Print long spec declarations properly (#598)

Fixes #597

NEWS.md

@@ -1,5 +1,7 @@
 # readr 1.0.0.9000
 
+* Long spec declarations now print properly (#597).
+
 * parsing problems in `read_delim()` and `read_fwf()` when columns are skipped using col_types now report the correct column name (#573, @cb4ds)
 
 * `parse_time()` now correctly handles 12 AM/PM (#579).

R/col_types.R

@@ -135,7 +135,7 @@ format.col_spec <- function(x, n = Inf, condense = NULL, ...) {
     vapply(seq_along(cols),
       function(i) {
         col_funs <- sub("^collector_", "col_", class(cols[[i]])[[1]])
-        args <- vapply(cols[[i]], deparse, character(1))
+        args <- vapply(cols[[i]], deparse2, character(1), sep = "\n    ")
         args <- paste(names(args), args, sep = " = ", collapse = ", ")
 
         col_names <- names(cols)[[i]]

R/utils.R

@@ -15,3 +15,7 @@ show_progress <- function() {
   !interactive() || # not an interactive session
   !is.null(getOption("knitr.in.progress")) # Not actively knitting a document
 }
+
+deparse2 <- function(expr, ..., sep = "\n") {
+  paste(deparse(expr, ...), collapse = sep)
+}

tests/testthat/test-col-spec.R

@@ -217,3 +217,12 @@ test_that("non-syntatic names are escaped", {
 )
 ")
 })
+
+test_that("long expressions are wrapped (597)", {
+  expect_equal(format(cols(a = col_factor(levels = c("apple", "pear", "banana", "peach", "apricot", "orange", "plum"), ordered = TRUE))),
+'cols(
+  a = col_factor(levels = c("apple", "pear", "banana", "peach", "apricot", "orange", "plum"
+    ), ordered = TRUE)
+)
+')
+})