Added support for obtaining variable values from fields and methods. Added a

template-local variable fetching cache that avoids reresolving the source of a
variable when it remains monomorphic (e.g. it's always a field of class
Foo.class or always a method named getFoo(), etc.).

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

@@ -17,57 +17,98 @@ import static org.junit.Assert.*;
 public class MustacheTest
 {
     @Test public void testSimpleVariable () {
-        test("bar", "{{foo}}", "foo", "bar");
+        test("bar", "{{foo}}", context("foo", "bar"));
+    }
+
+    @Test public void testFieldVariable () {
+        test("bar", "{{foo}}", new Object() {
+            String foo = "bar";
+        });
+    }
+
+    @Test public void testMethodVariable () {
+        test("bar", "{{foo}}", new Object() {
+            String foo () { return "bar"; }
+        });
+    }
+
+    @Test public void testPropertyVariable () {
+        test("bar", "{{foo}}", new Object() {
+            String getFoo () { return "bar"; }
+        });
+    }
+
+    @Test public void testCallSiteReuse () {
+        Template tmpl = Mustache.compile("{{foo}}");
+        Object ctx = new Object() {
+            String getFoo () { return "bar"; }
+        };
+        for (int ii = 0; ii < 50; ii++) {
+            assertEquals("bar", tmpl.execute(ctx));
+        }
+    }
+
+    @Test public void testCallSiteChange () {
+        Template tmpl = Mustache.compile("{{foo}}");
+        assertEquals("bar", tmpl.execute(new Object() {
+            String getFoo () { return "bar"; }
+        }));
+        assertEquals("bar", tmpl.execute(new Object() {
+            String foo = "bar";
+        }));
     }
 
     @Test public void testOneShotSection () {
-        test("baz", "{{#foo}}{{bar}}{{/foo}}", "foo", context("bar", "baz"));
+        test("baz", "{{#foo}}{{bar}}{{/foo}}", context("foo", context("bar", "baz")));
     }
 
     @Test public void testListSection () {
-        test("bazbif", "{{#foo}}{{bar}}{{/foo}}", "foo",
-             Arrays.asList(context("bar", "baz"), context("bar", "bif")));
+        test("bazbif", "{{#foo}}{{bar}}{{/foo}}", context(
+                 "foo", Arrays.asList(context("bar", "baz"), context("bar", "bif"))));
     }
 
     @Test public void testArraySection () {
-        test("bazbif", "{{#foo}}{{bar}}{{/foo}}", "foo",
-             new Object[] { context("bar", "baz"), context("bar", "bif") });
+        test("bazbif", "{{#foo}}{{bar}}{{/foo}}",
+             context("foo", new Object[] {
+                     context("bar", "baz"), context("bar", "bif") }));
     }
 
     @Test public void testIteratorSection () {
-        test("bazbif", "{{#foo}}{{bar}}{{/foo}}", "foo",
-             Arrays.asList(context("bar", "baz"), context("bar", "bif")).iterator());
+        test("bazbif", "{{#foo}}{{bar}}{{/foo}}",
+             context("foo", Arrays.asList(context("bar", "baz"),
+                                          context("bar", "bif")).iterator()));
     }
 
     @Test public void testEmptyListSection () {
-        test("", "{{#foo}}{{bar}}{{/foo}}", "foo", Collections.emptyList());
+        test("", "{{#foo}}{{bar}}{{/foo}}", context("foo", Collections.emptyList()));
     }
 
     @Test public void testEmptyArraySection () {
-        test("", "{{#foo}}{{bar}}{{/foo}}", "foo", new Object[0]);
+        test("", "{{#foo}}{{bar}}{{/foo}}", context("foo", new Object[0]));
     }
 
     @Test public void testEmptyIteratorSection () {
-        test("", "{{#foo}}{{bar}}{{/foo}}", "foo", Collections.emptyList().iterator());
+        test("", "{{#foo}}{{bar}}{{/foo}}", context("foo", Collections.emptyList().iterator()));
     }
 
     @Test public void testFalseSection () {
-        test("", "{{#foo}}{{bar}}{{/foo}}", "foo", false);
+        test("", "{{#foo}}{{bar}}{{/foo}}", context("foo", false));
     }
 
     @Test public void testNestedListSection () {
-        test("1234", "{{#a}}{{#b}}{{c}}{{/b}}{{#d}}{{e}}{{/d}}{{/a}}", "a",
-             new Object[] { context("b", new Object[] { context("c", "1"), context("c", "2") }),
-                            context("d", new Object[] { context("e", "3"), context("e", "4") }) });
+        test("1234", "{{#a}}{{#b}}{{c}}{{/b}}{{#d}}{{e}}{{/d}}{{/a}}",
+             context("a", new Object[] {
+                     context("b", new Object[] { context("c", "1"), context("c", "2") }),
+                     context("d", new Object[] { context("e", "3"), context("e", "4") }) }));
     }
 
     @Test public void testComment () {
-        test("foobar", "foo{{! nothing to see here}}bar");
+        test("foobar", "foo{{! nothing to see here}}bar", new Object());
     }
 
-    protected void test (String expected, String template, Object... data)
+    protected void test (String expected, String template, Object ctx)
     {
-        assertEquals(expected, Mustache.compile(template).execute(context(data)));
+        assertEquals(expected, Mustache.compile(template).execute(ctx));
     }
 
     protected static Object context (Object... data)