core: fix source line number parsing and saving

jadx-core/src/test/java/jadx/tests/internal/debuginfo/TestLineNumbers2.java

@@ -0,0 +1,47 @@
+package jadx.tests.internal.debuginfo;
+
+import jadx.api.InternalJadxTest;
+import jadx.core.codegen.CodeWriter;
+import jadx.core.dex.nodes.ClassNode;
+
+import java.lang.ref.WeakReference;
+import java.util.Map;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class TestLineNumbers2 extends InternalJadxTest {
+
+	public static class TestCls {
+		private WeakReference<TestCls> f;
+
+		public TestCls(TestCls s) {
+		}
+
+		TestCls test(TestCls s) {
+			TestCls store = f != null ? f.get() : null;
+			if (store == null) {
+				store = new TestCls(s);
+				f = new WeakReference<TestCls>(store);
+			}
+			return store;
+		}
+
+		public Object test2() {
+			return new Object();
+		}
+	}
+
+	@Test
+	public void test() {
+		ClassNode cls = getClassNode(TestCls.class);
+		CodeWriter codeWriter = cls.getCode();
+		String code = codeWriter.toString();
+		System.out.println(code);
+
+		Map<Integer, Integer> lineMapping = codeWriter.getLineMapping();
+		assertEquals("{8=18, 11=22, 13=23, 14=24, 15=28, 17=25, 18=26, 19=28, 22=31, 23=32}",
+				lineMapping.toString());
+	}
+}