1 files changed, 94 insertions, 0 deletions
diff --git a/src/test/model/asn1/ASN1LengthTest.java b/src/test/model/asn1/ASN1LengthTest.java
new file mode 100644
index 0000000..44aed8e
--- /dev/null
+++ b/src/test/model/asn1/ASN1LengthTest.java
@@ -0,0 +1,94 @@
+package model.asn1;
+
+import model.asn1.exceptions.ParseException;
+import model.asn1.parsing.BytesReader;
+import model.asn1.parsing.BytesReaderTest;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class ASN1LengthTest {
+    @Test
+    void testConstructor() {
+        assertEquals(0, new ASN1Length(0).getLength());
+        assertEquals(1, new ASN1Length(1).getLength());
+    }
+
+    @Test
+    void testParse() throws Exception { // TODO: Exception
+        BytesReader reader = new BytesReader(new Byte[]{ 0x0 });
+        assertEquals(0, new ASN1Length(reader).getLength());
+        assertEquals(1, reader.getIndex());
+
+        reader = new BytesReader(new Byte[]{ 0x20 });
+        assertEquals(0x20, new ASN1Length(reader).getLength());
+        assertEquals(1, reader.getIndex());
+
+        reader = new BytesReader(new Byte[]{ -127, 0x30 });
+        assertEquals(0x30, new ASN1Length(reader).getLength());
+        assertEquals(2, reader.getIndex());
+
+        reader = new BytesReader(new Byte[]{ -126, -22, 0x60 });
+        assertEquals(60000, new ASN1Length(reader).getLength());
+        assertEquals(3, reader.getIndex());
+
+        reader = new BytesReader(new Byte[]{ -127, 127 });
+        assertEquals(127, new ASN1Length(reader).getLength());
+        assertEquals(2, reader.getIndex());
+
+        reader = new BytesReader(new Byte[]{ -124, 1, 1, 1, 1 });
+        assertEquals(16843009, new ASN1Length(reader).getLength());
+        assertEquals(5, reader.getIndex());
+
+        reader = new BytesReader(new Byte[]{ -127, -97 });
+        assertEquals(159, new ASN1Length(reader).getLength());
+        assertEquals(2, reader.getIndex());
+    }
+
+    @Test
+    void testParseFail() throws ParseException {
+        // First byte 0b10000000
+        assertThrows(ParseException.class, () ->
+                new ASN1Length(new BytesReader(new Byte[]{ -128 }))
+        );
+
+        // First byte 0b11111111
+        assertThrows(ParseException.class, () ->
+                new ASN1Length(new BytesReader(new Byte[]{ -1 }))
+        );
+
+        // Multibyte, requested 2 bytes but have none.
+        assertThrows(ParseException.class, () ->
+                new ASN1Length(new BytesReader(new Byte[]{ -126 }))
+        );
+
+        // Multibyte, requested 2 bytes but have one.
+        assertThrows(ParseException.class, () ->
+                new ASN1Length(new BytesReader(new Byte[]{ -126, 0x1 }))
+        );
+
+        // But this one should work (0b01111111)
+        new ASN1Length(new BytesReader(new Byte[]{ -127, 127 }));
+
+        // Multibyte, too long.
+        assertThrows(ParseException.class, () ->
+                new ASN1Length(new BytesReader(new Byte[]{ -124, -1, -1, -1, -1 }))
+        );
+        // But this one should work, except for it is too large
+        new ASN1Length(new BytesReader(new Byte[]{ -125, -1, -1, -1 }));
+    }
+
+    @Test
+    void testEncode() {
+        // Short form
+        assertArrayEquals(new Byte[]{ 0x0 }, new ASN1Length(0).encodeDER());
+        assertArrayEquals(new Byte[]{ 0x1 }, new ASN1Length(1).encodeDER());
+        assertArrayEquals(new Byte[]{ 127 }, new ASN1Length(127).encodeDER());
+
+        // Long form
+        // 0b10000001, 0b10000000
+        assertArrayEquals(new Byte[]{ -127, -128 }, new ASN1Length(128).encodeDER());
+        // 0b10000010, 0b11111111, 0b11111111
+        assertArrayEquals(new Byte[]{ -126, -1, -1 }, new ASN1Length(65535).encodeDER());
+    }
+}