Do not use alias name as key for command info cache to fix the problem where UseCorrectCasing corrects aliases (#1216)

* Do not use alias name as key for command info cache to fix the problem where UseCorrectCasing corrects aliases

* Remove unused aliasName parameter and left-over GetCommandInfoInternal function from refactoring a few weeks ago

Author: bergmeister

Engine/CommandInfoCache.cs

@@ -30,19 +30,16 @@ public CommandInfoCache(Helper pssaHelperInstance)
         /// Retrieve a command info object about a command.
         /// </summary>
         /// <param name="commandName">Name of the command to get a commandinfo object for.</param>
-        /// <param name="aliasName">The alias of the command to be used in the cache key. If not given, uses the command name.</param>
         /// <param name="commandTypes">What types of command are needed. If omitted, all types are retrieved.</param>
         /// <returns></returns>
-        public CommandInfo GetCommandInfo(string commandName, string aliasName = null, CommandTypes? commandTypes = null)
+        public CommandInfo GetCommandInfo(string commandName, CommandTypes? commandTypes = null)
         {
             if (string.IsNullOrWhiteSpace(commandName))
             {
                 return null;
             }
 
-            // If alias name is given, we store the entry under that, but search with the command name
-            var key = new CommandLookupKey(aliasName ?? commandName, commandTypes);
-
+            var key = new CommandLookupKey(commandName, commandTypes);
             // Atomically either use PowerShell to query a command info object, or fetch it from the cache
             return _commandInfoCache.GetOrAdd(key, new Lazy<CommandInfo>(() => GetCommandInfoInternal(commandName, commandTypes))).Value;
         }
@@ -60,7 +57,7 @@ public CommandInfo GetCommandInfoLegacy(string commandOrAliasName, CommandTypes?
 
             return string.IsNullOrEmpty(commandName)
                 ? GetCommandInfo(commandOrAliasName, commandTypes: commandTypes)
-                : GetCommandInfo(commandName, aliasName: commandOrAliasName, commandTypes: commandTypes);
+                : GetCommandInfo(commandName, commandTypes: commandTypes);
         }
 
         /// <summary>

Engine/Helper.cs

@@ -402,7 +402,7 @@ public HashSet<string> GetExportedFunction(Ast ast)
             IEnumerable<Ast> cmdAsts = ast.FindAll(item => item is CommandAst
                 && exportFunctionsCmdlet.Contains((item as CommandAst).GetCommandName(), StringComparer.OrdinalIgnoreCase), true);
 
-            CommandInfo exportMM = Helper.Instance.GetCommandInfoLegacy("export-modulemember", CommandTypes.Cmdlet);
+            CommandInfo exportMM = Helper.Instance.GetCommandInfo("export-modulemember", CommandTypes.Cmdlet);
 
             // switch parameters
             IEnumerable<ParameterMetadata> switchParams = (exportMM != null) ? exportMM.Parameters.Values.Where<ParameterMetadata>(pm => pm.SwitchParameter) : Enumerable.Empty<ParameterMetadata>();
@@ -661,31 +661,6 @@ public bool PositionalParameterUsed(CommandAst cmdAst, bool moreThanTwoPositiona
             return moreThanTwoPositional ? argumentsWithoutProcedingParameters > 2 : argumentsWithoutProcedingParameters > 0;
         }
 
-
-        /// <summary>
-        /// Get a CommandInfo object of the given command name
-        /// </summary>
-        /// <returns>Returns null if command does not exists</returns>
-        private CommandInfo GetCommandInfoInternal(string cmdName, CommandTypes? commandType)
-        {
-            using (var ps = System.Management.Automation.PowerShell.Create())
-            {
-                var psCommand = ps.AddCommand("Get-Command")
-                    .AddParameter("Name", cmdName)
-                    .AddParameter("ErrorAction", "SilentlyContinue");
-
-                if(commandType!=null)
-                {
-                    psCommand.AddParameter("CommandType", commandType);
-                }
-
-                var commandInfo = psCommand.Invoke<CommandInfo>()
-                         .FirstOrDefault();
-
-                return commandInfo;
-            }
-        }
-
         /// <summary>
         ///  Legacy method, new callers should use <see cref="GetCommandInfo"/> instead.
         ///  Given a command's name, checks whether it exists. It does not use the passed in CommandTypes parameter, which is a bug.