In qplot, look up layer in ggplot2 package env (#2590)

Fixes #2586. Regression introduced in 4c1964b

Author: hadley

R/quick-plot.r

@@ -144,7 +144,7 @@ qplot <- function(x, y, ..., data, facets = NULL, margins = FALSE,
   for (g in geom) {
     # We reevaluate constants once per geom for historical reasons?
     params <- lapply(consts, rlang::eval_tidy)
-    p <- p + do.call(paste0("geom_", g), params, envir = caller_env)
+    p <- p + do.call(paste0("geom_", g), params)
   }
 
   logv <- function(var) var %in% strsplit(log, "")[[1]]

tests/testthat/test-qplot.r

@@ -29,3 +29,12 @@ test_that("qplot() evaluates constants in the right place", {
   })
   expect_identical(layer_data(p)$colour, I("red"))
 })
+
+test_that("qplot() evaluates layers in package environment", {
+  geom_line <- function(...) {
+    stop("!!!")
+  }
+
+  expect_error(p <- qplot(1, 1, geom = "line"), NA)
+
+})