Fix capitalization of single character strings (#9880)

2 files changed, 2 insertions, 1 deletions

diff --git a/shared/src/main/java/com/vaadin/shared/util/SharedUtil.java b/shared/src/main/java/com/vaadin/shared/util/SharedUtil.java
index eaf8729a5e..974c45ae02 100644
--- a/shared/src/main/java/com/vaadin/shared/util/SharedUtil.java
+++ b/shared/src/main/java/com/vaadin/shared/util/SharedUtil.java
@@ -199,7 +199,7 @@ public class SharedUtil implements Serializable {
         }
 
         if (string.length() <= 1) {
-            return string.toUpperCase();
+            return string.toUpperCase(Locale.ENGLISH);
         }
 
         return string.substring(0, 1).toUpperCase(Locale.ENGLISH)
diff --git a/shared/src/test/java/com/vaadin/shared/util/SharedUtilTest.java b/shared/src/test/java/com/vaadin/shared/util/SharedUtilTest.java
index 791637e1b1..b468093da1 100644
--- a/shared/src/test/java/com/vaadin/shared/util/SharedUtilTest.java
+++ b/shared/src/test/java/com/vaadin/shared/util/SharedUtilTest.java
@@ -113,6 +113,7 @@ public class SharedUtilTest {
         try {
             Locale.setDefault(new Locale("tr", "TR"));
             Assert.assertEquals("Integer", SharedUtil.capitalize("integer"));
+            Assert.assertEquals("I", SharedUtil.capitalize("i"));
         } finally {
             Locale.setDefault(defaultLocale);
         }