Preserve binary literals in Wave output

Author: AnastaZIuk

src/nbl/asset/utils/CWaveStringResolver.cpp

@@ -134,6 +134,48 @@ std::string tokenValueToString(const TokenT& token)
     return std::string(value.data(), value.size());
 }
 
+bool isBinaryLiteralTail(const std::string_view value)
+{
+    if (value.size() < 2u)
+        return false;
+
+    if (value.front() != 'b' && value.front() != 'B')
+        return false;
+
+    bool hasBinaryDigit = false;
+    size_t i = 1u;
+    for (; i < value.size(); ++i)
+    {
+        const char c = value[i];
+        if (c == '0' || c == '1')
+        {
+            hasBinaryDigit = true;
+            continue;
+        }
+        if (c == '\'')
+            continue;
+        break;
+    }
+
+    if (!hasBinaryDigit)
+        return false;
+
+    for (; i < value.size(); ++i)
+    {
+        const char c = value[i];
+        const bool isIntegerSuffix = c == 'u' || c == 'U' || c == 'l' || c == 'L' || c == 'z' || c == 'Z';
+        if (!isIntegerSuffix)
+            return false;
+    }
+
+    return true;
+}
+
+bool shouldConcatenateWithoutWhitespace(const std::string_view previousValue, const std::string_view currentValue)
+{
+    return previousValue == "0" && isBinaryLiteralTail(currentValue);
+}
+
 core::string renderPreprocessedOutput(nbl::wave::context& context)
 {
     using namespace boost::wave;
@@ -142,6 +184,7 @@ core::string renderPreprocessedOutput(nbl::wave::context& context)
     util::insert_whitespace_detection whitespace(true);
     std::optional<nbl::wave::context::position_type> previousPosition = std::nullopt;
     bool previousWasExplicitWhitespace = false;
+    std::string previousTokenValue;
 
     for (auto it = context.begin(); it != context.end(); ++it)
     {
@@ -168,7 +211,7 @@ core::string renderPreprocessedOutput(nbl::wave::context& context)
                     whitespace.shift_tokens(T_NEWLINE);
                 }
             }
-            else if (!previousWasExplicitWhitespace && whitespace.must_insert(id, value))
+            else if (!previousWasExplicitWhitespace && !shouldConcatenateWithoutWhitespace(previousTokenValue, value) && whitespace.must_insert(id, value))
             {
                 if (output.empty() || (output.back() != ' ' && output.back() != '\n' && output.back() != '\r' && output.back() != '\t'))
                 {
@@ -182,6 +225,8 @@ core::string renderPreprocessedOutput(nbl::wave::context& context)
         whitespace.shift_tokens(id);
         previousPosition = position;
         previousWasExplicitWhitespace = explicitWhitespace;
+        if (!explicitWhitespace)
+            previousTokenValue = value;
     }
 
     return output;