SERVER-66923 Removed kFullyDowngradedTo_5_0 constants in the codebase

10 files changed, 50 insertions, 108 deletions

diff --git a/src/mongo/db/commands/find_and_modify.cpp b/src/mongo/db/commands/find_and_modify.cpp
index 2751fa9b8dd..0c4001fafe7 100644
--- a/src/mongo/db/commands/find_and_modify.cpp
+++ b/src/mongo/db/commands/find_and_modify.cpp
@@ -495,10 +495,7 @@ write_ops::FindAndModifyCommandReply CmdFindAndModify::Invocation::writeConflict
     write_ops_exec::recordUpdateResultInOpDebug(updateResult, opDebug);
     opDebug->setPlanSummaryMetrics(summaryStats);
 
-    if (updateResult.containsDotsAndDollarsField &&
-        serverGlobalParams.featureCompatibility.isVersionInitialized() &&
-        serverGlobalParams.featureCompatibility.isGreaterThanOrEqualTo(
-            multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0)) {
+    if (updateResult.containsDotsAndDollarsField) {
         // If it's an upsert, increment 'inserts' metric, otherwise increment 'updates'.
         dotsAndDollarsFieldsCounters.incrementForUpsert(!updateResult.upsertedId.isEmpty());
     }
diff --git a/src/mongo/db/exec/upsert_stage.cpp b/src/mongo/db/exec/upsert_stage.cpp
index 9d60495646c..06235a9ac52 100644
--- a/src/mongo/db/exec/upsert_stage.cpp
+++ b/src/mongo/db/exec/upsert_stage.cpp
@@ -294,12 +294,9 @@ void UpsertStage::_assertDocumentToBeInsertedIsValid(const mb::Document& documen
         // should always have an _id here, since we generated one earlier if not already present.
         invariant(document.root().ok() && document.root()[idFieldName].ok());
         bool containsDotsAndDollarsField = false;
-        bool allowTopLevelDollarPrefixes =
-            serverGlobalParams.featureCompatibility.isVersionInitialized() &&
-            serverGlobalParams.featureCompatibility.isGreaterThanOrEqualTo(
-                multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
+
         storage_validation::scanDocument(document,
-                                         allowTopLevelDollarPrefixes,
+                                         true, /* allowTopLevelDollarPrefixes */
                                          true, /* Should validate for storage */
                                          &containsDotsAndDollarsField);
         if (containsDotsAndDollarsField)
diff --git a/src/mongo/db/matcher/expression_parser.cpp b/src/mongo/db/matcher/expression_parser.cpp
index caef2981ef1..f3faa022c89 100644
--- a/src/mongo/db/matcher/expression_parser.cpp
+++ b/src/mongo/db/matcher/expression_parser.cpp
@@ -299,9 +299,7 @@ StatusWithMatchExpression parse(const BSONObj& obj,
                 std::string hint = "";
                 if (name == "not") {
                     hint = ". If you are trying to negate an entire expression, use $nor.";
-                } else if (serverGlobalParams.featureCompatibility.isVersionInitialized() &&
-                           serverGlobalParams.featureCompatibility.isGreaterThanOrEqualTo(
-                               multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0)) {
+                } else {
                     hint =
                         ". If you have a field name that starts with a '$' symbol, consider using "
                         "$getField or $setField.";
diff --git a/src/mongo/db/ops/insert.cpp b/src/mongo/db/ops/insert.cpp
index 8db1935b4b8..b1c3626af3e 100644
--- a/src/mongo/db/ops/insert.cpp
+++ b/src/mongo/db/ops/insert.cpp
@@ -112,20 +112,12 @@ StatusWith<BSONObj> fixDocumentForInsert(OperationContext* opCtx,
 
             auto fieldName = e.fieldNameStringData();
 
-            if (fieldName[0] == '$') {
-                if (!serverGlobalParams.featureCompatibility.isVersionInitialized() ||
-                    !serverGlobalParams.featureCompatibility.isGreaterThanOrEqualTo(
-                        multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0)) {
-                    return StatusWith<BSONObj>(ErrorCodes::BadValue,
-                                               str::stream()
-                                                   << "Document can't have $ prefixed field names: "
-                                                   << fieldName);
-                } else if (containsDotsAndDollarsField) {
-                    *containsDotsAndDollarsField = true;
-                    // If the internal validation is disabled and we confirm this doc contains
-                    // dots/dollars field name, we can skip other validations below.
-                    if (validationDisabled)
-                        return StatusWith<BSONObj>(BSONObj());
+            if (fieldName[0] == '$' && containsDotsAndDollarsField) {
+                *containsDotsAndDollarsField = true;
+                // If the internal validation is disabled and we confirm this doc contains
+                // dots/dollars field name, we can skip other validations below.
+                if (validationDisabled) {
+                    return StatusWith<BSONObj>(BSONObj());
                 }
             }
 
diff --git a/src/mongo/db/pipeline/document_source_set_window_fields.cpp b/src/mongo/db/pipeline/document_source_set_window_fields.cpp
index 45223bb1cf4..0920fdda988 100644
--- a/src/mongo/db/pipeline/document_source_set_window_fields.cpp
+++ b/src/mongo/db/pipeline/document_source_set_window_fields.cpp
@@ -75,19 +75,15 @@ bool modifiedSortPaths(const SortPattern& pat, const DocumentSource::GetModPaths
 }
 }  // namespace
 
-REGISTER_DOCUMENT_SOURCE_WITH_MIN_VERSION(
-    setWindowFields,
-    LiteParsedDocumentSourceDefault::parse,
-    document_source_set_window_fields::createFromBson,
-    AllowedWithApiStrict::kAlways,
-    multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
-
-REGISTER_DOCUMENT_SOURCE_WITH_MIN_VERSION(
-    _internalSetWindowFields,
-    LiteParsedDocumentSourceDefault::parse,
-    DocumentSourceInternalSetWindowFields::createFromBson,
-    AllowedWithApiStrict::kAlways,
-    multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
+REGISTER_DOCUMENT_SOURCE(setWindowFields,
+                         LiteParsedDocumentSourceDefault::parse,
+                         document_source_set_window_fields::createFromBson,
+                         AllowedWithApiStrict::kAlways);
+
+REGISTER_DOCUMENT_SOURCE(_internalSetWindowFields,
+                         LiteParsedDocumentSourceDefault::parse,
+                         DocumentSourceInternalSetWindowFields::createFromBson,
+                         AllowedWithApiStrict::kAlways);
 
 list<intrusive_ptr<DocumentSource>> document_source_set_window_fields::createFromBson(
     BSONElement elem, const intrusive_ptr<ExpressionContext>& expCtx) {
diff --git a/src/mongo/db/pipeline/expression.cpp b/src/mongo/db/pipeline/expression.cpp
index 774a337f740..1524e7d0ee7 100644
--- a/src/mongo/db/pipeline/expression.cpp
+++ b/src/mongo/db/pipeline/expression.cpp
@@ -7759,12 +7759,8 @@ void ExpressionDateTrunc::_doAddDependencies(DepsTracker* deps) const {
 }
 
 /* -------------------------- ExpressionGetField ------------------------------ */
-REGISTER_EXPRESSION_WITH_MIN_VERSION(
-    getField,
-    ExpressionGetField::parse,
-    AllowedWithApiStrict::kAlways,
-    AllowedWithClientType::kAny,
-    multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
+
+REGISTER_STABLE_EXPRESSION(getField, ExpressionGetField::parse);
 
 intrusive_ptr<Expression> ExpressionGetField::parse(ExpressionContext* const expCtx,
                                                     BSONElement expr,
@@ -7871,20 +7867,11 @@ Value ExpressionGetField::serialize(const bool explain) const {
 }
 
 /* -------------------------- ExpressionSetField ------------------------------ */
-REGISTER_EXPRESSION_WITH_MIN_VERSION(
-    setField,
-    ExpressionSetField::parse,
-    AllowedWithApiStrict::kAlways,
-    AllowedWithClientType::kAny,
-    multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
+
+REGISTER_STABLE_EXPRESSION(setField, ExpressionSetField::parse);
 
 // $unsetField is syntactic sugar for $setField where value is set to $$REMOVE.
-REGISTER_EXPRESSION_WITH_MIN_VERSION(
-    unsetField,
-    ExpressionSetField::parse,
-    AllowedWithApiStrict::kNeverInVersion1,
-    AllowedWithClientType::kAny,
-    multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
+REGISTER_STABLE_EXPRESSION(unsetField, ExpressionSetField::parse);
 
 intrusive_ptr<Expression> ExpressionSetField::parse(ExpressionContext* const expCtx,
                                                     BSONElement expr,
@@ -8015,12 +8002,7 @@ Value ExpressionTsSecond::evaluate(const Document& root, Variables* variables) c
     return Value(static_cast<long long>(operand.getTimestamp().getSecs()));
 }
 
-REGISTER_EXPRESSION_WITH_MIN_VERSION(
-    tsSecond,
-    ExpressionTsSecond::parse,
-    AllowedWithApiStrict::kAlways,
-    AllowedWithClientType::kAny,
-    multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
+REGISTER_STABLE_EXPRESSION(tsSecond, ExpressionTsSecond::parse);
 
 /* ------------------------- ExpressionTsIncrement ----------------------------- */
 
@@ -8039,12 +8021,7 @@ Value ExpressionTsIncrement::evaluate(const Document& root, Variables* variables
     return Value(static_cast<long long>(operand.getTimestamp().getInc()));
 }
 
-REGISTER_EXPRESSION_WITH_MIN_VERSION(
-    tsIncrement,
-    ExpressionTsIncrement::parse,
-    AllowedWithApiStrict::kAlways,
-    AllowedWithClientType::kAny,
-    multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
+REGISTER_STABLE_EXPRESSION(tsIncrement, ExpressionTsIncrement::parse);
 
 MONGO_INITIALIZER_GROUP(BeginExpressionRegistration, ("default"), ("EndExpressionRegistration"))
 MONGO_INITIALIZER_GROUP(EndExpressionRegistration, ("BeginExpressionRegistration"), ())
diff --git a/src/mongo/db/pipeline/field_path.cpp b/src/mongo/db/pipeline/field_path.cpp
index ab00617bbd3..c860e863512 100644
--- a/src/mongo/db/pipeline/field_path.cpp
+++ b/src/mongo/db/pipeline/field_path.cpp
@@ -100,12 +100,7 @@ FieldPath::FieldPath(std::string inputPath)
 void FieldPath::uassertValidFieldName(StringData fieldName) {
     uassert(15998, "FieldPath field names may not be empty strings.", !fieldName.empty());
 
-    const auto dotsAndDollarsHint =
-        serverGlobalParams.featureCompatibility.isVersionInitialized() &&
-            serverGlobalParams.featureCompatibility.isGreaterThanOrEqualTo(
-                multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0)
-        ? " Consider using $getField or $setField."
-        : "";
+    const auto dotsAndDollarsHint = " Consider using $getField or $setField.";
 
     if (fieldName[0] == '$' && !kAllowedDollarPrefixedFields.count(fieldName)) {
         uasserted(16410,
diff --git a/src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp b/src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp
index 7cfbe29f304..b290f2b3a62 100644
--- a/src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp
+++ b/src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp
@@ -207,16 +207,20 @@ std::string WiredTigerFileVersion::getDowngradeString() {
     // With the introduction of continuous releases, there are two downgrade paths from kLatest.
     // Either to kLastContinuous or kLastLTS. It's possible for the data format to differ between
     // kLastContinuous and kLastLTS and we'll need to handle that appropriately here. We only
-    // consider downgrading when FCV has been fully downgraded. This will have to be updated for new
-    // releases.
+    // consider downgrading when FCV has been fully downgraded.
     const auto currentVersion = serverGlobalParams.featureCompatibility.getVersion();
-    if (currentVersion == multiversion::FeatureCompatibilityVersion::kVersion_5_1) {
-        // If the data format between kLatest (v5.2) and kLastContinuous (v5.1) differs, change the
+    // (Generic FCV reference): This FCV check should exist across LTS binary versions because the
+    // logic for keeping the WiredTiger release version compatible with the server FCV version will
+    // be the same across different LTS binary versions.
+    if (currentVersion == multiversion::GenericFCV::kLastContinuous) {
+        // If the data format between kLatest and kLastContinuous differs, change the
         // 'kLastContinuousWTRelease' version.
         return kLastContinuousWTRelease;
-    } else if (currentVersion ==
-               multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0) {
-        // If the data format between kLatest (v5.2) and kLastLTS (v5.0) differs, change the
+        // (Generic FCV reference): This FCV check should exist across LTS binary versions because
+        // the logic for keeping the WiredTiger release version compatible with the server FCV
+        // version will be the same across different LTS binary versions.
+    } else if (currentVersion == multiversion::GenericFCV::kLastLTS) {
+        // If the data format between kLatest and kLastLTS differs, change the
         // 'kLastLTSWTRelease' version.
         return kLastLTSWTRelease;
     }
diff --git a/src/mongo/db/update/pipeline_executor.cpp b/src/mongo/db/update/pipeline_executor.cpp
index 710803d6b04..acbe69b133f 100644
--- a/src/mongo/db/update/pipeline_executor.cpp
+++ b/src/mongo/db/update/pipeline_executor.cpp
@@ -103,12 +103,11 @@ UpdateExecutor::ApplyResult PipelineExecutor::applyUpdate(ApplyParams applyParam
 
     // Replace the pre-image document in applyParams with the post image we got from running the
     // post image.
-    bool allowTopLevelDollarPrefixedFields =
-        serverGlobalParams.featureCompatibility.isVersionInitialized() &&
-        serverGlobalParams.featureCompatibility.isGreaterThanOrEqualTo(
-            multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
-    auto ret = ObjectReplaceExecutor::applyReplacementUpdate(
-        applyParams, transformedDoc, transformedDocHasIdField, allowTopLevelDollarPrefixedFields);
+    auto ret =
+        ObjectReplaceExecutor::applyReplacementUpdate(applyParams,
+                                                      transformedDoc,
+                                                      transformedDocHasIdField,
+                                                      true /* allowTopLevelDollarPrefixedFields */);
 
     // The oplog entry should not have been populated yet.
     invariant(ret.oplogEntry.isEmpty());
diff --git a/src/mongo/db/update/storage_validation.cpp b/src/mongo/db/update/storage_validation.cpp
index d94c645a588..0feb5877ef5 100644
--- a/src/mongo/db/update/storage_validation.cpp
+++ b/src/mongo/db/update/storage_validation.cpp
@@ -112,17 +112,12 @@ void validateDollarPrefixElement(mutablebson::ConstElement elem) {
                 curr.rightSibling().ok() && curr.rightSibling().getFieldName() == "$id");
     } else {
         // Not an okay, $ prefixed field name.
-        const auto replaceWithHint =
-            serverGlobalParams.featureCompatibility.isVersionInitialized() &&
-                serverGlobalParams.featureCompatibility.isGreaterThanOrEqualTo(
-                    multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0)
-            ? "' is not allowed in the context of an update's replacement document. Consider using "
-              "an aggregation pipeline with $replaceWith."
-            : "' is not valid for storage.";
-
         uasserted(ErrorCodes::DollarPrefixedFieldName,
                   str::stream() << "The dollar ($) prefixed field '" << elem.getFieldName()
-                                << "' in '" << mutablebson::getFullName(elem) << replaceWithHint);
+                                << "' in '" << mutablebson::getFullName(elem)
+                                << "' is not allowed in the context of an update's replacement"
+                                   " document. Consider using an aggregation pipeline with"
+                                   " $replaceWith.");
     }
 }
 }  // namespace
@@ -137,10 +132,7 @@ Status storageValidIdField(const mongo::BSONElement& element) {
                               << "The '_id' value cannot be of type " << typeName(element.type()));
         case BSONType::Object: {
             auto status = element.Obj().storageValidEmbedded();
-            if (!status.isOK() && status.code() == ErrorCodes::DollarPrefixedFieldName &&
-                serverGlobalParams.featureCompatibility.isVersionInitialized() &&
-                serverGlobalParams.featureCompatibility.isGreaterThanOrEqualTo(
-                    multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0)) {
+            if (!status.isOK() && status.code() == ErrorCodes::DollarPrefixedFieldName) {
                 return Status(status.code(),
                               str::stream() << "_id fields may not contain '$'-prefixed fields: "
                                             << status.reason());
@@ -200,21 +192,16 @@ void scanDocument(mutablebson::ConstElement elem,
     // Only check top-level fields if 'allowTopLevelDollarPrefixes' is false, and don't validate any
     // fields for '$'-prefixes if 'allowTopLevelDollarPrefixes' is true.
     const bool checkTopLevelFields = !allowTopLevelDollarPrefixes && (recursionLevel == 1);
-    const bool dotsAndDollarsFeatureEnabled =
-        serverGlobalParams.featureCompatibility.isVersionInitialized() &&
-        serverGlobalParams.featureCompatibility.isGreaterThanOrEqualTo(
-            multiversion::FeatureCompatibilityVersion::kFullyDowngradedTo_5_0);
-    const bool checkFields = !dotsAndDollarsFeatureEnabled || checkTopLevelFields;
 
     auto fieldName = elem.getFieldName();
     if (fieldName[0] == '$') {
-        if (dotsAndDollarsFeatureEnabled && containsDotsAndDollarsField) {
+        if (containsDotsAndDollarsField) {
             *containsDotsAndDollarsField = true;
             // If we are not validating for storage, return once a $-prefixed field is found.
             if (!shouldValidate)
                 return;
         }
-        if (!childOfArray && checkFields && shouldValidate) {
+        if (!childOfArray && checkTopLevelFields && shouldValidate) {
             // Cannot start with "$", unless dbref.
             validateDollarPrefixElement(elem);
         }