SERVER-42585 use 4.2 mongos commands as a last stable binary commands

Author: Misha Tyulenev

jstests/sharding/database_and_shard_versioning_all_commands.js

@@ -438,8 +438,8 @@ let testCases = {
     whatsmyuri: {skip: "executes locally on mongos (not sent to any remote node)"},
 };
 
-commandsRemovedFromMongosIn42.forEach(function(cmd) {
-    testCases[cmd] = {skip: "must define test coverage for 4.0 backwards compatibility"};
+commandsRemovedFromMongosIn44.forEach(function(cmd) {
+    testCases[cmd] = {skip: "must define test coverage for 4.2 backwards compatibility"};
 });
 
 class TestRunner {
@@ -574,18 +574,15 @@ class TestRunner {
         // After iterating through all the existing commands, ensure there were no additional
         // test cases that did not correspond to any mongos command.
         for (let key of Object.keys(testCases)) {
-            // We have defined real test cases for commands added in 4.2/4.4 so that the test
+            // We have defined real test cases for commands added in 4.4 so that the test
             // cases are exercised in the regular suites, but because these test cases can't
             // run in the last stable suite, we skip processing them here to avoid failing the
-            // below assertion. We have defined "skip" test cases for commands removed in 4.2
+            // below assertion. We have defined "skip" test cases for commands removed in 4.4
             // so the test case is defined in last stable suites (in which these commands still
             // exist on the mongos), but these test cases won't be run in regular suites, so we
             // skip processing them below as well.
-            if (commandsAddedToMongosIn42.includes(key) ||
-                commandsRemovedFromMongosIn42.includes(key)) {
-                continue;
-            }
-            if (commandsAddedToMongosIn44.includes(key)) {
+            if (commandsAddedToMongosIn44.includes(key) ||
+                commandsRemovedFromMongosIn44.includes(key)) {
                 continue;
             }
             assert(testCases[key].validated || testCases[key].conditional,

jstests/sharding/libs/last_stable_mongos_commands.js

@@ -1,26 +1,10 @@
-// These commands were removed from mongos 4.2, but will still appear in the listCommands output
-// of a 4.0 mongos. A last-stable mongos will be unable to run a command on a latest version shard
+// These commands were removed from mongos 4.4, but will still appear in the listCommands output
+// of a 4.2 mongos. A last-stable mongos will be unable to run a command on a latest version shard
 // that no longer supports that command. To increase test coverage and allow us to run on same- and
 // mixed-version suites, we allow these commands to have a test defined without always existing on
 // the servers being used.
-const commandsRemovedFromMongosIn42 = [
-    'copydb',
-    'copydbsaslstart',
-    'eval',
-    'geoNear',
-    'getPrevError',
-    'group',
-    'reIndex',
-];
-// These commands were added in mongos 4.2/4.4, so will not appear in the listCommands output of a
-// 4.0 mongos. We will allow these commands to have a test defined without always existing on the
+const commandsRemovedFromMongosIn44 = [];
+// These commands were added in mongos 4.4, so will not appear in the listCommands output of a
+// 4.2 mongos. We will allow these commands to have a test defined without always existing on the
 // mongos being used.
-const commandsAddedToMongosIn42 = [
-    'abortTransaction',
-    'commitTransaction',
-    'dropConnections',
-    'setIndexCommitQuorum',
-    'startRecordingTraffic',
-    'stopRecordingTraffic',
-];
-const commandsAddedToMongosIn44 = ['refineCollectionShardKey'];
+const commandsAddedToMongosIn44 = ['refineCollectionShardKey'];

jstests/sharding/safe_secondary_reads_drop_recreate.js

@@ -305,8 +305,8 @@ let testCases = {
     whatsmyuri: {skip: "does not return user data"}
 };
 
-commandsRemovedFromMongosIn42.forEach(function(cmd) {
-    testCases[cmd] = {skip: "must define test coverage for 4.0 backwards compatibility"};
+commandsRemovedFromMongosIn44.forEach(function(cmd) {
+    testCases[cmd] = {skip: "must define test coverage for 4.2 backwards compatibility"};
 });
 
 let scenarios = {

jstests/sharding/safe_secondary_reads_single_migration_suspend_range_deletion.js

@@ -340,8 +340,8 @@ let testCases = {
     whatsmyuri: {skip: "does not return user data"}
 };
 
-commandsRemovedFromMongosIn42.forEach(function(cmd) {
-    testCases[cmd] = {skip: "must define test coverage for 4.0 backwards compatibility"};
+commandsRemovedFromMongosIn44.forEach(function(cmd) {
+    testCases[cmd] = {skip: "must define test coverage for 4.2 backwards compatibility"};
 });
 
 // Set the secondaries to priority 0 and votes 0 to prevent the primaries from stepping down.

jstests/sharding/safe_secondary_reads_single_migration_waitForDelete.js

@@ -310,8 +310,8 @@ let testCases = {
     whatsmyuri: {skip: "does not return user data"}
 };
 
-commandsRemovedFromMongosIn42.forEach(function(cmd) {
-    testCases[cmd] = {skip: "must define test coverage for 4.0 backwards compatibility"};
+commandsRemovedFromMongosIn44.forEach(function(cmd) {
+    testCases[cmd] = {skip: "must define test coverage for 4.2 backwards compatibility"};
 });
 
 // Set the secondaries to priority 0 and votes 0 to prevent the primaries from stepping down.