Fix multiline commands in RUN not being concatenated together by &&.

Close #4 and Close #5 (h/t @nathansam)

Author: coatless

R/dockerfile-instructions.R

@@ -87,7 +87,10 @@ dfi_from <- function(dockerfile, image, as = NULL) {
 #' @export
 dfi_run <- function(dockerfile, commands) {
   check_dockerfile(dockerfile)
-  add_dockerfile_line(dockerfile, "RUN", commands)
+    
+  # Join multiple commands with &&
+  command_str <- paste(commands, collapse = " && ")
+  add_dockerfile_line(dockerfile, "RUN", command_str)
 }
 
 #' Add a `COPY` instruction to a `dockerfile`

tests/testthat/test-dockerfile-instructions.R

@@ -26,8 +26,7 @@ test_that("dfi_run(): adds RUN instruction correctly", {
 
   # Multiple commands
   df <- dfi_run(df, c("apt-get update", "apt-get install -y curl"))
-  expect_equal(df$lines[2], "RUN apt-get update")
-  expect_equal(df$lines[3], "    apt-get install -y curl")
+  expect_equal(df$lines[2], "RUN apt-get update && apt-get install -y curl")
 })
 
 # Test dfi_copy() ----