GT-3333 more better tests & fix padding logic

Add ArrayStringable tests and fix an error in rounding length code

Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/data/StringDataInstance.java

@@ -509,7 +509,7 @@ public class StringDataInstance {
 
 	private byte[] getBytesFromMemBuff(MemBuffer memBuffer, int copyLen) {
 		// round copyLen down to multiple of paddedCharSize
-		copyLen &= ~(paddedCharSize - 1);
+		copyLen = (copyLen / paddedCharSize) * paddedCharSize;
 
 		byte[] bytes = new byte[copyLen];
 		if (memBuffer.getBytes(bytes, 0) != bytes.length) {

Ghidra/Framework/SoftwareModeling/src/test/java/ghidra/program/model/data/ArrayStringableTest.java

@@ -0,0 +1,112 @@
+/* ###
+ * IP: GHIDRA
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package ghidra.program.model.data;
+
+import static org.junit.Assert.*;
+
+import org.junit.Test;
+
+import generic.test.AbstractGTest;
+import ghidra.program.model.address.AddressSpace;
+import ghidra.program.model.address.GenericAddressSpace;
+import ghidra.program.model.mem.ByteMemBufferImpl;
+
+public class ArrayStringableTest extends AbstractGTest {
+	private ByteMemBufferImpl mb(boolean isBE, int... values) {
+		byte[] bytes = new byte[values.length];
+		for (int i = 0; i < values.length; i++) {
+			bytes[i] = (byte) values[i];
+		}
+		GenericAddressSpace gas = new GenericAddressSpace("test", 32, AddressSpace.TYPE_RAM, 1);
+		return new ByteMemBufferImpl(gas.getAddress(0), bytes, isBE);
+	}
+
+	private SettingsBuilder newset() {
+		return new SettingsBuilder();
+	}
+
+	private static class DataOrgDTM extends TestDummyDataTypeManager {
+		private DataOrganization dataOrg;
+
+		public DataOrgDTM(int charSize) {
+			DataOrganizationImpl dataOrgImpl = DataOrganizationImpl.getDefaultOrganization(null);
+			dataOrgImpl.setCharSize(charSize);
+
+			this.dataOrg = dataOrgImpl;
+		}
+
+		@Override
+		public DataOrganization getDataOrganization() {
+			return dataOrg;
+		}
+	}
+
+	private Array mkArray(DataTypeManager dtm, int count) {
+		CharDataType charDT = new CharDataType(dtm);
+		Array arrayDT = new ArrayDataType(charDT, count, charDT.getLength(), dtm);
+
+		return arrayDT;
+	}
+
+
+	private Array array10char1 = mkArray(new DataOrgDTM(1), 10);
+	private Array array10char2 = mkArray(new DataOrgDTM(2), 10);
+	private Array array6char4 = mkArray(new DataOrgDTM(4), 6);
+	private Array array10char5 = mkArray(new DataOrgDTM(5), 3);
+
+	//-------------------------------------------------------------------------------------
+	// get string rep of an array of various sized character elements
+	//-------------------------------------------------------------------------------------
+	@Test
+	public void testGetRep_1bytechar() {
+		// because the char size is 1, default charset will be us-ascii, which matches character element size
+		ByteMemBufferImpl buf = mb(false, 'h', 'e', 'l', 'l', 'o', 0, 'x', 'y', 0, 0);
+
+		assertEquals("\"hello\"",
+			array10char1.getRepresentation(buf, newset(), array10char1.getLength()));
+	}
+
+	@Test
+	public void testGetRep_2bytechar() {
+		// because char size is 2, default charset will be utf-16, which matches character element size
+		ByteMemBufferImpl buf =
+			mb(false, 'h', 0, 'e', 0, 'l', 0, 'l', 0, 'o', 0, 0, 0, 'x', 'y', 0, 0, 0, 0, 0, 0);
+
+		assertEquals("u\"hello\"",
+			array10char2.getRepresentation(buf, newset(), array10char2.getLength()));
+	}
+
+	@Test
+	public void testGetRep_4bytechar() {
+		// because char size is 4, default charset will be utf-32, which matches character element size
+		ByteMemBufferImpl buf = mb(false, 'h', 0, 0, 0, 'e', 0, 0, 0, 'l', 0, 0, 0, 'l', 0, 0, 0,
+			'o', 0, 0, 0, 0, 0, 0, 0, 'x', 'y', 0, 0, 0, 0, 0, 0);
+
+		assertEquals("U\"hello\"",
+			array6char4.getRepresentation(buf, newset(), array6char4.getLength()));
+	}
+
+	@Test
+	public void testGetRep_5bytechar() {
+		// because the char size isn't normal, charset will default to us-ascii, which does not match
+		// the element size of the array, triggering padding-removal in the stringdatainstance code.
+		ByteMemBufferImpl buf =
+			mb(false, 'h', 'x', 'x', 'x', 'x', 'e', 'x', 'x', 'x', 'x', 0, 0, 0, 0, 0);
+
+		assertEquals("\"he\"",
+			array10char5.getRepresentation(buf, newset(), array10char5.getLength()));
+	}
+}