test/nbt_size_helpers: Implement tests for valid input

I stumbled over this when writing the unit test. Previously, it would return
an error code but explicitly mark it as not being an error. This was intended
behavior but I decided to change it because I didn’t anticipate it when writing
the test.

Technically `ErrorOr<T>` can be used to pass any message alongside `T`,
but practically, it is reasonable to assume that the error code is
`ErrorCodes::SUCCESS` when `isError` is false. Therefore, this feature
should be really only used in the weirdest edge cases - if at all.
Even then, it is most likely still preferable to flag it as an error and
just hand the resulting `T` back using the long constructor
`ErrorOr<T>(bool, uint8_t, T)`.

src/lib/nbt.cpp

@@ -395,8 +395,8 @@ namespace NBT {
             } else {
                 nextTag = data[currentPosition];
             }
-            // deal with compound tags separately
+            // deal with compound tags and lists separately
-            if (nextTag == TagType::COMPOUND || nextTag == TagType::LIST) return ErrorOr<uint64_t>(false, ErrorCodes::NOT_YET_KNOWN);
+            if (nextTag == TagType::COMPOUND || nextTag == TagType::LIST) return ErrorOr<uint64_t>(true, ErrorCodes::NOT_YET_KNOWN);
             // deal with end tag before trying to access the name
             if (nextTag == TagType::END) return ErrorOr<uint64_t>(1);
 

src/test/assert.hpp

@@ -15,4 +15,4 @@
 
 #include <iostream>
 
-#define ASSERT(truth) if ((truth)); else { std::cout << "Assertion failed: " << #truth << std::endl; return 1; }
+#define ASSERT(truth) if ((truth)); else { std::cout << "On line " << __LINE__ << ": Assertion failed: " << #truth << std::endl; return 1; }

src/test/nbt_size_helpers.cpp

@@ -28,17 +28,89 @@ int main() {
         << "################################################################################"
         << std::endl;
 
-    // end tag #########################################################
+    // a full copy of /resources/NBT_data/simple_nbt
-    // const uint8_t END        =  0;
+    //
-    uint8_t endTestData[] = {
+    // This contains all tag types. It is most likely not suitable for
-      0x00, 0x0a, 0x00, 0x11, 0x63, 0x6f, 0x6d, 0x70,
+    // tests chasing edge cases as it is - as the name says - really
-      0x6f, 0x75, 0x6e, 0x64, 0x5f, 0x6c, 0x65, 0x76,
+    // basic NBT data.
-      0x65, 0x6c, 0x5f, 0x32, 0x62, 0x05, 0x00, 0x03,
+    uint8_t simpleNBTData[] = {
-      0x33, 0x30, 0x30, 0x6e, 0x75, 0x6f, 0x70, 0x09,
+        0x0a, 0x00, 0x00, 0x08, 0x00, 0x3e, 0x53, 0x70,
-      0x00, 0x03
+        0x61, 0x63, 0x65, 0x73, 0x20, 0x61, 0x6e, 0x64,
+        0x20, 0x73, 0x70, 0x65, 0x63, 0x69, 0x61, 0x6c,
+        0x20, 0x63, 0x68, 0x61, 0x72, 0x61, 0x63, 0x74,
+        0x65, 0x72, 0x73, 0x20, 0x61, 0x72, 0x65, 0x20,
+        0x61, 0x6c, 0x6c, 0x6f, 0x77, 0x65, 0x64, 0x20,
+        0x69, 0x6e, 0x20, 0x74, 0x61, 0x67, 0x20, 0x6e,
+        0x61, 0x6d, 0x65, 0x73, 0x2c, 0x20, 0x72, 0x69,
+        0x67, 0x68, 0x74, 0x3f, 0x00, 0x16, 0x49, 0x64,
+        0x6b, 0x2e, 0x20, 0x4c, 0x65, 0x74, 0xe2, 0x80,
+        0x99, 0x73, 0x20, 0x66, 0x69, 0x6e, 0x64, 0x20,
+        0x6f, 0x75, 0x74, 0x2e, 0x0a, 0x00, 0x08, 0x63,
+        0x6f, 0x6d, 0x70, 0x6f, 0x75, 0x6e, 0x64, 0x03,
+        0x00, 0x0b, 0x73, 0x6f, 0x6d, 0x65, 0x5f, 0x6e,
+        0x75, 0x6d, 0x62, 0x65, 0x72, 0xd3, 0x07, 0x23,
+        0x41, 0x08, 0x00, 0x09, 0x73, 0x6f, 0x6d, 0x65,
+        0x5f, 0x74, 0x65, 0x78, 0x74, 0x00, 0x0c, 0x65,
+        0x61, 0x74, 0x20, 0x61, 0x20, 0x63, 0x6f, 0x6f,
+        0x6b, 0x69, 0x65, 0x00, 0x06, 0x00, 0x06, 0x64,
+        0x6f, 0x75, 0x62, 0x6c, 0x65, 0x41, 0x23, 0x07,
+        0xd3, 0x4e, 0xfd, 0x07, 0xf1, 0x05, 0x00, 0x05,
+        0x66, 0x6c, 0x6f, 0x61, 0x74, 0x42, 0x0d, 0x12,
+        0x43, 0x02, 0x00, 0x05, 0x69, 0x6e, 0x74, 0x31,
+        0x36, 0x07, 0xd0, 0x03, 0x00, 0x05, 0x69, 0x6e,
+        0x74, 0x33, 0x32, 0x00, 0x9a, 0x21, 0x12, 0x0b,
+        0x00, 0x0b, 0x69, 0x6e, 0x74, 0x33, 0x32, 0x5f,
+        0x61, 0x72, 0x72, 0x61, 0x79, 0x00, 0x00, 0x00,
+        0x04, 0x17, 0xbf, 0xe8, 0x3c, 0x00, 0x00, 0xa8,
+        0xfb, 0x7f, 0xff, 0xff, 0xff, 0x61, 0x72, 0x72,
+        0x61, 0x04, 0x00, 0x05, 0x69, 0x6e, 0x74, 0x36,
+        0x34, 0x00, 0x00, 0x00, 0xbc, 0x97, 0xde, 0x9e,
+        0x3e, 0x0c, 0x00, 0x0b, 0x69, 0x6e, 0x74, 0x36,
+        0x34, 0x5f, 0x61, 0x72, 0x72, 0x61, 0x79, 0x00,
+        0x00, 0x00, 0x05, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x03, 0xa8, 0xf9, 0x00, 0x00, 0x00, 0x00, 0x01,
+        0x67, 0xe7, 0xbd, 0x7f, 0xff, 0xff, 0xff, 0xff,
+        0xff, 0xff, 0xff, 0x00, 0x00, 0xab, 0xd8, 0x00,
+        0x00, 0xab, 0xd8, 0x00, 0x0b, 0x12, 0x21, 0x00,
+        0x79, 0x61, 0x72, 0x01, 0x00, 0x04, 0x69, 0x6e,
+        0x74, 0x38, 0x64, 0x07, 0x00, 0x0a, 0x69, 0x6e,
+        0x74, 0x38, 0x5f, 0x61, 0x72, 0x72, 0x61, 0x79,
+        0x00, 0x00, 0x00, 0x08, 0x71, 0x35, 0x77, 0x62,
+        0x54, 0x64, 0xf5, 0x32, 0x09, 0x00, 0x09, 0x6c,
+        0x69, 0x73, 0x74, 0x5f, 0x69, 0x6e, 0x74, 0x38,
+        0x01, 0x00, 0x00, 0x00, 0x05, 0x41, 0x60, 0x4e,
+        0x7f, 0xfa, 0x09, 0x00, 0x0c, 0x6c, 0x69, 0x73,
+        0x74, 0x5f, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67,
+        0x73, 0x08, 0x00, 0x00, 0x00, 0x0c, 0x00, 0x06,
+        0x50, 0x61, 0x63, 0x6d, 0x61, 0x6e, 0x00, 0x03,
+        0x61, 0x74, 0x65, 0x00, 0x03, 0x61, 0x6c, 0x6c,
+        0x00, 0x03, 0x74, 0x68, 0x65, 0x00, 0x04, 0x64,
+        0x6f, 0x74, 0x73, 0x00, 0x02, 0x73, 0x6f, 0x00,
+        0x03, 0x6e, 0x6f, 0x77, 0x00, 0x06, 0x68, 0x65,
+        0xe2, 0x80, 0x99, 0x73, 0x00, 0x06, 0x63, 0x6f,
+        0x6d, 0x69, 0x6e, 0x67, 0x00, 0x03, 0x66, 0x6f,
+        0x72, 0x00, 0x03, 0x74, 0x68, 0x65, 0x00, 0x06,
+        0x77, 0x6f, 0x72, 0x64, 0x73, 0x2e, 0x08, 0x00,
+        0x06, 0x73, 0x74, 0x72, 0x69, 0x6e, 0x67, 0x00,
+        0x0c, 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x57,
+        0x6f, 0x72, 0x6c, 0x64, 0x21, 0x00
     };
-    ErrorOr<uint64_t> totalSize = NBT::helper::totalTagSize(endTestData, 34, 0);
+    uint64_t simpleNBTDataSize = 478;
-    ErrorOr<int32_t> dataLength = NBT::helper::containedDataLength(endTestData, 34, 0);
+
+    //##################################################################
+    // Basic valid data tests
+    //##################################################################
+    // const uint8_t END        =  0;
+    ErrorOr<uint64_t> totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x93);
+    ErrorOr<int32_t> dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x93);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 1);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 0);
+
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 477);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 477);
 
     ASSERT(!totalSize.isError);
     ASSERT(totalSize.value == 1);
@@ -46,17 +118,140 @@ int main() {
     ASSERT(dataLength.value == 0);
 
     //const uint8_t INT8       =  1;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x133);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x133);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 8);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 1);
+
     //const uint8_t INT16      =  2;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0xb1);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0xb1);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 10);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 1);
+
     //const uint8_t INT32      =  3;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0xbb);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0xbb);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 12);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 1);
+
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x67);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x67);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 18);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 1);
+
     //const uint8_t INT64      =  4;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0xe9);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0xe9);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 16);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 1);
+
     //const uint8_t FLOAT      =  5;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0xa5);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0xa5);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 12);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 1);
+
     //const uint8_t DOUBLE     =  6;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x94);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x94);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 17);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 1);
+
     //const uint8_t INT8_ARRAY =  7;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x13b);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x13b);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 25);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 8);
+
     //const uint8_t STRING     =  8;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x1c6);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x1c6);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 23);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 12);
+
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x79);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x79);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 26);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 12);
+
     //const uint8_t LIST       =  9;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x154);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x154);
+
+    ASSERT(totalSize.isError);
+    ASSERT(totalSize.errorCode == ErrorCodes::NOT_YET_KNOWN);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 5);
+
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x16a);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x16a);
+
+    ASSERT(totalSize.isError);
+    ASSERT(totalSize.errorCode == ErrorCodes::NOT_YET_KNOWN);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 12);
+
     //const uint8_t COMPOUND   = 10;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0x5c);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0x5c);
+
+    ASSERT(totalSize.isError);
+    ASSERT(totalSize.errorCode == ErrorCodes::NOT_YET_KNOWN);
+    ASSERT(dataLength.isError);
+    ASSERT(dataLength.errorCode == ErrorCodes::NOT_YET_KNOWN);
+
     //const uint8_t INT32_ARRAY= 11;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0xc7);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0xc7);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 34);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 4);
+
     //const uint8_t INT64_ARRAY= 12;
+    totalSize = NBT::helper::totalTagSize(simpleNBTData, simpleNBTDataSize, 0xf9);
+    dataLength = NBT::helper::containedDataLength(simpleNBTData, simpleNBTDataSize, 0xf9);
+
+    ASSERT(!totalSize.isError);
+    ASSERT(totalSize.value == 58);
+    ASSERT(!dataLength.isError);
+    ASSERT(dataLength.value == 5);
+
+    std::cout << "Passed simple valid data test." << std::endl;
+
+    //TODO: add tests for errors and edge cases
 
     return 0;
 }