Replace XML package with xml2

The XML functions were having trouble dealing with (changes in?) the
Japanese Yahoo Finance pages. Switch to xml2, especially since XML is
no longer actively maintained.

Fixes #310.

DESCRIPTION

@@ -11,7 +11,7 @@ Authors@R: c(
   )
 Depends: R (>= 3.2.0), xts(>= 0.9-0), zoo, TTR(>= 0.2), methods
 Imports: curl
-Suggests: DBI,RMySQL,RSQLite,timeSeries,XML,downloader,jsonlite(>= 1.1)
+Suggests: DBI,RMySQL,RSQLite,timeSeries,xml2,downloader,jsonlite(>= 1.1)
 Description: Specify, build, trade, and analyse quantitative financial trading strategies.
 LazyLoad: yes
 License: GPL-3

R/getSymbols.R

@@ -433,8 +433,8 @@ function(Symbols,env,return.class='xts',index.class="Date",
         if(!hasArg("verbose")) verbose <- FALSE
         if(!hasArg("auto.assign")) auto.assign <- TRUE
 
-        if(!requireNamespace("XML", quietly=TRUE))
-          stop("package:",dQuote("XML"),"cannot be loaded.")
+        if(!requireNamespace("xml2", quietly=TRUE))
+          stop("package:",dQuote("xml2"),"cannot be loaded.")
 
         yahoo.URL <- "https://info.finance.yahoo.co.jp/history/"
 
@@ -498,8 +498,8 @@ function(Symbols,env,return.class='xts',index.class="Date",
                                     "&p=",page,
                                     sep='')
 
-                fdoc <- XML::htmlParse(URL)
-                rows <- XML::xpathApply(fdoc, "//table[@class='boardFin yjSt marB6']//tr")
+                fdoc <- xml2::read_html(URL)
+                rows <- xml2::xml_find_all(fdoc, "//table[@class='boardFin yjSt marB6']//tr")
                 if (length(rows) <= 1) break
 
                 totalrows <- c(totalrows, rows)
@@ -515,19 +515,19 @@ function(Symbols,env,return.class='xts',index.class="Date",
             cols <- c('Open','High','Low','Close','Volume','Adjusted')
 
             firstrow <- totalrows[[1]]
-            cells <- XML::getNodeSet(firstrow, "th")
+            cells <- xml2::xml_find_all(firstrow, "th")
             if (length(cells) == 5) cols <- cols[-(5:6)]
 
             # Process from the start, for easier stocksplit management
             totalrows <- rev(totalrows)
             mat <- matrix(0, ncol=length(cols) + 1, nrow=0, byrow=TRUE)
             for(row in totalrows) {
-                cells <- XML::getNodeSet(row, "td")
+                cells <- xml2::xml_find_all(row, "td")
 
                 # 2 cells means it is a stocksplit row
                 # So extract stocksplit data and recalculate the matrix we have so far
                 if (length(cells) == 2 && length(cols) == 6 & nrow(mat) > 1) {
-                    ss.data <- as.numeric(na.omit(as.numeric(unlist(strsplit(XML::xmlValue(cells[[2]]), "[^0-9]+")))))
+                    ss.data <- as.numeric(na.omit(as.numeric(unlist(strsplit(xml2::xml_text(cells[[2]]), "[^0-9]+")))))
                     factor <- ss.data[2] / ss.data[1]
 
                     mat <- rbind(t(apply(mat[-nrow(mat),], 1, function(x) {
@@ -541,10 +541,10 @@ function(Symbols,env,return.class='xts',index.class="Date",
                 # \u5e74 = "year"
                 # \u6708 = "month"
                 # \u65e5 = "day"
-                date <- as.Date(XML::xmlValue(cells[[1]]), format="%Y\u5e74%m\u6708%d\u65e5")
+                date <- as.Date(xml2::xml_text(cells[[1]]), format="%Y\u5e74%m\u6708%d\u65e5")
                 entry <- c(date)
                 for(n in 2:length(cells)) {
-                    entry <- cbind(entry, as.numeric(gsub(",", "", XML::xmlValue(cells[[n]]))))
+                    entry <- cbind(entry, as.numeric(gsub(",", "", xml2::xml_text(cells[[n]]))))
                 }
 
                 mat <- rbind(mat, entry)