Better way to ignore attributes when comparing TRUE/FALSE (#2011)

Fixes #1996

Author: hadley

NEWS.md

@@ -1,5 +1,6 @@
 # testthat (development version)
 
+* `expect_true()` and `expect_false()` give better errors if `actual` isn't a vector (#1996).
 * `expect_no_*()` expectations no longer incorrectly emit a passing test result if they in fact fail (#1997).
 * Require the latest version of waldo (0.6.0) in order to get the latest goodies (#1955).
 * `expect_visible()` and `expect_invisible()` have improved failure messages (#1966).

R/expect-constant.R

@@ -1,5 +1,6 @@
 #' Does code return `TRUE` or `FALSE`?
 #'
+#' @description
 #' These are fall-back expectations that you can use when none of the other
 #' more specific expectations apply. The disadvantage is that you may get
 #' a less informative error message.
@@ -30,18 +31,14 @@ NULL
 #' @rdname logical-expectations
 expect_true <- function(object, info = NULL, label = NULL) {
   act <- quasi_label(enquo(object), label, arg = "object")
-  act$val <- as.vector(act$val)
-
-  expect_waldo_constant(act, TRUE, info = info)
+  expect_waldo_constant(act, TRUE, info = info, ignore_attr = TRUE)
 }
 
 #' @export
 #' @rdname logical-expectations
 expect_false <- function(object, info = NULL, label = NULL) {
   act <- quasi_label(enquo(object), label, arg = "object")
-  act$val <- as.vector(act$val)
-
-  expect_waldo_constant(act, FALSE, info = info)
+  expect_waldo_constant(act, FALSE, info = info, ignore_attr = TRUE)
 }
 
 #' Does code return `NULL`?
@@ -66,11 +63,17 @@ expect_null <- function(object, info = NULL, label = NULL) {
 
 # helpers -----------------------------------------------------------------
 
-expect_waldo_constant <- function(act, constant, info) {
-  comp <- waldo_compare(act$val, constant, x_arg = "actual", y_arg = "expected")
+expect_waldo_constant <- function(act, constant, info, ...) {
+  comp <- waldo_compare(
+    act$val,
+    constant,
+    x_arg = "actual",
+    y_arg = "expected",
+    ...
+  )
 
   expect(
-    identical(act$val, constant),
+    length(comp) == 0,
     sprintf(
       "%s is not %s\n\n%s",
       act$lab, deparse(constant),

man/logical-expectations.Rd

@@ -12,6 +12,13 @@
     `actual`:   TRUE 
     `expected`: FALSE
 
+# can compare non-vectors
+
+    quote(x) is not TRUE
+    
+    `actual` is a symbol
+    `expected` is a logical vector (TRUE)
+
 # expect_null works
 
     1L is not NULL

tests/testthat/_snaps/expect-constant.md

@@ -1,13 +1,13 @@
 # produces consistent output
 
     1: expect_true(FALSE)
-    2: expect_waldo_constant(act, TRUE, info = info)
-    3: expect(identical(act$val, constant), sprintf("%s is not %s\n\n%s", act$lab,
+    2: expect_waldo_constant(act, TRUE, info = info, ignore_attr = TRUE)
+    3: expect(length(comp) == 0, sprintf("%s is not %s\n\n%s", act$lab, deparse(co
 
     1: f()
     2: expect_true(FALSE)
-    3: expect_waldo_constant(act, TRUE, info = info)
-    4: expect(identical(act$val, constant), sprintf("%s is not %s\n\n%s", act$lab,
+    3: expect_waldo_constant(act, TRUE, info = info, ignore_attr = TRUE)
+    4: expect(length(comp) == 0, sprintf("%s is not %s\n\n%s", act$lab, deparse(co
 
     1: stop("stop")
 

tests/testthat/_snaps/reporter-debug.md

@@ -13,6 +13,11 @@ test_that("logical tests ignore attributes", {
   expect_success(expect_false(c(a = FALSE)))
 })
 
+test_that("can compare non-vectors", {
+  local_output_override()
+  expect_snapshot_failure(expect_true(quote(x)))
+})
+
 test_that("additional info returned in message", {
   expect_failure(expect_true(FALSE, "NOPE"), "\nNOPE")
   expect_failure(expect_false(TRUE, "YUP"), "\nYUP")
@@ -25,4 +30,3 @@ test_that("expect_null works", {
   expect_snapshot_failure(expect_null(1L))
   expect_snapshot_failure(expect_null(environment()))
 })
-