1 files changed, 80 insertions, 0 deletions
diff --git a/src/mongo/db/exec/sbe/sbe_test.cpp b/src/mongo/db/exec/sbe/sbe_test.cpp
index 323368a5334..5a577f02462 100644
--- a/src/mongo/db/exec/sbe/sbe_test.cpp
+++ b/src/mongo/db/exec/sbe/sbe_test.cpp
@@ -31,6 +31,7 @@
 #include "mongo/db/exec/sbe/values/value.h"
 #include "mongo/db/exec/sbe/vm/vm.h"
 #include "mongo/unittest/unittest.h"
+#include "mongo/util/pcre.h"
 
 namespace mongo::sbe {
 
@@ -421,6 +422,85 @@ TEST(SBEVM, ConvertBinDataToBsonObj) {
 
 namespace {
 
+// The hex representation of memory addresses in the output of CodeFragment::toString() differs on
+// Linux and Windows machines so 'addrPattern' is used to cover both cases.
+static const std::string kLinuxAddrPattern{"(0x[a-f0-9]+)"};
+static const std::string kWindowsAddrPattern{"([A-F0-9]+)"};
+static const std::string kAddrPattern{"(" + kLinuxAddrPattern + "|" + kWindowsAddrPattern + ")"};
+
+// The beginning of the output from CodeFragment::toString() gives a range of the addresses that
+// 'pcPointer' will traverse.
+static const std::string kPcPointerRangePattern{"(\\[" + kAddrPattern + ")-(" + kAddrPattern +
+                                                ")\\])"};
+
+/**
+ * Creates a pcre pattern to match the instructions in the output of CodeFragment::toString(). Any
+ * arguments must be passed in a single comma separated string, and no arguments can be represented
+ * using an empty string.
+ */
+std::string instrPattern(std::string op, std::string args) {
+    return "(" + kAddrPattern + ": " + op + "\\(" + args + "\\); )";
+}
+}  // namespace
+
+TEST(SBEVM, CodeFragmentToString) {
+    {
+        vm::CodeFragment code;
+        std::string toStringPattern{kPcPointerRangePattern + "( )"};
+
+        code.appendDiv();
+        toStringPattern += instrPattern("div", "");
+        code.appendMul();
+        toStringPattern += instrPattern("mul", "");
+        code.appendAdd();
+        toStringPattern += instrPattern("add", "");
+
+        std::string instrs = code.toString();
+
+        static const pcre::Regex validToStringOutput{toStringPattern};
+
+        ASSERT_TRUE(!!validToStringOutput.matchView(instrs));
+    }
+}
+
+TEST(SBEVM, CodeFragmentToStringArgs) {
+    {
+        vm::CodeFragment code;
+        std::string toStringPattern{kAddrPattern};
+
+        code.appendFillEmpty(vm::Instruction::True);
+        toStringPattern += instrPattern("fillEmptyConst", "k: True");
+        code.appendFillEmpty(vm::Instruction::Null);
+        toStringPattern += instrPattern("fillEmptyConst", "k: Null");
+        code.appendFillEmpty(vm::Instruction::False);
+        toStringPattern += instrPattern("fillEmptyConst", "k: False");
+
+        code.appendTraverseP(0xAA);
+        auto offsetP = 0xAA - code.instrs().size();
+        toStringPattern += instrPattern("traversePConst", "offset: " + std::to_string(offsetP));
+        code.appendTraverseF(0xBB, vm::Instruction::True);
+        auto offsetF = 0xBB - code.instrs().size();
+        toStringPattern +=
+            instrPattern("traverseFConst", "k: True, offset: " + std::to_string(offsetF));
+
+        auto [tag, val] = value::makeNewString("Hello world!");
+        value::ValueGuard guard{tag, val};
+        code.appendGetField(tag, val);
+        toStringPattern += instrPattern("getFieldConst", "value: \"Hello world!\"");
+
+        code.appendAdd();
+        toStringPattern += instrPattern("add", "");
+
+        std::string instrs = code.toString();
+
+        static const pcre::Regex validToStringOutput{toStringPattern};
+
+        ASSERT_TRUE(!!validToStringOutput.matchView(instrs));
+    }
+}
+
+namespace {
+
 /**
  * Fills bytes after the null terminator in the string with 'pattern'.
  *