diff --git a/libcore/luni/src/test/java/tests/api/java/util/CalendarTest.java b/libcore/luni/src/test/java/tests/api/java/util/CalendarTest.java
index cc0f91a..4ffe2c6 100644
--- a/libcore/luni/src/test/java/tests/api/java/util/CalendarTest.java
+++ b/libcore/luni/src/test/java/tests/api/java/util/CalendarTest.java
@@ -983,11 +983,12 @@
             // locale dependent test, bug 1943269
             return;
         }
+        Locale.setDefault(Locale.US);
         Calendar cal = Calendar.getInstance();
-        assertTrue(cal.getMinimalDaysInFirstWeek()==1);
+        assertEquals(1, cal.getMinimalDaysInFirstWeek());
         Locale.setDefault(Locale.FRANCE);
         cal = Calendar.getInstance();
-        assertTrue(cal.getMinimalDaysInFirstWeek()==4);
+        assertEquals(4, cal.getMinimalDaysInFirstWeek());
         Locale.setDefault(Locale.US);
     }
 
diff --git a/libcore/luni/src/test/java/tests/api/java/util/FormatterTest.java b/libcore/luni/src/test/java/tests/api/java/util/FormatterTest.java
index fb03a34..1b16c93 100644
--- a/libcore/luni/src/test/java/tests/api/java/util/FormatterTest.java
+++ b/libcore/luni/src/test/java/tests/api/java/util/FormatterTest.java
@@ -2101,25 +2101,25 @@
         china.set(Calendar.MILLISECOND, 609);
 
         final Object[][] lowerCaseGermanTriple = {
-                {0L,                        'a', "Do"},  //$NON-NLS-2$
-                {Long.MAX_VALUE,            'a', "So"},  //$NON-NLS-2$
-                {-1000L,                    'a', "Do"},  //$NON-NLS-2$
-                {new Date(1147327147578L),  'a', "Do"},  //$NON-NLS-2$
-                {paris,                     'a', "Mo"},  //$NON-NLS-2$
-                {china,                     'a', "Mo"},  //$NON-NLS-2$
+                {0L,                        'a', "Do."},  //$NON-NLS-2$
+                {Long.MAX_VALUE,            'a', "So."},  //$NON-NLS-2$
+                {-1000L,                    'a', "Do."},  //$NON-NLS-2$
+                {new Date(1147327147578L),  'a', "Do."},  //$NON-NLS-2$
+                {paris,                     'a', "Mo."},  //$NON-NLS-2$
+                {china,                     'a', "Mo."},  //$NON-NLS-2$
                 {0L,                        'b', "Jan"},  //$NON-NLS-2$
                 {Long.MAX_VALUE,            'b', "Aug"},  //$NON-NLS-2$
                 {-1000L,                    'b', "Jan"},  //$NON-NLS-2$
                 {new Date(1147327147578L),  'b', "Mai"},  //$NON-NLS-2$
                 {paris,                     'b', "Mai"},  //$NON-NLS-2$
                 {china,                     'b', "Mai"},  //$NON-NLS-2$
-                {0L,                        'c', "Do Jan 01 08:00:00 GMT+08:00 1970"},  //$NON-NLS-2$
-                // {Long.MAX_VALUE,            'c', "So Aug 17 15:12:55 GMT+08:00 292278994"},  //$NON-NLS-2$
-                {Long.MAX_VALUE,            'c', "So Aug 17 15:18:47 GMT+08:00 292278994"},  //$NON-NLS-2$
-                {-1000L,                    'c', "Do Jan 01 07:59:59 GMT+08:00 1970"},  //$NON-NLS-2$
-                {new Date(1147327147578L),  'c', "Do Mai 11 13:59:07 GMT+08:00 2006"},  //$NON-NLS-2$
-                {paris,                     'c', "Mo Mai 08 12:00:00 MESZ 2006"},  //$NON-NLS-2$
-                {china,                     'c', "Mo Mai 08 12:00:00 GMT-08:00 2006"},  //$NON-NLS-2$
+                {0L,                        'c', "Do. Jan 01 08:00:00 GMT+08:00 1970"},  //$NON-NLS-2$
+                // {Long.MAX_VALUE,            'c', "So. Aug 17 15:12:55 GMT+08:00 292278994"},  //$NON-NLS-2$
+                {Long.MAX_VALUE,            'c', "So. Aug 17 15:18:47 GMT+08:00 292278994"},  //$NON-NLS-2$
+                {-1000L,                    'c', "Do. Jan 01 07:59:59 GMT+08:00 1970"},  //$NON-NLS-2$
+                {new Date(1147327147578L),  'c', "Do. Mai 11 13:59:07 GMT+08:00 2006"},  //$NON-NLS-2$
+                {paris,                     'c', "Mo. Mai 08 12:00:00 MESZ 2006"},  //$NON-NLS-2$
+                {china,                     'c', "Mo. Mai 08 12:00:00 GMT-08:00 2006"},  //$NON-NLS-2$
                 {0L,                        'd', "01"},  //$NON-NLS-2$
                 {Long.MAX_VALUE,            'd', "17"},  //$NON-NLS-2$
                 {-1000L,                    'd', "01"},  //$NON-NLS-2$
diff --git a/libcore/support/src/test/java/tests/util/TestEnvironment.java b/libcore/support/src/test/java/tests/util/TestEnvironment.java
index 69a87c2..088e624 100644
--- a/libcore/support/src/test/java/tests/util/TestEnvironment.java
+++ b/libcore/support/src/test/java/tests/util/TestEnvironment.java
@@ -73,12 +73,21 @@
         TimeZone.setDefault(TimeZone.getTimeZone("America/Los_Angeles"));
     }
 
-    private static void resetSystemProperties() {
-        String tmpDir = System.getProperty("java.io.tmpdir");
-        if (tmpDir == null) {
-            throw new IllegalStateException("Test execution requires the"
-                    + " system property java.io.tmpdir to be set.");
+    private static String getExistingSystemProperty(String name) {
+        String result = System.getProperty(name);
+        if (result == null) {
+            throw new AssertionError("Tests require the '" + name + "' system property");
         }
+        return result;
+    }
+
+    private static void resetSystemProperties() {
+        // There are two system properties we can't live without.
+        // 1. We need somewhere writable to stash our stuff.
+        String tmpDir = getExistingSystemProperty("java.io.tmpdir");
+        // 2. We need to know who we are, specifically "am I root?" because that affects what
+        // the OS lets us do, and that affects test expectations.
+        String userName = getExistingSystemProperty("user.name");
 
         Properties p = new Properties();
 
@@ -129,7 +138,7 @@
         p.put("line.separator", "\n");
         p.put("path.separator", ":");
         p.put("user.language", "en");
-        p.put("user.name", "");
+        p.put("user.name", userName);
         p.put("user.region", "US");
 
         System.setProperties(p);