putting b64 decoding test resources under a b64 directory

Author: nklapste

src/test/java/jadx/plugins/stringdecoder/JadxStringDecoderPluginTest.java

@@ -15,14 +15,74 @@ class JadxStringDecoderPluginTest {
 
 	@Test
 	public void integrationTest() throws Exception {
+		String code = decompileSmali("b64/hello.smali");
+		System.out.println(code);
+		assertThat(code).contains("b64: Hello, World!");
+	}
+
+	@Test
+	public void notB64Test() throws Exception {
+		// "Hello, World!" contains non-Base64 chars — no comment expected
+		String code = decompileSmali("b64/not_b64.smali");
+		System.out.println(code);
+		assertThat(code).doesNotContain("b64:");
+	}
+
+	@Test
+	public void looksLikeB64Test() throws Exception {
+		// "AQIDBAUG" matches the Base64 charset but decodes to binary [1,2,3,4,5,6] — not printable UTF-8, no comment expected
+		String code = decompileSmali("b64/looks_like_b64.smali");
+		System.out.println(code);
+		assertThat(code).doesNotContain("b64:");
+	}
+
+	@Test
+	public void b64DecodableNotEncodedTest() throws Exception {
+		// "aGVsbG8=" is not intentionally Base64-encoded but decodes to "hello" — plugin adds a comment (known false positive)
+		String code = decompileSmali("b64/b64_decodable.smali");
+		System.out.println(code);
+		assertThat(code).contains("b64: hello");
+	}
+
+	@Test
+	public void fieldB64Test() throws Exception {
+		// Base64 string assigned to a static field in <clinit>
+		String code = decompileSmali("b64/field_b64.smali");
+		System.out.println(code);
+		assertThat(code).contains("b64: Hello, World!");
+	}
+
+	@Test
+	public void varAssignB64Test() throws Exception {
+		// Base64 string used twice — may be kept as an explicit local variable in decompiled output
+		String code = decompileSmali("b64/var_assign_b64.smali");
+		System.out.println(code);
+		assertThat(code).contains("b64: Hello, World!");
+	}
+
+	@Test
+	public void longDecodedStringTest() throws Exception {
+		// Decoded string is 650 'A' chars — truncated to 100 chars + "..." in the comment
+		String code = decompileSmali("b64/long_b64.smali");
+		System.out.println(code);
+		assertThat(code).contains("b64: " + "A".repeat(100) + "...");
+	}
+
+	@Test
+	public void multilineDecodedStringTest() throws Exception {
+		// Decoded string contains newlines — they should be escaped as \n in the comment
+		String code = decompileSmali("b64/multiline_b64.smali");
+		System.out.println(code);
+		assertThat(code).contains("b64: Line 1\\nLine 2\\nLine 3");
+	}
+
+	private String decompileSmali(String fileName) throws Exception {
 		JadxArgs args = new JadxArgs();
-		args.getInputFiles().add(getSampleFile("hello.smali"));
+		args.getInputFiles().add(getSampleFile(fileName));
 		try (JadxDecompiler jadx = new JadxDecompiler(args)) {
 			jadx.load();
 			JavaClass cls = jadx.getClasses().get(0);
-			String clsCode = cls.getCode();
-			System.out.println(clsCode);
-			assertThat(clsCode).contains("b64: Hello, World!");
+			return cls.getCode();
 		}
 	}
 

src/test/resources/samples/b64/b64_decodable.smali

@@ -0,0 +1,9 @@
+.class LB64Decodable;
+.super Ljava/lang/Object;
+
+# "aGVsbG8=" is not intentionally Base64-encoded but decodes to "hello"
+.method public static test()Ljava/lang/String;
+    .registers 1
+    const-string v0, "aGVsbG8="
+    return-object v0
+.end method

src/test/resources/samples/b64/field_b64.smali

@@ -0,0 +1,12 @@
+.class LFieldB64;
+.super Ljava/lang/Object;
+
+.field public secret:Ljava/lang/String;
+
+# Assigned in a regular method so the instruction stays in the method body (not extracted as a field initializer)
+.method public setSecret()V
+    .registers 2
+    const-string v0, "SGVsbG8sIFdvcmxkIQ=="
+    iput-object v0, p0, LFieldB64;->secret:Ljava/lang/String;
+    return-void
+.end method

src/test/resources/samples/hello.smali …c/test/resources/samples/b64/hello.smalisrc/test/resources/samples/hello.smali renamed to src/test/resources/samples/b64/hello.smali src/test/resources/samples/hello.smali renamed to src/test/resources/samples/b64/hello.smali

@@ -0,0 +1,9 @@
+.class LLongB64;
+.super Ljava/lang/Object;
+
+# "A" * 650 base64-encoded — decoded output is 650 chars and should be truncated to 100 + "..." in the comment
+.method public static test()Ljava/lang/String;
+    .registers 1
+    const-string v0, "QUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUE="
+    return-object v0
+.end method

src/test/resources/samples/b64/long_b64.smali

@@ -0,0 +1,9 @@
+.class LLooksLikeB64;
+.super Ljava/lang/Object;
+
+# "AQIDBAUG" matches the Base64 charset but decodes to binary [1,2,3,4,5,6] — not printable UTF-8
+.method public static test()Ljava/lang/String;
+    .registers 1
+    const-string v0, "AQIDBAUG"
+    return-object v0
+.end method

src/test/resources/samples/b64/looks_like_b64.smali

@@ -0,0 +1,9 @@
+.class LMultilineB64;
+.super Ljava/lang/Object;
+
+# "TGluZSAxCkxpbmUgMgpMaW5lIDM=" decodes to "Line 1\nLine 2\nLine 3"
+.method public static test()Ljava/lang/String;
+    .registers 1
+    const-string v0, "TGluZSAxCkxpbmUgMgpMaW5lIDM="
+    return-object v0
+.end method

src/test/resources/samples/b64/multiline_b64.smali

@@ -0,0 +1,8 @@
+.class LNotB64;
+.super Ljava/lang/Object;
+
+.method public static test()Ljava/lang/String;
+    .registers 1
+    const-string v0, "Hello, World!"
+    return-object v0
+.end method

src/test/resources/samples/b64/not_b64.smali

@@ -0,0 +1,12 @@
+.class LVarAssignB64;
+.super Ljava/lang/Object;
+
+# v0 is used twice so it may be kept as an explicit variable in the decompiled output
+.method public static main([Ljava/lang/String;)V
+    .registers 2
+    const-string v0, "SGVsbG8sIFdvcmxkIQ=="
+    sget-object p0, Ljava/lang/System;->out:Ljava/io/PrintStream;
+    invoke-virtual {p0, v0}, Ljava/io/PrintStream;->println(Ljava/lang/String;)V
+    invoke-virtual {p0, v0}, Ljava/io/PrintStream;->println(Ljava/lang/String;)V
+    return-void
+.end method