Resubmission of #143 (#145)

r-lib · Dec 11, 2018 · 7f30784 · 7f30784
1 parent 852c428
commit 7f30784
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Showing 2 changed files with 8 additions and 1 deletion.
diff --git a/R/size.R b/R/size.R
@@ -108,7 +108,7 @@ vec_slice <- function(x, i) {
     NULL
   } else if (is.data.frame(x)) {
     # Much faster, and avoids creating rownames
-    out <- lapply(x, `[`, i)
+    out <- lapply(x, vec_slice, i)
     vec_restore(out, x)
   } else if (is_vector(x)) {
     d <- vec_dims(x)

diff --git a/tests/testthat/test-size.R b/tests/testthat/test-size.R
@@ -49,6 +49,13 @@ test_that("can subset object of any dimensionality", {
   expect_equal(vec_slice(x4, 1L), ones(1, 3, 4, 5))
 })
 
+test_that("can subset data frame columns", {
+  df <- data.frame(x = 1:2)
+  df$y <- data.frame(a = 2:1)
+
+  expect_equal(vec_slice(df, 1L)$y, vec_slice(df$y, 1L))
+})
+
 test_that("can modify subset", {
   x1 <- c(2, 1)
   vec_slice(x1, 1L) <- 1