feat: improve better name algorithm

jadx-core/src/main/java/jadx/core/dex/visitors/rename/SourceFileRename.java

@@ -81,7 +81,7 @@ private static String getBetterName(String currentName, String sourceName, UseSo
 			case ALWAYS:
 				return sourceName;
 			case IF_BETTER:
-				return BetterName.compareAndGet(sourceName, currentName);
+				return BetterName.getBetterClassName(sourceName, currentName);
 			case NEVER:
 				return currentName;
 			default:

jadx-core/src/main/java/jadx/core/utils/BetterName.java

@@ -15,6 +15,78 @@ public class BetterName {
 
 	private static final boolean DEBUG = false;
 
+	private static final double TOLERANCE = 0.001;
+
+	/**
+	 * Compares two class names and returns the "better" one.
+	 * If both names are equally good, {@code firstName} is returned.
+	 */
+	public static String getBetterClassName(String firstName, String secondName) {
+		return getBetterName(firstName, secondName);
+	}
+
+	/**
+	 * Compares two resource names and returns the "better" one.
+	 * If both names are equally good, {@code firstName} is returned.
+	 */
+	public static String getBetterResourceName(String firstName, String secondName) {
+		return getBetterName(firstName, secondName);
+	}
+
+	private static String getBetterName(String firstName, String secondName) {
+		if (Objects.equals(firstName, secondName)) {
+			return firstName;
+		}
+
+		if (StringUtils.isEmpty(firstName) || StringUtils.isEmpty(secondName)) {
+			return StringUtils.notEmpty(firstName)
+					? firstName
+					: secondName;
+		}
+
+		final var firstResult = analyze(firstName);
+		final var secondResult = analyze(secondName);
+
+		if (firstResult.digitCount != 0 || secondResult.digitCount != 0) {
+			final var firstRatio = (float) firstResult.digitCount / firstResult.length;
+			final var secondRatio = (float) secondResult.digitCount / secondResult.length;
+
+			if (Math.abs(secondRatio - firstRatio) >= TOLERANCE) {
+				return firstRatio <= secondRatio
+						? firstName
+						: secondName;
+			}
+		}
+
+		return firstResult.length >= secondResult.length
+				? firstName
+				: secondName;
+	}
+
+	private static AnalyzeResult analyze(String name) {
+		final var result = new AnalyzeResult();
+
+		StringUtils.visitCodePoints(name, cp -> {
+			if (Character.isDigit(cp)) {
+				result.digitCount++;
+			}
+
+			result.length++;
+		});
+
+		return result;
+	}
+
+	private static class AnalyzeResult {
+		private int length;
+		private int digitCount;
+	}
+
+	/**
+	 * @deprecated Use {@link #getBetterClassName(String, String)} or
+	 *             {@link #getBetterResourceName(String, String)} instead.
+	 */
+	@Deprecated
 	public static String compareAndGet(String first, String second) {
 		if (Objects.equals(first, second)) {
 			return first;
@@ -32,6 +104,11 @@ public static String compareAndGet(String first, String second) {
 		return firstBetter ? first : second;
 	}
 
+	/**
+	 * @deprecated This function is an implementation detail of deprecated
+	 *             {@link #compareAndGet(String, String)} and should not be used outside tests.
+	 */
+	@Deprecated
 	public static int calcRating(String str) {
 		int rating = str.length() * 3;
 		rating += differentCharsCount(str) * 20;
@@ -49,6 +126,7 @@ public static int calcRating(String str) {
 		return rating;
 	}
 
+	@Deprecated
 	private static int differentCharsCount(String str) {
 		String lower = str.toLowerCase(Locale.ROOT);
 		Set<Integer> chars = new HashSet<>();

jadx-core/src/main/java/jadx/core/xmlgen/ResTableBinaryParser.java

@@ -490,7 +490,7 @@ private String getResAlias(int resRef, String origKeyName, @Nullable FieldNode c
 	public static String getBetterName(ResourceNameSource nameSource, String resName, String codeName) {
 		switch (nameSource) {
 			case AUTO:
-				return BetterName.compareAndGet(resName, codeName);
+				return BetterName.getBetterResourceName(resName, codeName);
 			case RESOURCES:
 				return resName;
 			case CODE:

jadx-core/src/test/java/jadx/core/utils/TestBetterName.java

@@ -7,12 +7,14 @@
 
 public class TestBetterName {
 
+	@Deprecated
 	@Test
 	public void test() {
 		expectFirst("color_main", "t0");
 		expectFirst("done", "oOo0oO0o");
 	}
 
+	@Deprecated
 	private void expectFirst(String first, String second) {
 		String best = BetterName.compareAndGet(first, second);
 		assertThat(best)

jadx-core/src/test/java/jadx/core/utils/TestGetBetterClassName.java

@@ -0,0 +1,67 @@
+package jadx.core.utils;
+
+import org.assertj.core.api.AbstractStringAssert;
+import org.junit.jupiter.api.Test;
+
+import static jadx.core.utils.BetterName.getBetterClassName;
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class TestGetBetterClassName {
+
+	@Test
+	public void testGoodNamesVsGeneratedAliases() {
+		assertThatBetterClassName("AppCompatButton", "C2404e2").isEqualTo("AppCompatButton");
+		assertThatBetterClassName("ContextThemeWrapper", "C2106b1").isEqualTo("ContextThemeWrapper");
+		assertThatBetterClassName("ListPopupWindow", "C2344a3").isEqualTo("ListPopupWindow");
+	}
+
+	@Test
+	public void testShortGoodNamesVsGeneratedAliases() {
+		assertThatBetterClassName("Room", "C2937kh").isEqualTo("Room");
+		assertThatBetterClassName("Fade", "C1428qi").isEqualTo("Fade");
+		assertThatBetterClassName("Scene", "C4063yi").isEqualTo("Scene");
+	}
+
+	@Test
+	public void testGoodNamesVsGeneratedAliasesWithPrefix() {
+		assertThatBetterClassName("AppCompatActivity", "ActivityC2646h0").isEqualTo("AppCompatActivity");
+		assertThatBetterClassName("PagerAdapter", "AbstractC3038lk").isEqualTo("PagerAdapter");
+		assertThatBetterClassName("Lazy", "InterfaceC6434a").isEqualTo("Lazy");
+		assertThatBetterClassName("MembersInjector", "InterfaceC6435b").isEqualTo("MembersInjector");
+		assertThatBetterClassName("Subscriber", "InterfaceC6439c").isEqualTo("Subscriber");
+	}
+
+	@Test
+	public void testGoodNamesWithDigitsVsGeneratedAliases() {
+		assertThatBetterClassName("ISO8061Formatter", "C1121uq4").isEqualTo("ISO8061Formatter");
+		assertThatBetterClassName("Jdk9Platform", "C1189rn6").isEqualTo("Jdk9Platform");
+		assertThatBetterClassName("WrappedDrawableApi14", "C2847i9").isEqualTo("WrappedDrawableApi14");
+		assertThatBetterClassName("WrappedDrawableApi21", "C2888j9").isEqualTo("WrappedDrawableApi21");
+	}
+
+	@Test
+	public void testShortNamesVsLongNames() {
+		assertThatBetterClassName("az", "Observer").isEqualTo("Observer");
+		assertThatBetterClassName("bb", "RenderEvent").isEqualTo("RenderEvent");
+		assertThatBetterClassName("aaaa", "FontUtils").isEqualTo("FontUtils");
+	}
+
+	/**
+	 * Tests {@link BetterName#getBetterClassName(String, String)} on equally good names.
+	 * In this case, according to the documentation, the method should return the first argument.
+	 *
+	 * @see BetterName#getBetterClassName(String, String)
+	 */
+	@Test
+	public void testEquallyGoodNames() {
+		assertThatBetterClassName("AAAA", "BBBB").isEqualTo("AAAA");
+		assertThatBetterClassName("BBBB", "AAAA").isEqualTo("BBBB");
+
+		assertThatBetterClassName("XYXYXY", "YZYZYZ").isEqualTo("XYXYXY");
+		assertThatBetterClassName("YZYZYZ", "XYXYXY").isEqualTo("YZYZYZ");
+	}
+
+	private AbstractStringAssert<?> assertThatBetterClassName(String firstName, String secondName) {
+		return assertThat(getBetterClassName(firstName, secondName));
+	}
+}

jadx-core/src/test/java/jadx/core/utils/TestGetBetterResourceName.java

@@ -0,0 +1,37 @@
+package jadx.core.utils;
+
+import org.assertj.core.api.AbstractStringAssert;
+import org.junit.jupiter.api.Test;
+
+import static jadx.core.utils.BetterName.getBetterResourceName;
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class TestGetBetterResourceName {
+
+	@Test
+	public void testGoodNamesVsSyntheticNames() {
+		assertThatBetterResourceName("color_main", "t0").isEqualTo("color_main");
+		assertThatBetterResourceName("done", "oOo0oO0o").isEqualTo("done");
+	}
+
+	/**
+	 * Tests {@link BetterName#getBetterResourceName(String, String)} on equally good names.
+	 * In this case, according to the documentation, the method should return the first argument.
+	 *
+	 * @see BetterName#getBetterResourceName(String, String)
+	 */
+	@Test
+	public void testEquallyGoodNames() {
+		assertThatBetterResourceName("AAAA", "BBBB").isEqualTo("AAAA");
+		assertThatBetterResourceName("BBBB", "AAAA").isEqualTo("BBBB");
+
+		assertThatBetterResourceName("Theme.AppCompat.Light", "Theme_AppCompat_Light")
+				.isEqualTo("Theme.AppCompat.Light");
+		assertThatBetterResourceName("Theme_AppCompat_Light", "Theme.AppCompat.Light")
+				.isEqualTo("Theme_AppCompat_Light");
+	}
+
+	private AbstractStringAssert<?> assertThatBetterResourceName(String firstName, String secondName) {
+		return assertThat(getBetterResourceName(firstName, secondName));
+	}
+}

jadx-core/src/test/java/jadx/tests/integration/rename/TestUsingSourceFileName.java

@@ -17,6 +17,14 @@ public void testNeverUseSourceName() {
 				.containsOne("class b {");
 	}
 
+	@Test
+	public void testIfBetterUseSourceName() {
+		args.setUseSourceNameAsClassNameAlias(UseSourceNameAsClassNameAlias.IF_BETTER);
+		assertThat(searchCls(loadFromSmaliFiles(), "b"))
+				.code()
+				.containsOne("class a {");
+	}
+
 	@Test
 	public void testAlwaysUseSourceName() {
 		args.setUseSourceNameAsClassNameAlias(UseSourceNameAsClassNameAlias.ALWAYS);
@@ -36,6 +44,17 @@ public void testNeverUseSourceNameWithDeobf() {
 				.containsOne("/* compiled from: a.java */");
 	}
 
+	@Test
+	public void testIfBetterUseSourceNameWithDeobf() {
+		args.setUseSourceNameAsClassNameAlias(UseSourceNameAsClassNameAlias.IF_BETTER);
+		enableDeobfuscation();
+		args.setDeobfuscationMinLength(100); // rename everything
+		assertThat(searchCls(loadFromSmaliFiles(), "b"))
+				.code()
+				.containsOne("class a {")
+				.containsOne("/* compiled from: a.java */");
+	}
+
 	@Test
 	public void testAlwaysUseSourceNameWithDeobf() {
 		args.setUseSourceNameAsClassNameAlias(UseSourceNameAsClassNameAlias.ALWAYS);
@@ -65,6 +84,18 @@ public void testDeprecatedUseSourceName() {
 				.containsOne("class a {");
 	}
 
+	@Test
+	public void testDeprecatedDontUseSourceNameWithDeobf() {
+		// noinspection deprecation
+		args.setUseSourceNameAsClassAlias(false);
+		enableDeobfuscation();
+		args.setDeobfuscationMinLength(100); // rename everything
+		assertThat(searchCls(loadFromSmaliFiles(), "b"))
+				.code()
+				.containsOne("class C0000b {")
+				.containsOne("/* compiled from: a.java */");
+	}
+
 	@Test
 	public void testDeprecatedUseSourceNameWithDeobf() {
 		// noinspection deprecation
@@ -73,7 +104,7 @@ public void testDeprecatedUseSourceNameWithDeobf() {
 		args.setDeobfuscationMinLength(100); // rename everything
 		assertThat(searchCls(loadFromSmaliFiles(), "b"))
 				.code()
-				.containsOne("class C0000b {")
+				.containsOne("class a {")
 				.containsOne("/* compiled from: a.java */");
 	}
 }