adds benchmark code for data frame functions (#72)

.Rbuildignore

@@ -12,3 +12,4 @@
 ^cran-comments\.md$
 ^CRAN-SUBMISSION$
 ^revdep$
+^bench$

bench/data-frame.R

@@ -0,0 +1,32 @@
+devtools::load_all(here::here())
+library(ggplot2)
+library(bench)
+
+print(mark(
+  dataframe(), # same as quick_df(NULL)
+  quick_df(),
+  quick_df(list()),
+
+  data.frame(),
+  data.frame(NULL),
+  data.frame(list())
+))
+
+autoplot(.Last.value)
+
+print(mark(
+  dataframe(a = integer(), b = character(), ),
+  data.frame(a = integer(), b = character())
+))
+
+autoplot(.Last.value)
+
+local({
+  c <- b <- a <- seq_len(100)
+  print(mark(
+    dataframe(a = a, b = b, c = c, ),
+    data.frame(a = a, b = b, c = c)
+  ))
+})
+
+autoplot(.Last.value)