1 files changed, 47 insertions, 0 deletions
diff --git a/src/mongo/db/pipeline/expression.cpp b/src/mongo/db/pipeline/expression.cpp
index 33d3c03c94e..016749ca29b 100644
--- a/src/mongo/db/pipeline/expression.cpp
+++ b/src/mongo/db/pipeline/expression.cpp
@@ -4781,6 +4781,17 @@ public:
         };
 
         //
+        // Conversions from String
+        //
+        table[BSONType::String][BSONType::NumberDouble] = &parseStringToNumber<double, 0>;
+        table[BSONType::String][BSONType::String] = &performIdentityConversion;
+        table[BSONType::String][BSONType::jstOID] = &parseStringToOID;
+        table[BSONType::String][BSONType::Bool] = [](Value inputValue) { return Value(true); };
+        table[BSONType::String][BSONType::NumberInt] = &parseStringToNumber<int, 10>;
+        table[BSONType::String][BSONType::NumberLong] = &parseStringToNumber<long long, 10>;
+        table[BSONType::String][BSONType::NumberDecimal] = &parseStringToNumber<Decimal128, 0>;
+
+        //
         // Conversions from jstOID
         //
         table[BSONType::jstOID][BSONType::Date] = [](Value inputValue) {
@@ -5017,6 +5028,42 @@ private:
         return Value(Date_t::fromMillisSinceEpoch(millisSinceEpoch));
     }
 
+    template <class targetType, int base>
+    static Value parseStringToNumber(Value inputValue) {
+        auto stringValue = inputValue.getStringData();
+        targetType result;
+
+        // Reject any strings in hex format. This check is needed because the
+        // parseNumberFromStringWithBase call below allows an input hex string prefixed by '0x' when
+        // parsing to a double.
+        uassert(ErrorCodes::ConversionFailure,
+                str::stream() << "Illegal hexadecimal input in $convert with no onError value: "
+                              << stringValue,
+                !stringValue.startsWith("0x"));
+
+        Status parseStatus = parseNumberFromStringWithBase(stringValue, base, &result);
+        uassert(ErrorCodes::ConversionFailure,
+                str::stream() << "Failed to parse number '" << stringValue
+                              << "' in $convert with no onError value: "
+                              << parseStatus.reason(),
+                parseStatus.isOK());
+
+        return Value(result);
+    }
+
+    static Value parseStringToOID(Value inputValue) {
+        try {
+            return Value(OID::createFromString(inputValue.getStringData()));
+        } catch (const DBException& ex) {
+            // Rethrow any caught exception as a conversion failure such that 'onError' is evaluated
+            // and returned.
+            uasserted(ErrorCodes::ConversionFailure,
+                      str::stream() << "Failed to parse objectId '" << inputValue.getString()
+                                    << "' in $convert with no onError value: "
+                                    << ex.reason());
+        }
+    }
+
     static Value performIdentityConversion(Value inputValue) {
         return inputValue;
     }