use [. instead of subset for qenv

Author: m7pr

DESCRIPTION

@@ -58,13 +58,13 @@ Collate:
     'qenv-concat.R'
     'qenv-constructor.R'
     'qenv-eval_code.R'
+    'qenv-extract.R'
     'qenv-get_code.R'
     'qenv-get_env.R'
     'qenv-get_var.R'
     'qenv-get_warnings.R'
     'qenv-join.R'
     'qenv-show.R'
-    'qenv-subset.R'
     'qenv-within.R'
     'teal.code-package.R'
     'utils-get_code_dependency.R'

NAMESPACE

@@ -1,5 +1,6 @@
 # Generated by roxygen2: do not edit by hand
 
+S3method("[",qenv)
 S3method("[[",qenv.error)
 S3method(within,qenv)
 S3method(within,qenv.error)
@@ -13,7 +14,6 @@ export(get_warnings)
 export(join)
 export(new_qenv)
 export(qenv)
-export(subset)
 exportClasses(qenv)
 exportMethods(show)
 importFrom(lifecycle,badge)

R/qenv-extract.R

@@ -0,0 +1,36 @@
+#' @rdname qenv
+#' @order 2
+#'
+#' @section Subsetting:
+#' `x[names]` subsets objects in `qenv` environment and limit the code to the necessary to build limited objects.
+#'
+#' @param names (`character`) names of objects included in `qenv` to subset
+#'
+#' @examples
+#'
+#' # Subsetting
+#' q <- qenv()
+#' q <- eval_code(q, "a <- 1;b<-2")
+#' q["a"]
+#' q[c("a", "b")]
+#'
+#' @export
+`[.qenv` <- function(x, names) {
+  checkmate::assert_class(names, "character")
+  names_in_env <- intersect(names, ls(get_env(x)))
+  if (!length(names_in_env)) {
+    return(qenv())
+  }
+
+  limited_code <- get_code(x, names = names_in_env)
+  indexes <- which(x@code %in% limited_code)
+
+  x@env <- list2env(mget(x = names_in_env, envir = get_env(x)))
+  x@code <- limited_code
+  x@id <- x@id[indexes]
+  x@warnings <- x@warnings[indexes]
+  x@messages <- x@messages[indexes]
+
+  x
+}
+

R/qenv-subset.R

@@ -1,41 +1,41 @@
-testthat::test_that("subset extract proper objects", {
+testthat::test_that("`[.` extracts proper objects", {
   q <- qenv()
   code <- c("x<-1", "a<-1;b<-2")
   q <- eval_code(q, code)
   object_names <- c("x", "a")
-  qs <- subset(q, names = object_names)
+  qs <- q[object_names]
   testthat::expect_true(all(ls(get_env(qs)) %in% object_names))
 })
 
-testthat::test_that("subset extract proper code", {
+testthat::test_that("`[.` extract proper code", {
   q <- qenv()
   code <- c("x<-1", "a<-1;b<-2")
   q <- eval_code(q, code)
   object_names <- c("x", "a")
-  qs <- subset(q, names = object_names)
+  qs <- q[object_names]
   testthat::expect_identical(
     qs@code,
     c("x <- 1", "a <- 1")
   )
 })
 
-testthat::test_that("subset preservers comments in the code", {
+testthat::test_that("`[.` preservers comments in the code", {
   q <- qenv()
   code <- c("x<-1 #comment", "a<-1;b<-2")
   q <- eval_code(q, code)
-  qs <- subset(q, names = c("x", "a"))
+  qs <- q[c("x", "a")]
   testthat::expect_identical(
     qs@code,
     c("x <- 1 #comment", "a <- 1")
   )
 })
 
-testthat::test_that("subset extract proper elements of @id, @warnings and @messages fiels", {
+testthat::test_that("`[.` extract proper elements of @id, @warnings and @messages fiels", {
   q <- qenv()
   code <-
     c("x<-1 #comment", "message('tiny message')", "a<-1;b<-2;warning('small warning')")
   q <- eval_code(q, code)
-  qs <- subset(q, names = c("x", "a"))
+  qs <- q[c("x", "a")]
 
   testthat::expect_identical(qs@id, q@id[c(1, 3)])
   testthat::expect_identical(qs@code, q@code[c(1, 3)])