Commands can be parsed, in a very limited way.

src/main/test/net/minecraft/commands/arguments/IntegerArgumentTypeTest.java

@@ -0,0 +1,48 @@
+package net.minecraft.commands.arguments;
+
+import net.minecraft.commands.exceptions.IllegalCommandArgumentException;
+import org.junit.Before;
+import org.junit.Test;
+
+import static net.minecraft.commands.arguments.IntegerArgumentType.integer;
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertThat;
+
+public class IntegerArgumentTypeTest {
+    IntegerArgumentType type;
+
+    @Before
+    public void setUp() throws Exception {
+        type = integer(-100, 100);
+    }
+
+    @Test
+    public void testParse() throws Exception {
+        assertThat(type.parse("50"), is(50));
+    }
+
+    @Test(expected = IllegalCommandArgumentException.class)
+    public void testParseInvalid() throws Exception {
+        type.parse("fifty");
+    }
+
+    @Test(expected = IllegalCommandArgumentException.class)
+    public void testParseTooLow() throws Exception {
+        type.parse("-101");
+    }
+
+    @Test
+    public void testParseLowerLimit() throws Exception {
+        assertThat(type.parse("-100"), is(-100));
+    }
+
+    @Test(expected = IllegalCommandArgumentException.class)
+    public void testParseTooHigh() throws Exception {
+        type.parse("101");
+    }
+
+    @Test
+    public void testParseHigherLimit() throws Exception {
+        assertThat(type.parse("100"), is(100));
+    }
+}

src/main/test/net/minecraft/commands/builder/RequiredArgumentBuilderTest.java

@@ -13,8 +13,8 @@ import static org.hamcrest.Matchers.is;
 import static org.junit.Assert.assertThat;
 
 public class RequiredArgumentBuilderTest {
-    @Mock CommandArgumentType type;
-    RequiredArgumentBuilder builder;
+    @Mock CommandArgumentType<Integer> type;
+    RequiredArgumentBuilder<Integer> builder;
 
     @Before
     public void setUp() throws Exception {
@@ -23,7 +23,7 @@ public class RequiredArgumentBuilderTest {
 
     @Test
     public void testBuild() throws Exception {
-        ArgumentCommandNode node = builder.build();
+        ArgumentCommandNode<Integer> node = builder.build();
 
         assertThat(node.getName(), is("foo"));
         assertThat(node.getType(), is(type));

src/main/test/net/minecraft/commands/tree/ArgumentCommandNodeTest.java

@@ -0,0 +1,27 @@
+package net.minecraft.commands.tree;
+
+import net.minecraft.commands.exceptions.IllegalCommandArgumentException;
+import org.junit.Before;
+import org.junit.Test;
+
+import static net.minecraft.commands.arguments.IntegerArgumentType.integer;
+import static net.minecraft.commands.builder.RequiredArgumentBuilder.argument;
+
+public class ArgumentCommandNodeTest {
+    ArgumentCommandNode node;
+
+    @Before
+    public void setUp() throws Exception {
+        node = argument("foo", integer()).build();
+    }
+
+    @Test
+    public void testParse() throws Exception {
+        node.parse("123");
+    }
+
+    @Test(expected = IllegalCommandArgumentException.class)
+    public void testParseInvalid() throws Exception {
+        node.parse("bar");
+    }
+}

src/main/test/net/minecraft/commands/tree/LiteralCommandNodeTest.java

@@ -0,0 +1,26 @@
+package net.minecraft.commands.tree;
+
+import net.minecraft.commands.exceptions.IllegalCommandArgumentException;
+import org.junit.Before;
+import org.junit.Test;
+
+import static net.minecraft.commands.builder.CommandBuilder.command;
+
+public class LiteralCommandNodeTest {
+    LiteralCommandNode node;
+
+    @Before
+    public void setUp() throws Exception {
+        node = command("foo").build();
+    }
+
+    @Test
+    public void testParse() throws Exception {
+        node.parse("foo");
+    }
+
+    @Test(expected = IllegalCommandArgumentException.class)
+    public void testParseInvalid() throws Exception {
+        node.parse("bar");
+    }
+}