From fc9c75056cdfdd741f4841ad12d3fc4e140003bd Mon Sep 17 00:00:00 2001
From: Hadley Wickham <h.wickham@gmail.com>
Date: Thu, 7 Aug 2025 08:22:57 -0400
Subject: [PATCH] More informative `expect_match()` when object is a vector

Fixes #2181
---
 NEWS.md                                |  2 +-
 R/expect-match.R                       | 17 ++++++++++++++---
 R/expect-output.R                      |  2 +-
 tests/testthat/_snaps/expect-match.md  | 18 ++++++++++++------
 tests/testthat/_snaps/expect-output.md |  2 +-
 tests/testthat/test-expect-match.R     |  7 +++++--
 6 files changed, 34 insertions(+), 14 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index c049ea22e..dd2080f0e 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -19,7 +19,7 @@
 * `vignette("custom-expectations)` has been overhauled to make it much clearer how to create high-quality expectations (#2113, #2132, #2072).
 * `expect_snapshot()` and friends will now fail when creating a new snapshot on CI. This is usually a signal that you've forgotten to run it locally before committing (#1461).
 * `expect_snapshot_value()` can now handle expressions that generate `-` (#1678) or zero length atomic vectors (#2042).
-* `expect_matches()` failures should be a little easier to read (#2135).
+* `expect_matches()` failures should be a little easier to read (#2135, #2181).
 * New `local_on_cran(TRUE)` allows you to simulate how your tests will run on CRAN (#2112).
 * `expect_no_*()` now executes the entire code block, rather than stopping at the first message or warning (#1991).
 * `expect_no_failures()` and `expect_no_successes()` are now deprecated as `expect_success()` now test for no failures and `expect_failure()` tests for no successes (#)
diff --git a/R/expect-match.R b/R/expect-match.R
index d20cde158..d612f1cf9 100644
--- a/R/expect-match.R
+++ b/R/expect-match.R
@@ -106,6 +106,7 @@ expect_match_ <- function(
   info = NULL,
   label = NULL,
   negate = FALSE,
+  title = "Text",
   trace_env = caller_env()
 ) {
   matches <- grepl(regexp, act$val, perl = perl, fixed = fixed, ...)
@@ -118,14 +119,24 @@ expect_match_ <- function(
 
   text <- encodeString(act$val)
   if (length(act$val) == 1) {
-    values <- paste0('Text: "', text, '"')
+    values <- paste0(title, ': "', text, '"')
+    which <- ""
   } else {
-    values <- paste0("Text:\n", paste0("* ", text, collapse = "\n"))
+    bullet <- ifelse(
+      condition,
+      cli::col_green(cli::symbol$tick),
+      cli::col_red(cli::symbol$cross)
+    )
+    values <- paste0(title, ":\n", paste0(bullet, " ", text, collapse = "\n"))
+    which <- if (all) "Every element of " else "Some element of "
   }
+  match <- if (negate) "matches" else "does not match"
 
   msg <- sprintf(
-    if (negate) "%s matches %s %s.\n%s" else "%s does not match %s %s.\n%s",
+    "%s%s %s %s %s.\n%s",
+    which,
     act$lab,
+    match,
     if (fixed) "string" else "regexp",
     encodeString(regexp, quote = '"'),
     values
diff --git a/R/expect-output.R b/R/expect-output.R
index 9605e54f2..65c16e950 100644
--- a/R/expect-output.R
+++ b/R/expect-output.R
@@ -48,6 +48,6 @@ expect_output <- function(
     pass(act$val)
   } else {
     act <- labelled_value(act$cap, act$lab)
-    expect_match_(act, enc2native(regexp), ...)
+    expect_match_(act, enc2native(regexp), ..., title = "Output")
   }
 }
diff --git a/tests/testthat/_snaps/expect-match.md b/tests/testthat/_snaps/expect-match.md
index f966e6ee9..6e148e3e1 100644
--- a/tests/testthat/_snaps/expect-match.md
+++ b/tests/testthat/_snaps/expect-match.md
@@ -9,13 +9,19 @@
 
 ---
 
-    `many` does not match regexp "asdf".
+    Every element of `many` does not match regexp "a".
     Text:
-    * a
-    * b
-    * c
-    * d
-    * e
+    ✔ a
+    ✔ a
+    ✖ b
+
+---
+
+    Some element of `many` does not match regexp "c".
+    Text:
+    ✖ a
+    ✖ a
+    ✖ b
 
 # expect_match validates its inputs
 
diff --git a/tests/testthat/_snaps/expect-output.md b/tests/testthat/_snaps/expect-output.md
index 393572b7f..71af3d211 100644
--- a/tests/testthat/_snaps/expect-output.md
+++ b/tests/testthat/_snaps/expect-output.md
@@ -1,7 +1,7 @@
 # expect = string checks for match
 
     `g()` does not match regexp "x".
-    Text: "!"
+    Output: "!"
 
 ---
 
diff --git a/tests/testthat/test-expect-match.R b/tests/testthat/test-expect-match.R
index 47b30ee80..9e417c30d 100644
--- a/tests/testthat/test-expect-match.R
+++ b/tests/testthat/test-expect-match.R
@@ -1,12 +1,15 @@
 test_that("generates useful failure messages", {
+  local_reproducible_output(unicode = TRUE)
+
   zero <- character(0)
   expect_snapshot_failure(expect_match(zero, 'asdf'))
 
   one <- "bcde"
   expect_snapshot_failure(expect_match(one, 'asdf'))
 
-  many <- letters[1:5]
-  expect_snapshot_failure(expect_match(many, 'asdf'))
+  many <- c("a", "a", "b")
+  expect_snapshot_failure(expect_match(many, "a"))
+  expect_snapshot_failure(expect_match(many, "c", all = FALSE))
 })
 
 test_that("expect_match validates its inputs", {