# Test the complete path from plot specification to rendered data context("Plot building") df <- data.frame(x = 1:3, y = 3:1, z = letters[1:3]) test_that("there is one data frame for each layer", { nlayers <- function(x) length(ggplot_build(x)$data) l1 <- ggplot(df, aes(x, y)) + geom_point() l2 <- ggplot(df, aes(x, y)) + geom_point() + geom_line() l3 <- ggplot(df, aes(x, y)) + geom_point() + geom_line() + geom_point() expect_equal(nlayers(l1), 1) expect_equal(nlayers(l2), 2) expect_equal(nlayers(l3), 3) }) test_that("position aesthetics coerced to correct type", { l1 <- ggplot(df, aes(x, y)) + geom_point() d1 <- layer_data(l1, 1) expect_is(d1$x, "numeric") expect_is(d1$y, "numeric") l2 <- ggplot(df, aes(x, z)) + geom_point() + scale_x_discrete() d2 <- layer_data(l2, 1) expect_is(d2$x, "integer") expect_is(d2$y, "integer") }) test_that("non-position aesthetics are mapped", { l1 <- ggplot(df, aes(x, y, fill = z, colour = z, shape = z, size = z)) + geom_point() suppressWarnings(d1 <- layer_data(l1, 1)) expect_equal(sort(names(d1)), sort(c("x", "y", "fill", "group", "colour", "shape", "size", "PANEL", "alpha", "stroke"))) l2 <- l1 + scale_colour_manual(values = c("blue", "red", "yellow")) suppressWarnings(d2 <- layer_data(l2, 1)) expect_equal(d2$colour, c("blue", "red", "yellow")) }) test_that("strings are not converted to factors", { df <- data.frame(x = 1:2, y = 2:1, label = c("alpha", "beta"), stringsAsFactors = FALSE) p <- ggplot(df, aes(x, y)) + geom_text(aes(label = label), parse = TRUE) expect_is(layer_data(p)$label, "character") })