fix warning in mipLineHistorical

R/mipLineHistorical.R

@@ -256,8 +256,17 @@ mipLineHistorical <- function(x,x_hist=NULL,color.dim="identifier",linetype.dim=
     #fill: add colors for historical and keep shape symbol
     #alpha: add colors for projection depending on leg.proj
     p <- p + scale_color_manual(color.dim.name,values = color_set, breaks=model_output,labels=model_output,guide=guide_legend(order=1,title.position = "top", ncol=legend.ncol))
-    p <- p + scale_fill_manual("Historical data",values = color_set[historical],breaks=historical,
-                               guide=guide_legend(override.aes = list(colour=color_set[historical],shape="+",linetype=0,size=5),order=2,title.position = "top", ncol=legend.ncol))
+
+    if (!is.null(x_hist)) {
+      p <- p + scale_fill_manual("Historical data",
+        values = color_set[historical], breaks = historical,
+        guide = guide_legend(override.aes = list(
+          colour = color_set[historical],
+          shape = "+", linetype = 0, size = 5
+        ), order = 2, title.position = "top", ncol = legend.ncol)
+      )
+    }
+
     if(leg.proj) p <- p + scale_alpha_manual("Other projections",values = seq(0.1,1,length.out = length(projection)),breaks=projection,labels=projection,guide=guide_legend(override.aes = list(colour=color_set[projection],shape=NULL,linetype=1,linewidth=1,alpha=0.5),order=3,title.position = "top", ncol=legend.ncol))
     else p <- p + scale_alpha_manual("Other projections",values = seq(0.1,1,length.out = length(projection)),breaks=projection,labels=projection,guide=guide_legend(override.aes = list(colour="#A1A194",shape=NULL,linetype=1,linewidth=1,alpha=0.5),order=3,title.position = "top", ncol=legend.ncol))
     p <- p + guides(linetype=guide_legend(order=4,title.position="top",ncol=legend.ncol))