Simplify variant test (#1610)

And report variant name when adding file snapshot

Author: hadley

R/snapshot-file.R

@@ -166,7 +166,7 @@ snapshot_review_hint <- function(test, name, ci = on_ci(), check = in_rcmd_check
   )
 }
 
-snapshot_file_equal <- function(snap_test_dir, snap_name, path, file_equal = compare_file_binary, fail_on_new = FALSE, trace_env = NULL) {
+snapshot_file_equal <- function(snap_test_dir, snap_name, snap_variant, path, file_equal = compare_file_binary, fail_on_new = FALSE, trace_env = NULL) {
   if (!file.exists(path)) {
     abort(paste0("`", path, "` not found"))
   }
@@ -187,7 +187,11 @@ snapshot_file_equal <- function(snap_test_dir, snap_name, path, file_equal = com
     dir.create(snap_test_dir, showWarnings = FALSE, recursive = TRUE)
     file.copy(path, cur_path)
 
-    message <- paste0("Adding new file snapshot: 'tests/testhat/_snaps/", snap_name, "'")
+    message <- paste0(
+      "Adding new file snapshot: 'tests/testhat/_snaps/",
+      snap_variant, if (!is.null(snap_variant)) "/",
+      snap_name, "'"
+    )
     if (fail_on_new) {
       fail(message, trace_env = trace_env)
     } else {

R/snapshot-reporter.R

@@ -101,6 +101,7 @@ SnapshotReporter <- R6::R6Class("SnapshotReporter",
       snapshot_file_equal(
         snap_test_dir = snap_dir,
         snap_name = name,
+        snap_variant = variant,
         path = path,
         file_equal = file_equal,
         fail_on_new = self$fail_on_new,

tests/testthat/_snaps/R4.0/snapshot-file/nickname.txt

@@ -0,0 +1 @@
+R4.0

tests/testthat/_snaps/R4.0/snapshot-file/version.txt

@@ -1,7 +1,7 @@
-# can access nickname
+# variants save different values
 
     Code
-      version$nickname
+      r_version()
     Output
-      [1] "Shake and Throw"
+      [1] "R4.0"
 

tests/testthat/_snaps/R4.0/snapshot.md

@@ -0,0 +1 @@
+R4.1

tests/testthat/_snaps/R4.1/snapshot-file/nickname.txt

@@ -1,7 +1,7 @@
-# can access nickname
+# variants save different values
 
     Code
-      version$nickname
+      r_version()
     Output
-      [1] "Bird Hippie"
+      [1] "R4.1"
 

tests/testthat/_snaps/R4.1/snapshot-file/version.txt

@@ -48,8 +48,8 @@ test_that("expect_snapshot_file works in a different directory", {
 
 test_that("expect_snapshot_file works with variant", {
   expect_snapshot_file(
-    write_tmp_lines(version$nickname),
-    "nickname.txt",
+    write_tmp_lines(r_version()),
+    "version.txt",
     compare = compare_file_text,
     variant = r_version()
   )
@@ -96,35 +96,35 @@ test_that("warns on first creation", {
 
   # Warns on first run
   expect_warning(
-    expect_true(snapshot_file_equal(tempdir(), "test.txt", path)),
+    expect_true(snapshot_file_equal(tempdir(), "test.txt", NULL, path)),
     "new file snapshot"
   )
 
   # Errors on non-existing file
   expect_error(
-    expect_true(snapshot_file_equal(tempdir(), "test.txt", "doesnt-exist.txt")),
+    expect_true(snapshot_file_equal(tempdir(), "test.txt", NULL, "doesnt-exist.txt")),
     "`doesnt-exist.txt` not found"
   )
 
 
   # Unchanged returns TRUE
-  expect_true(snapshot_file_equal(tempdir(), "test.txt", path))
+  expect_true(snapshot_file_equal(tempdir(), "test.txt", NULL, path))
   expect_true(file.exists(file.path(tempdir(), "test.txt")))
   expect_false(file.exists(file.path(tempdir(), "test.new.txt")))
 
   # Changed returns FALSE
   path2 <- write_tmp_lines("b")
-  expect_false(snapshot_file_equal(tempdir(), "test.txt", path2))
+  expect_false(snapshot_file_equal(tempdir(), "test.txt", NULL, path2))
   expect_true(file.exists(file.path(tempdir(), "test.txt")))
   expect_true(file.exists(file.path(tempdir(), "test.new.txt")))
 
   # Changing again overwrites
   path2 <- write_tmp_lines("c")
-  expect_false(snapshot_file_equal(tempdir(), "test.txt", path2))
+  expect_false(snapshot_file_equal(tempdir(), "test.txt", NULL, path2))
   expect_equal(brio::read_lines(file.path(tempdir(), "test.new.txt")), "c")
 
   # Unchanged cleans up
-  expect_true(snapshot_file_equal(tempdir(), "test.txt", path))
+  expect_true(snapshot_file_equal(tempdir(), "test.txt", NULL, path))
   expect_true(file.exists(file.path(tempdir(), "test.txt")))
   expect_false(file.exists(file.path(tempdir(), "test.new.txt")))
 })

tests/testthat/_snaps/R4.1/snapshot.md

@@ -1,5 +1,5 @@
-test_that("can access nickname", {
-  expect_snapshot(version$nickname, variant = r_version())
+test_that("variants save different values", {
+  expect_snapshot(r_version(), variant = r_version())
 })
 
 test_that("can snapshot output", {