@@ -0,0 +1,751 @@
+package com.github.dakusui.actionunit.ut.actions;%0A%0Aimport com.github.dakusui.actionunit.Action;%0Aimport org.junit.Test;%0A%0Aimport static com.github.dakusui.actionunit.Actions.nop;%0Aimport static com.github.dakusui.actionunit.Actions.tag;%0Aimport static junit.framework.TestCase.assertFalse;%0A%0Apublic class TagTest %7B%0A  @Test%0A  public void givenNonTagAction$whenEquals$thenFalse() %7B%0A    Action action = tag(0);%0A    assertFalse(action.equals(nop()));%0A  %7D%0A%0A  @Test%0A  public void givenTagActionWithDifferentIndex$whenEquals$thenFalse() %7B%0A    Action action = tag(0);%0A    assertFalse(action.equals(tag(1)));%0A  %7D%0A%0A  @Test(expected = IllegalArgumentException.class)%0A  public void givenNegativeInteger$whenInstantiate$thenIllegalArgumentThrown() %7B%0A    tag(-1);%0A  %7D%0A%7D%0A

Add tests for tag action.