fix: improve type inference for arrays (#837)

jadx-core/src/main/java/jadx/core/dex/visitors/typeinference/TypeUpdate.java

@@ -96,13 +96,13 @@ public final class TypeUpdate {
 		TypeCompareEnum compareResult = comparator.compareTypes(candidateType, currentType);
 		if (arg.isTypeImmutable() && currentType != ArgType.UNKNOWN) {
 			// don't changed type
-			if (compareResult == TypeCompareEnum.CONFLICT) {
-				if (Consts.DEBUG) {
-					LOG.debug("Type rejected for {} due to conflict: candidate={}, current={}", arg, candidateType, currentType);
-				}
-				return REJECT;
+			if (compareResult == TypeCompareEnum.EQUAL) {
+				return SAME;
 			}
-			return SAME;
+			if (Consts.DEBUG) {
+				LOG.debug("Type rejected for {} due to conflict: candidate={}, current={}", arg, candidateType, currentType);
+			}
+			return REJECT;
 		}
 		if (compareResult.isWider() && !updateInfo.getFlags().isAllowWider()) {
 			if (Consts.DEBUG) {
@@ -412,7 +412,7 @@ public final class TypeUpdate {
 			TypeUpdateResult result = updateTypeChecked(updateInfo, putArg, arrayElement);
 			if (result == REJECT) {
 				ArgType putType = putArg.getType();
-				if (putType.isTypeKnown() && putType.isObject()) {
+				if (putType.isTypeKnown() && !putType.isPrimitive()) {
 					TypeCompareEnum compResult = comparator.compareTypes(arrayElement, putType);
 					if (compResult == TypeCompareEnum.WIDER || compResult == TypeCompareEnum.WIDER_BY_GENERIC) {
 						// allow wider result (i.e allow put in Object[] any objects)

jadx-core/src/test/java/jadx/core/dex/visitors/typeinference/TypeCompareTest.java

@@ -15,6 +15,7 @@ import jadx.core.dex.instructions.args.ArgType;
 import jadx.core.dex.nodes.RootNode;
 
 import static jadx.core.dex.instructions.args.ArgType.BOOLEAN;
+import static jadx.core.dex.instructions.args.ArgType.BYTE;
 import static jadx.core.dex.instructions.args.ArgType.CHAR;
 import static jadx.core.dex.instructions.args.ArgType.CLASS;
 import static jadx.core.dex.instructions.args.ArgType.INT;
@@ -77,6 +78,9 @@ public class TypeCompareTest {
 
 		firstIsNarrow(UNKNOWN_ARRAY, OBJECT);
 
+		firstIsNarrow(array(BYTE), OBJECT);
+		firstIsNarrow(array(array(BYTE)), array(OBJECT));
+
 		check(array(OBJECT), array(INT), TypeCompareEnum.CONFLICT);
 
 		ArgType integerType = ArgType.object("java.lang.Integer");

jadx-core/src/test/java/jadx/tests/integration/types/TestTypeResolver11.java

@@ -1,16 +1,19 @@
 package jadx.tests.integration.types;
 
+import java.util.Arrays;
+
 import org.junit.jupiter.api.Test;
 
-import jadx.NotYetImplemented;
 import jadx.tests.api.IntegrationTest;
 
+import static jadx.tests.api.utils.assertj.JadxAssertions.assertThat;
+
 public class TestTypeResolver11 extends IntegrationTest {
 
 	public static class TestCls {
-		public Void test(Object... objArr) {
-			int val = (Integer) objArr[0];
-			String str = (String) objArr[1];
+		public Void test(Object... objects) {
+			int val = (Integer) objects[0];
+			String str = (String) objects[1];
 			call(str, str, val, val);
 			return null;
 		}
@@ -18,21 +21,31 @@ public class TestTypeResolver11 extends IntegrationTest {
 		private void call(String a, String b, int... val) {
 		}
 
+		private boolean test2(String s1, String... args) {
+			String str = Arrays.toString(args);
+			return s1.length() + str.length() > 0;
+		}
+
 		public void check() {
 			test(1, "str");
+			assertThat(test2("1", "2", "34")).isTrue();
 		}
 	}
 
-	@NotYetImplemented("Missing cast")
 	@Test
 	public void test() {
-		getClassNode(TestCls.class);
+		assertThat(getClassNode(TestCls.class))
+				.code()
+				.containsOne("(Integer) objects[0]")
+				.containsOne("String str = (String) objects[1];");
 	}
 
-	@NotYetImplemented("Missing cast")
 	@Test
 	public void testNoDebug() {
 		noDebugInfo();
-		getClassNode(TestCls.class);
+		assertThat(getClassNode(TestCls.class))
+				.code()
+				.containsOne("(Integer) objArr[0]")
+				.containsOne("String str = (String) objArr[1];");
 	}
 }