Merge pull request #27149 from marckchr

* pr/27149:
  Polish "Fix duration to microseconds conversion"
  Fix duration to microseconds conversion

Closes gh-27149

Author: snicoll

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/convert/DurationStyle.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -183,7 +183,7 @@ enum Unit {
 		/**
 		 * Microseconds.
 		 */
-		MICROS(ChronoUnit.MICROS, "us", (duration) -> duration.toMillis() * 1000L),
+		MICROS(ChronoUnit.MICROS, "us", (duration) -> duration.toNanos() / 1000L),
 
 		/**
 		 * Milliseconds.

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/convert/DurationStyleTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -231,9 +231,15 @@ void printSimpleWithoutUnitShouldPrintInMs() {
 	}
 
 	@Test
-	void printSimpleWithUnitShouldPrintInUnit() {
+	void printSimpleWithSecondsUnitShouldPrintInUnit() {
 		Duration duration = Duration.ofMillis(1000);
 		assertThat(DurationStyle.SIMPLE.print(duration, ChronoUnit.SECONDS)).isEqualTo("1s");
 	}
 
+	@Test
+	void printSimpleWithMicrosUnitShouldPrintInUnit() {
+		Duration duration = Duration.ofNanos(2000);
+		assertThat(DurationStyle.SIMPLE.print(duration, ChronoUnit.MICROS)).isEqualTo("2us");
+	}
+
 }