tradeStats() doesn't honor Dates

[joshuaulrich]

Passing a Dates value to tradeStats() doesn't affect the output; the entire period is always returned.

Reproducible example:

library(blotter)
demo("longtrend")
tradeStats("longtrend")
tradeStats("longtrend", Dates = "2018")

Here's a patch that seems to work. But I didn't thoroughly check the output.

diff --git a/R/tradeStats.R b/R/tradeStats.R
index 9456387..0370fa2 100644
--- a/R/tradeStats.R
+++ b/R/tradeStats.R
@@ -148,6 +148,9 @@ tradeStats <- function( Portfolios
     
     use <- use[1] #use the first(default) value only if user hasn't specified
     tradeDef <- tradeDef[1]
+    if (is.null(Dates)) {
+        Dates <- "/"
+    }
     for (Portfolio in Portfolios){
         pname <- Portfolio
         Portfolio<-.getPortfolio(pname, envir=envir)
@@ -157,8 +160,8 @@ tradeStats <- function( Portfolios
         
         ## Trade Statistics
         for (symbol in symbols){
-            txn   <- Portfolio$symbols[[symbol]]$txn
-            posPL <- Portfolio$symbols[[symbol]]$posPL
+            txn   <- Portfolio$symbols[[symbol]]$txn[Dates]
+            posPL <- Portfolio$symbols[[symbol]]$posPL[Dates]
             posPL <- posPL[-1,]
 
             # Use gross transaction P&L to identify transactions that realized
@@ -192,7 +195,7 @@ tradeStats <- function( Portfolios
                        #moved above for daily stats for now
                    },
                    trades = {
-                       trades <- perTradeStats(pname,symbol,tradeDef=tradeDef, envir=envir)
+                       trades <- perTradeStats(pname,symbol,tradeDef=tradeDef, envir=envir, Dates=Dates)
                        PL.gt0 <- trades$Net.Trading.PL[trades$Net.Trading.PL  > 0]
                        PL.lt0 <- trades$Net.Trading.PL[trades$Net.Trading.PL  < 0]
                        PL.ne0 <- trades$Net.Trading.PL[trades$Net.Trading.PL != 0]