                                        "extension1",
-                                        parameters = mapOf(Pair("first", "second"), Pair("third", "fours"))
-                                    ),
-                                    ExtensionType(
-                                        "extension2",
-                                        parameters = mapOf(Pair("aa", "bb"), Pair("cc", "dd"))
-                                    )
+        val gpxType = GpxType(
+            MetadataType("test name"),
+            trk = listOf(
+                TrkType(
+                    name = "track1",
+                    trkseg = listOf(
+                        TrksegType(
+                            listOf(
+                                WptType(
+                                    lat = 123.toDouble(),
+                                    lon = 321.toDouble()
                                 )
                             )
                         )
                     )
-                ),
-                trk = listOf(
-                    TrkType(
-                        name = "track 1",
-                        cmt = "comment track 1",
-                        desc = "desc track 1",
-                        src = "src track 1",
-                        number = 1234,
-                        type = "type 1",
-                        trkseg = listOf(
-                            TrksegType(
-                                listOf(
-                                    WptType(
-                                        lat = 14.64736838389662,
-                                        lon = 7.93212890625,
-                                        ele = 10.toDouble(),
-                                        time = OffsetDateTime.now(clock),
-                                        magvar = 3.toDouble(),
-                                        geoidheight = 45.toDouble(),
-                                        name = "test point 1",
-                                        cmt = "comment 1",
-                                        desc = "description of point 1",
-                                        link = listOf(
-                                            LinkType(
-                                                href = "http://link-to.site.href",
-                                                text = "text",
-                                                type = "hyperlink"
-                                            ),
-                                            LinkType(
-                                                href = "http://link2-to.site.href",
-                                                text = "text2",
-                                                type = "hyperlink2"
-                                            )
+                )
+            )
+        )
+
+        assertEquals(
+            """
+            <?xml version="1.0" encoding="UTF-8"?>
+            <gpx
+            xmlns="http://www.topografix.com/GPX/1/1"
+            version="1.1"
+            creator="me.bvn13.sdk.android.gpx"
+            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+            xsi:schemaLocation="http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd">
+            <time>2022-09-24T15:04:00+03:00</time>
+            <metadata>
+            <name>test name</name>
+            <desc></desc>
+            <author>
+            <name></name>
+            </author>
+            </metadata>
+            <trk>
+            <name>track1</name>
+            <trkseg>
+            <trkpt lat="123.0" lon="321.0">
+            </trkpt>
+            </trkseg>
+            </trk>
+            </gpx>
+            """.trim()
+            .lineSequence()
+            .map {
+                it.trim()
+            }
+            .joinToString("\n"),
+            gpxType.toXmlString(clock)
+        )
+    }
+
+    @DisplayName("test maximum")
+    @Test
+    fun maximumTest() {
+        val clock = Clock.fixed(
+            LocalDateTime.of(2022, 9, 24, 15, 4, 0, 0).toInstant(ZoneOffset.ofHours(3)), ZoneId.of("Europe/Moscow")
+        )
+
+        val gpxType = GpxType(
+            MetadataType("test name", description = "test description", authorName = "bvn13"),
+            wpt = listOf(
+                WptType(
+                    lat = 14.64736838389662,
+                    lon = 7.93212890625,
+                    ele = 10.toDouble(),
+                    time = OffsetDateTime.now(clock),
+                    magvar = 3.toDouble(),
+                    geoidheight = 45.toDouble(),
+                    name = "test point 1",
+                    cmt = "comment 1",
+                    desc = "description of point 1",
+                    link = listOf(
+                        LinkType(
+                            href = "http://link-to.site.href",
+                            text = "text",
+                            type = "hyperlink"
+                        ),
+                        LinkType(
+                            href = "http://link2-to.site.href",
+                            text = "text2",
+                            type = "hyperlink2"
+                        )
+                    ),
+                    src = "source 1",
+                    sym = "sym 1",
+                    type = "type 1",
+                    fix = FixType.DGPS,
+                    sat = 1,
+                    hdop = 55.toDouble(),
+                    vdop = 66.toDouble(),
+                    pdop = 77.toDouble(),
+                    ageofgpsdata = 44,
+                    dgpsid = 88,
+                    extensions = listOf(
+                        ExtensionType(
+                            "extension1",
+                            parameters = mapOf(Pair("first", "second"), Pair("third", "fours"))
+                        ),
+                        ExtensionType(
+                            "extension2",
+                            parameters = mapOf(Pair("aa", "bb"), Pair("cc", "dd"))
+                        )
+                    )
+                )
+            ),
+            rte = listOf(
+                RteType(
+                    name = "rte name",
+                    cmt = "cmt",
+                    desc = "desc",
+                    src = "src",
+                    link = listOf(
+                        LinkType(
+                            href = "https://new.link.rte",
+                            text = "new text rte",
+                            type = "hyperlink"
+                        )
+                    ),
+                    number = 1234,
+                    type = "route",
+                    extensions = listOf(
+                        ExtensionType(
+                            "ext-1",
+                            value = "value1"
+                        )
+                    ),
+                    rtept = listOf(
+                        WptType(
+                            lat = 14.64736838389662,
+                            lon = 7.93212890625,
+                            ele = 10.toDouble(),
+                            time = OffsetDateTime.now(clock),
+                            magvar = 3.toDouble(),
+                            geoidheight = 45.toDouble(),
+                            name = "test point 1",
+                            cmt = "comment 1",
+                            desc = "description of point 1",
+                            link = listOf(
+                                LinkType(
+                                    href = "http://link-to.site.href",
+                                    text = "text",
+                                    type = "hyperlink"
+                                ),
+                                LinkType(
+                                    href = "http://link2-to.site.href",
+                                    text = "text2",
+                                    type = "hyperlink2"
+                                )
+                            ),
+                            src = "source 1",
+                            sym = "sym 1",
+                            type = "type 1",
+                            fix = FixType.DGPS,
+                            sat = 1,
+                            hdop = 55.toDouble(),
+                            vdop = 66.toDouble(),
+                            pdop = 77.toDouble(),
+                            ageofgpsdata = 44,
+                            dgpsid = 88,
+                            extensions = listOf(
+                                ExtensionType(
+                                    "extension1",
+                                    parameters = mapOf(Pair("first", "second"), Pair("third", "fours"))
+                                ),
+                                ExtensionType(
+                                    "extension2",
+                                    parameters = mapOf(Pair("aa", "bb"), Pair("cc", "dd"))
+                                )
+                            )
+                        )
+                    )
+                )
+            ),
+            trk = listOf(
+                TrkType(
+                    name = "track 1",
+                    cmt = "comment track 1",
+                    desc = "desc track 1",
+                    src = "src track 1",
+                    number = 1234,
+                    type = "type 1",
+                    trkseg = listOf(
+                        TrksegType(
+                            listOf(
+                                WptType(
+                                    lat = 14.64736838389662,
+                                    lon = 7.93212890625,
+                                    ele = 10.toDouble(),
+                                    time = OffsetDateTime.now(clock),
+                                    magvar = 3.toDouble(),
+                                    geoidheight = 45.toDouble(),
+                                    name = "test point 1",
+                                    cmt = "comment 1",
+                                    desc = "description of point 1",
+                                    link = listOf(
+                                        LinkType(
+                                            href = "http://link-to.site.href",
+                                            text = "text",
+                                            type = "hyperlink"
                                         ),
-                                        src = "source 1",
-                                        sym = "sym 1",
-                                        type = "type 1",
-                                        fix = FixType.DGPS,
-                                        sat = 1,
-                                        hdop = 55.toDouble(),
-                                        vdop = 66.toDouble(),
-                                        pdop = 77.toDouble(),
-                                        ageofgpsdata = 44,
-                                        dgpsid = 88,
-                                        extensions = listOf(
-                                            ExtensionType(
-                                                "extension1",
-                                                parameters = mapOf(Pair("first", "second"), Pair("third", "fours"))
-                                            ),
-                                            ExtensionType(
-                                                "extension2",
-                                                parameters = mapOf(Pair("aa", "bb"), Pair("cc", "dd"))
-                                            )
+                                        LinkType(
+                                            href = "http://link2-to.site.href",
+                                            text = "text2",
+                                            type = "hyperlink2"
+                                        )
+                                    ),
+                                    src = "source 1",
+                                    sym = "sym 1",
+                                    type = "type 1",
+                                    fix = FixType.DGPS,
+                                    sat = 1,
+                                    hdop = 55.toDouble(),
+                                    vdop = 66.toDouble(),
+                                    pdop = 77.toDouble(),
+                                    ageofgpsdata = 44,
+                                    dgpsid = 88,
+                                    extensions = listOf(
+                                        ExtensionType(
+                                            "extension1",
+                                            parameters = mapOf(Pair("first", "second"), Pair("third", "fours"))
+                                        ),
+                                        ExtensionType(
+                                            "extension2",
+                                            parameters = mapOf(Pair("aa", "bb"), Pair("cc", "dd"))
                                         )
                                     )
                                 )
@@ -263,148 +325,151 @@ class GpxWriterTest : FunSpec() {
                     )
                 )
             )
+        )
 
-            assertEquals(
-                """
-                    <?xml version="1.0" encoding="UTF-8"?>
-    <gpx
-    xmlns="http://www.topografix.com/GPX/1/1"
-    version="1.1"
-    creator="me.bvn13.sdk.android.gpx"
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd">
-    <time>2022-09-24T15:04:00+03:00</time>
-    <metadata>
-      <name>test name</name>
-      <desc>test description</desc>
-      <author>
-      <name>bvn13</name>
-      </author>
-      </metadata>
-    <wpt lat="14.64736838389662" lon="7.93212890625">
-    <ele>10.0</ele>
-    <time>2022-09-24T15:04:00+03:00</time>
-    <magvar>3.0</magvar>
-    <geoidheight>45.0</geoidheight>
-    <name>test point 1</name>
-    <cmt>comment 1</cmt>
-    <desc>description of point 1</desc>
-    <src>source 1</src>
-    <link href="http://link-to.site.href">
-    <text>text</text>
-    <type>hyperlink</type>
-    </link>
-<link href="http://link2-to.site.href">
-    <text>text2</text>
-    <type>hyperlink2</type>
-    </link>
-    <sym>sym 1</sym>
-    <type>type 1</type>
-    <fix>dgps</fix>
-    <sat>1</sat>
-    <hdop>55.0</hdop>
-    <vdop>66.0</vdop>
-    <pdop>77.0</pdop>
-    <ageofgpsdata>44</ageofgpsdata>
-    <dgpsid>88</dgpsid>
-    <extensions>
-<extension1 first="second" third="fours"></extension1>
-<extension2 aa="bb" cc="dd"></extension2>
-</extensions>
-    </wpt>
-    <rte>
-    <name>rte name</name>
-    <cmt>cmt</cmt>
-    <desc>desc</desc>
-    <src>src</src>
-    <link href="https://new.link.rte">
-    <text>new text rte</text>
-    <type>hyperlink</type>
-    </link>
-    <number>1234</number>
-    <type>route</type>
-    <extensions>
-<ext-1>value1</ext-1>
-</extensions>
-    <wpt lat="14.64736838389662" lon="7.93212890625">
-    <ele>10.0</ele>
-    <time>2022-09-24T15:04:00+03:00</time>
-    <magvar>3.0</magvar>
-    <geoidheight>45.0</geoidheight>
-    <name>test point 1</name>
-    <cmt>comment 1</cmt>
-    <desc>description of point 1</desc>
-    <src>source 1</src>
-    <link href="http://link-to.site.href">
-    <text>text</text>
-    <type>hyperlink</type>
-    </link>
-<link href="http://link2-to.site.href">
-    <text>text2</text>
-    <type>hyperlink2</type>
-    </link>
-    <sym>sym 1</sym>
-    <type>type 1</type>
-    <fix>dgps</fix>
-    <sat>1</sat>
-    <hdop>55.0</hdop>
-    <vdop>66.0</vdop>
-    <pdop>77.0</pdop>
-    <ageofgpsdata>44</ageofgpsdata>
-    <dgpsid>88</dgpsid>
-    <extensions>
-<extension1 first="second" third="fours"></extension1>
-<extension2 aa="bb" cc="dd"></extension2>
-</extensions>
-    </wpt>
-    </rte>
-    <trk>
-    <name>track 1</name>
-    <cmt>comment track 1</cmt>
-    <desc>desc track 1</desc>
-    <src>src track 1</src>
-    null
-    <number>1234</number>
-    <type>type 1</type>
-    null
-    <trkseg>
-    <trkpt lat="14.64736838389662" lon="7.93212890625">
-    <ele>10.0</ele>
-    <time>2022-09-24T15:04:00+03:00</time>
-    <magvar>3.0</magvar>
-    <geoidheight>45.0</geoidheight>
-    <name>test point 1</name>
-    <cmt>comment 1</cmt>
-    <desc>description of point 1</desc>
-    <src>source 1</src>
-    <link href="http://link-to.site.href">
-    <text>text</text>
-    <type>hyperlink</type>
-    </link>
-<link href="http://link2-to.site.href">
-    <text>text2</text>
-    <type>hyperlink2</type>
-    </link>
-    <sym>sym 1</sym>
-    <type>type 1</type>
-    <fix>dgps</fix>
-    <sat>1</sat>
-    <hdop>55.0</hdop>
-    <vdop>66.0</vdop>
-    <pdop>77.0</pdop>
-    <ageofgpsdata>44</ageofgpsdata>
-    <dgpsid>88</dgpsid>
-    <extensions>
-<extension1 first="second" third="fours"></extension1>
-<extension2 aa="bb" cc="dd"></extension2>
-</extensions>
-    </trkpt>
-    </trkseg>
-    </trk>
-    </gpx>
-        """.trim(),
-                gpxType.toXmlString(clock)
-            )
-        }
+        assertEquals(
+            """
+            <?xml version="1.0" encoding="UTF-8"?>
+            <gpx
+            xmlns="http://www.topografix.com/GPX/1/1"
+            version="1.1"
+            creator="me.bvn13.sdk.android.gpx"
+            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+            xsi:schemaLocation="http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd">
+            <time>2022-09-24T15:04:00+03:00</time>
+            <metadata>
+            <name>test name</name>
+            <desc>test description</desc>
+            <author>
+            <name>bvn13</name>
+            </author>
+            </metadata>
+            <wpt lat="14.64736838389662" lon="7.93212890625">
+            <ele>10.0</ele>
+            <time>2022-09-24T15:04:00+03:00</time>
+            <magvar>3.0</magvar>
+            <geoidheight>45.0</geoidheight>
+            <name>test point 1</name>
+            <cmt>comment 1</cmt>
+            <desc>description of point 1</desc>
+            <src>source 1</src>
+            <link href="http://link-to.site.href">
+            <text>text</text>
+            <type>hyperlink</type>
+            </link>
+            <link href="http://link2-to.site.href">
+            <text>text2</text>
+            <type>hyperlink2</type>
+            </link>
+            <sym>sym 1</sym>
+            <type>type 1</type>
+            <fix>dgps</fix>
+            <sat>1</sat>
+            <hdop>55.0</hdop>
+            <vdop>66.0</vdop>
+            <pdop>77.0</pdop>
+            <ageofgpsdata>44</ageofgpsdata>
+            <dgpsid>88</dgpsid>
+            <extensions>
+            <extension1 first="second" third="fours"></extension1>
+            <extension2 aa="bb" cc="dd"></extension2>
+            </extensions>
+            </wpt>
+            <rte>
+            <name>rte name</name>
+            <cmt>cmt</cmt>
+            <desc>desc</desc>
+            <src>src</src>
+            <link href="https://new.link.rte">
+            <text>new text rte</text>
+            <type>hyperlink</type>
+            </link>
+            <number>1234</number>
+            <type>route</type>
+            <extensions>
+            <ext-1>value1</ext-1>
+            </extensions>
+            <wpt lat="14.64736838389662" lon="7.93212890625">
+            <ele>10.0</ele>
+            <time>2022-09-24T15:04:00+03:00</time>
+            <magvar>3.0</magvar>
+            <geoidheight>45.0</geoidheight>
+            <name>test point 1</name>
+            <cmt>comment 1</cmt>
+            <desc>description of point 1</desc>
+            <src>source 1</src>
+            <link href="http://link-to.site.href">
+            <text>text</text>
+            <type>hyperlink</type>
+            </link>
+            <link href="http://link2-to.site.href">
+            <text>text2</text>
+            <type>hyperlink2</type>
+            </link>
+            <sym>sym 1</sym>
+            <type>type 1</type>
+            <fix>dgps</fix>
+            <sat>1</sat>
+            <hdop>55.0</hdop>
+            <vdop>66.0</vdop>
+            <pdop>77.0</pdop>
+            <ageofgpsdata>44</ageofgpsdata>
+            <dgpsid>88</dgpsid>
+            <extensions>
+            <extension1 first="second" third="fours"></extension1>
+            <extension2 aa="bb" cc="dd"></extension2>
+            </extensions>
+            </wpt>
+            </rte>
+            <trk>
+            <name>track 1</name>
+            <cmt>comment track 1</cmt>
+            <desc>desc track 1</desc>
+            <src>src track 1</src>
+            <number>1234</number>
+            <type>type 1</type>
+            <trkseg>
+            <trkpt lat="14.64736838389662" lon="7.93212890625">
+            <ele>10.0</ele>
+            <time>2022-09-24T15:04:00+03:00</time>
+            <magvar>3.0</magvar>
+            <geoidheight>45.0</geoidheight>
+            <name>test point 1</name>
+            <cmt>comment 1</cmt>
+            <desc>description of point 1</desc>
+            <src>source 1</src>
+            <link href="http://link-to.site.href">
+            <text>text</text>
+            <type>hyperlink</type>
+            </link>
+            <link href="http://link2-to.site.href">
+            <text>text2</text>
+            <type>hyperlink2</type>
+            </link>
+            <sym>sym 1</sym>
+            <type>type 1</type>
+            <fix>dgps</fix>
+            <sat>1</sat>
+            <hdop>55.0</hdop>
+            <vdop>66.0</vdop>
+            <pdop>77.0</pdop>
+            <ageofgpsdata>44</ageofgpsdata>
+            <dgpsid>88</dgpsid>
+            <extensions>
+            <extension1 first="second" third="fours"></extension1>
+            <extension2 aa="bb" cc="dd"></extension2>
+            </extensions>
+            </trkpt>
+            </trkseg>
+            </trk>
+            </gpx>
+            """.trim()
+                .lineSequence()
+                .map {
+                    it.trim()
+                }
+                .joinToString("\n"),
+            gpxType.toXmlString(clock)
+        )
     }
 }
\ No newline at end of file