Move quasi_label to its own file

Author: hadley

DESCRIPTION

@@ -69,6 +69,7 @@ Collate:
     'mock.R'
     'old-school.R'
     'praise.R'
+    'quasi-label.R'
     'recover.R'
     'reporter-check.R'
     'reporter-debug.R'

R/expectation.R

@@ -63,83 +63,6 @@ expectation <- function(type, message, srcref = NULL) {
 #' @param x object to test for class membership
 is.expectation <- function(x) inherits(x, "expectation")
 
-#' Quasi-labelling
-#'
-#' The first argument to every `expect_` function can use unquoting to
-#' construct better labels. This makes it easy to create informative labels
-#' expectations are used inside a function or a for loop. `quasi_label()` wraps
-#' up the details, returning the expression and label.
-#'
-#' @section Limitations:
-#' Because all `expect_` function use unquoting to generate more informative
-#' labels, you can not use unquoting for other purposes. Instead, you'll need
-#' to perform all other unquoting outside of the expectation and only test
-#' the results.
-#'
-#' @param quo A quosure created by `rlang::enquo()`.
-#' @param label An optional label to override the default. This is
-#'   only provided for internal usage. Modern expectations should not
-#'   include a `label` parameter.
-#' @param arg Argument name shown in error message if `quo` is missing.
-#' @keywords internal
-#' @return A list containing two elements:
-#' \item{val}{The evaluate value of `quo`}
-#' \item{lab}{The quasiquoted label generated from `quo`}
-#' @export
-#' @examples
-#' f <- function(i) if (i > 3) i * 9 else i * 10
-#' i <- 10
-#'
-#' # This short of expression commonly occurs inside a for loop or function
-#' # And the failure isn't helpful because you can't see the value of i
-#' # that caused the problem:
-#' show_failure(expect_equal(f(i), i * 10))
-#'
-#' # To overcome this issue, testthat allows you to unquote expressions using
-#' # !!. This causes the failure message to show the value rather than the
-#' # variable name
-#' show_failure(expect_equal(f(!!i), !!(i * 10)))
-quasi_label <- function(quo, label = NULL, arg = "quo") {
-  force(quo)
-  if (quo_is_missing(quo)) {
-    stop("argument `", arg, "` is missing, with no default.", call. = FALSE)
-  }
-
-  list(
-    val = eval_bare(get_expr(quo), get_env(quo)),
-    lab = label %||% expr_label(get_expr(quo))
-  )
-}
-
-quasi_capture <- function(.quo, .label, .capture, ...) {
-  act <- list()
-  act$lab <- .label %||% quo_label(.quo)
-  act$cap <- .capture(act$val <- eval_bare(get_expr(.quo), get_env(.quo)), ...)
-
-  act
-}
-
-expr_label <- function(x) {
-  if (is.character(x)) {
-    encodeString(x, quote = '"')
-  } else if (is.atomic(x)) {
-    format(x)
-  } else if (is.name(x)) {
-    paste0("`", as.character(x), "`")
-  } else {
-    chr <- deparse(x)
-    if (length(chr) > 1) {
-      if (identical(x[[1]], quote(`function`))) {
-        x[[3]] <- quote(...)
-        chr <- paste(deparse(x), collapse = "\n")
-      } else {
-        chr <- paste(deparse(as.call(list(x[[1]], quote(...)))), collapse = "\n")
-      }
-    }
-    chr
-  }
-}
-
 expectation_type <- function(exp) {
   stopifnot(is.expectation(exp))
   gsub("^expectation_", "", class(exp)[[1]])

R/quasi-label.R

@@ -0,0 +1,76 @@
+#' Quasi-labelling
+#'
+#' The first argument to every `expect_` function can use unquoting to
+#' construct better labels. This makes it easy to create informative labels
+#' expectations are used inside a function or a for loop. `quasi_label()` wraps
+#' up the details, returning the expression and label.
+#'
+#' @section Limitations:
+#' Because all `expect_` function use unquoting to generate more informative
+#' labels, you can not use unquoting for other purposes. Instead, you'll need
+#' to perform all other unquoting outside of the expectation and only test
+#' the results.
+#'
+#' @param quo A quosure created by `rlang::enquo()`.
+#' @param label An optional label to override the default. This is
+#'   only provided for internal usage. Modern expectations should not
+#'   include a `label` parameter.
+#' @param arg Argument name shown in error message if `quo` is missing.
+#' @keywords internal
+#' @return A list containing two elements:
+#' \item{val}{The evaluate value of `quo`}
+#' \item{lab}{The quasiquoted label generated from `quo`}
+#' @export
+#' @examples
+#' f <- function(i) if (i > 3) i * 9 else i * 10
+#' i <- 10
+#'
+#' # This short of expression commonly occurs inside a for loop or function
+#' # And the failure isn't helpful because you can't see the value of i
+#' # that caused the problem:
+#' show_failure(expect_equal(f(i), i * 10))
+#'
+#' # To overcome this issue, testthat allows you to unquote expressions using
+#' # !!. This causes the failure message to show the value rather than the
+#' # variable name
+#' show_failure(expect_equal(f(!!i), !!(i * 10)))
+quasi_label <- function(quo, label = NULL, arg = "quo") {
+  force(quo)
+  if (quo_is_missing(quo)) {
+    stop("argument `", arg, "` is missing, with no default.", call. = FALSE)
+  }
+
+  list(
+    val = eval_bare(get_expr(quo), get_env(quo)),
+    lab = label %||% expr_label(get_expr(quo))
+  )
+}
+
+quasi_capture <- function(.quo, .label, .capture, ...) {
+  act <- list()
+  act$lab <- .label %||% quo_label(.quo)
+  act$cap <- .capture(act$val <- eval_bare(get_expr(.quo), get_env(.quo)), ...)
+
+  act
+}
+
+expr_label <- function(x) {
+  if (is.character(x)) {
+    encodeString(x, quote = '"')
+  } else if (is.atomic(x)) {
+    format(x)
+  } else if (is.name(x)) {
+    paste0("`", as.character(x), "`")
+  } else {
+    chr <- deparse(x)
+    if (length(chr) > 1) {
+      if (identical(x[[1]], quote(`function`))) {
+        x[[3]] <- quote(...)
+        chr <- paste(deparse(x), collapse = "\n")
+      } else {
+        chr <- paste(deparse(as.call(list(x[[1]], quote(...)))), collapse = "\n")
+      }
+    }
+    chr
+  }
+}