SERVER-61566 Fix and extract coercion to 32-bit int logic in expression parsing

2 files changed, 29 insertions, 2 deletions

diff --git a/src/mongo/bson/bsonelement.cpp b/src/mongo/bson/bsonelement.cpp
index d93f928861c..e02dfd07f33 100644
--- a/src/mongo/bson/bsonelement.cpp
+++ b/src/mongo/bson/bsonelement.cpp
@@ -515,7 +515,8 @@ StatusWith<long long> BSONElement::parseIntegerElementToNonNegativeLong() const
 
     if (number.getValue() < 0) {
         return Status(ErrorCodes::FailedToParse,
-                      str::stream() << "Expected a positive number in: " << toString(true, true));
+                      str::stream()
+                          << "Expected a non-negative number in: " << toString(true, true));
     }
 
     return number;
@@ -585,6 +586,21 @@ StatusWith<int> BSONElement::parseIntegerElementToInt() const {
     return static_cast<int>(valueLong);
 }
 
+StatusWith<int> BSONElement::parseIntegerElementToNonNegativeInt() const {
+    auto number = parseIntegerElementToInt();
+    if (!number.isOK()) {
+        return number;
+    }
+
+    if (number.getValue() < 0) {
+        return Status(ErrorCodes::FailedToParse,
+                      str::stream()
+                          << "Expected a non-negative number in: " << toString(true, true));
+    }
+
+    return number;
+}
+
 BSONObj BSONElement::embeddedObjectUserCheck() const {
     if (MONGO_likely(isABSONObj()))
         return BSONObj(value(), BSONObj::LargeSizeTrait{});
diff --git a/src/mongo/bson/bsonelement.h b/src/mongo/bson/bsonelement.h
index 11a8ad6994a..c99623c7e80 100644
--- a/src/mongo/bson/bsonelement.h
+++ b/src/mongo/bson/bsonelement.h
@@ -412,7 +412,7 @@ public:
     long long exactNumberLong() const;
 
     /**
-     * Parses a BSONElement of any numeric type into a positive long long, failing if the value
+     * Parses a BSONElement of any numeric type into a non-negative long long, failing if the value
      * is any of the following:
      *
      * - NaN.
@@ -433,6 +433,17 @@ public:
     StatusWith<long long> parseIntegerElementToLong() const;
 
     /**
+     * Parses a BSONElement of any numeric type into a non-negative int, failing if the value
+     * is any of the following:
+     *
+     * - NaN
+     * - Negative
+     * - a non-integral number
+     * - too large in the positive or negative direction to fit in an int
+     */
+    StatusWith<int> parseIntegerElementToNonNegativeInt() const;
+
+    /**
      * Parses a BSONElement of any numeric type into an integer, failing if the value is:
      *
      * - NaN