Fix test: also inject timezone to avoid relying on the system timezone.

libraries/dateformatter/src/main/kotlin/io/element/android/libraries/dateformatter/di/DateFormatterModule.kt

@@ -21,6 +21,7 @@ import dagger.Module
 import dagger.Provides
 import io.element.android.libraries.di.AppScope
 import kotlinx.datetime.Clock
+import kotlinx.datetime.TimeZone
 import java.util.*
 
 @Module
@@ -31,4 +32,7 @@ object DateFormatterModule {
 
     @Provides
     fun providesLocale(): Locale = Locale.getDefault()
+
+    @Provides
+    fun providesTimezone(): TimeZone = TimeZone.currentSystemDefault()
 }

libraries/dateformatter/src/main/kotlin/io/element/android/libraries/dateformatter/impl/DefaultLastMessageFormatter.kt

@@ -39,6 +39,7 @@ import kotlin.math.absoluteValue
 class DefaultLastMessageFormatter @Inject constructor(
     private val clock: Clock,
     private val locale: Locale,
+    private val timezone: TimeZone,
 ) : LastMessageFormatter {
     private val onlyTimeFormatter: DateTimeFormatter by lazy {
         val pattern = DateFormat.getBestDateTimePattern(locale, "HH:mm") ?: "HH:mm"
@@ -59,8 +60,8 @@ class DefaultLastMessageFormatter @Inject constructor(
         if (timestamp == null) return ""
         val now: Instant = clock.now()
         val tsInstant = Instant.fromEpochMilliseconds(timestamp)
-        val nowDateTime = now.toLocalDateTime(TimeZone.currentSystemDefault())
-        val tsDateTime = tsInstant.toLocalDateTime(TimeZone.currentSystemDefault())
+        val nowDateTime = now.toLocalDateTime(timezone)
+        val tsDateTime = tsInstant.toLocalDateTime(timezone)
         val isSameDay = nowDateTime.date == tsDateTime.date
         return when {
             isSameDay -> {
@@ -80,7 +81,7 @@ class DefaultLastMessageFormatter @Inject constructor(
         return if (period.years.absoluteValue >= 1) {
             formatDateWithYear(date)
         } else if (period.days.absoluteValue < 2 && period.months.absoluteValue < 1) {
-            getRelativeDay(date.toInstant(TimeZone.currentSystemDefault()).toEpochMilliseconds())
+            getRelativeDay(date.toInstant(timezone).toEpochMilliseconds())
         } else {
             formatDateWithMonth(date)
         }

libraries/dateformatter/src/test/kotlin/io/element/android/libraries/dateformatter/impl/DefaultLastMessageFormatterTest.kt

@@ -19,6 +19,7 @@ package io.element.android.libraries.dateformatter.impl
 import com.google.common.truth.Truth.assertThat
 import io.element.android.libraries.dateformatter.LastMessageFormatter
 import kotlinx.datetime.Instant
+import kotlinx.datetime.TimeZone
 import org.junit.Test
 import java.util.Locale
 
@@ -43,7 +44,7 @@ class DefaultLastMessageFormatterTest {
         val now = "1980-04-06T18:35:24.00Z"
         val dat = "1980-04-06T18:35:24.00Z"
         val formatter = createFormatter(now)
-        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("20:35")
+        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("18:35")
     }
 
     @Test
@@ -51,7 +52,7 @@ class DefaultLastMessageFormatterTest {
         val now = "1980-04-06T18:35:24.00Z"
         val dat = "1980-04-06T18:35:23.00Z"
         val formatter = createFormatter(now)
-        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("20:35")
+        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("18:35")
     }
 
     @Test
@@ -59,7 +60,7 @@ class DefaultLastMessageFormatterTest {
         val now = "1980-04-06T18:35:24.00Z"
         val dat = "1980-04-06T18:34:24.00Z"
         val formatter = createFormatter(now)
-        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("20:34")
+        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("18:34")
     }
 
     @Test
@@ -67,7 +68,7 @@ class DefaultLastMessageFormatterTest {
         val now = "1980-04-06T18:35:24.00Z"
         val dat = "1980-04-06T17:35:24.00Z"
         val formatter = createFormatter(now)
-        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("19:35")
+        assertThat(formatter.format(Instant.parse(dat).toEpochMilliseconds())).isEqualTo("17:35")
     }
 
     @Test
@@ -100,6 +101,6 @@ class DefaultLastMessageFormatterTest {
      */
     private fun createFormatter(@Suppress("SameParameterValue") currentDate: String): LastMessageFormatter {
         val clock = FakeClock().also { it.givenInstant(Instant.parse(currentDate)) }
-        return DefaultLastMessageFormatter(clock, Locale.US)
+        return DefaultLastMessageFormatter(clock, Locale.US, TimeZone.UTC)
     }
 }