Fix bug in Tables.getcolumn(t::TableSelection, i::Int) (#150)

Author: eliascarv

src/tableselection.jl

@@ -43,7 +43,7 @@ Tables.columnnames(t::TableSelection) = t.names
 
 function Tables.getcolumn(t::TableSelection, i::Int)
   i > t.ncols && error("Table has no column with index $i.")
-  Tables.getcolumn(t.cols, t.names[i])
+  Tables.getcolumn(t.cols, t.mapnames[t.names[i]])
 end
 
 function Tables.getcolumn(t::TableSelection, nm::Symbol)

test/tableselection.jl

@@ -36,6 +36,9 @@
     @test Tables.getcolumn(s, :x) == t.c
     @test Tables.getcolumn(s, :y) == t.d
     @test Tables.getcolumn(s, :z) == t.f
+    @test Tables.getcolumn(s, 1)  == t.c
+    @test Tables.getcolumn(s, 2)  == t.d
+    @test Tables.getcolumn(s, 3)  == t.f
 
     # row table
     select = [:a, :b, :e]