Some tidying up, name changes and clarifications. I went with "defaultValue"

rather than "missingVariableValue" because the value is used any time a
variable resolves to null, not necessarily just when it is missing. If you
have a context like:

new Object() {
   String foo = null;
}

and reference {{foo}} in your template, foo is not missing, per se, but the
default value will still be used for it.

src/test/java/com/samskivert/mustache/MustacheTest.java

@@ -153,12 +153,12 @@ public class MustacheTest
                      execute(context("a", "<b>")));
     }
 
-    @Test(expected = MustacheParseException.class)
+    @Test(expected=MustacheParseException.class)
     public void testDanglingTag () {
         Mustache.compiler().escapeHTML(true).compile("{{a").execute(context("a", "<b>"));
     }
 
-    @Test(expected = MustacheParseException.class)
+    @Test(expected=MustacheParseException.class)
     public void testInvalidUnescapeHTML () {
         Mustache.compiler().escapeHTML(true).compile("{{{a}}").execute(context("a", "<b>"));
     }
@@ -276,7 +276,7 @@ public class MustacheTest
         assertEquals(":bar:", result);
     }
 
-    @Test(expected = MustacheException.class)
+    @Test(expected=MustacheException.class)
     public void testStandardsModeWithNoParentContextSearching () {
         String tmpl = "{{#parent}}foo{{parentProperty}}bar{{/parent}}";
         String result = Mustache.compiler().standardsMode(true).compile(tmpl).
@@ -284,25 +284,19 @@ public class MustacheTest
                             "parentProperty", "bar"));
     }
 
-    @Test(expected = MustacheException.class)
+    @Test(expected=MustacheException.class)
     public void testMissingValue () {
-        String tmpl = "{{ missing }} {{ notmissing }}";
-        Mustache.compiler().compile(tmpl).
-            execute(Collections.singletonMap("notmissing", "bar"));
+        test("n/a", "{{missing}} {{notmissing}}", context("notmissing", "bar"));
     }
 
     @Test public void testMissingValueWithDefault () {
-        String tmpl = "{{ missing }}{{ notmissing }}";
-        String result = Mustache.compiler().missingVariableValue("").compile(tmpl).
-            execute(Collections.singletonMap("notmissing", "bar"));
-        assertEquals("bar", result);
+        test(Mustache.compiler().defaultValue(""),
+             "bar", "{{missing}}{{notmissing}}", context("notmissing", "bar"));
     }
 
     @Test public void testMissingValueWithDefaultNonEmptyString () {
-        String tmpl = "{{ missing }}{{ notmissing }}";
-        String result = Mustache.compiler().missingVariableValue("foo").compile(tmpl).
-            execute(Collections.singletonMap("notmissing", "bar"));
-        assertEquals("foobar", result);
+        test(Mustache.compiler().defaultValue("foo"),
+             "foobar", "{{missing}}{{notmissing}}", context("notmissing", "bar"));
     }
 
     protected void test (Mustache.Compiler compiler, String expected, String template, Object ctx)