Add CloseShieldInputStream tests

Author: garydgregory

src/test/java/org/apache/commons/io/input/CloseShieldInputStreamTest.java

@@ -24,6 +24,7 @@
 import java.io.IOException;
 import java.io.InputStream;
 
+import org.apache.commons.io.IOUtils;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
@@ -52,6 +53,23 @@ public void close() {
         closed = false;
     }
 
+    @Test
+    public void testAvailableAfterCose() throws Exception {
+        InputStream shadow;
+        try (InputStream in = CloseShieldInputStream.wrap(byteArrayInputStream)) {
+            assertEquals(3, in.available());
+            shadow = in;
+        }
+        assertEquals(0, shadow.available());
+    }
+
+    @Test
+    public void testAvailableAfterOpen() throws Exception {
+        try (InputStream in = CloseShieldInputStream.wrap(byteArrayInputStream)) {
+            assertEquals(3, in.available());
+        }
+    }
+
     @Test
     public void testClose() throws IOException {
         shielded = CloseShieldInputStream.wrap(byteArrayInputStream);
@@ -61,6 +79,17 @@ public void testClose() throws IOException {
         assertEquals(data[0], byteArrayInputStream.read(), "read()");
     }
 
+
+    @Test
+    public void testReadAfterCose() throws Exception {
+        InputStream shadow;
+        try (InputStream in = CloseShieldInputStream.wrap(byteArrayInputStream)) {
+            assertEquals(3, in.available());
+            shadow = in;
+        }
+        assertEquals(IOUtils.EOF, shadow.read());
+    }
+
     @Test
     public void testSystemInOnSystemInNo() throws IOException {
         shielded = CloseShieldInputStream.systemIn(byteArrayInputStream);