From 6f85a068aa1cfa8f8a4e3616d56e422aa6d74d11 Mon Sep 17 00:00:00 2001
From: edward-burn <9583964+edward-burn@users.noreply.github.com>
Date: Thu, 15 Aug 2024 14:00:30 -0700
Subject: [PATCH] define [[.stringr_pattern (#569)

Fixes #529
---
 NAMESPACE                       | 1 +
 NEWS.md                         | 3 +++
 R/modifiers.R                   | 9 +++++++++
 tests/testthat/test-modifiers.R | 7 +++++++
 4 files changed, 20 insertions(+)

diff --git a/NAMESPACE b/NAMESPACE
index 07f842ab..3f1bffc3 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -2,6 +2,7 @@
 
 S3method("[",stringr_pattern)
 S3method("[",stringr_view)
+S3method("[[",stringr_pattern)
 S3method(print,stringr_view)
 S3method(type,character)
 S3method(type,default)
diff --git a/NEWS.md b/NEWS.md
index 365fd68b..ff177e75 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,8 @@
 # stringr (development version)
 
+* Adds `[[.stringr_pattern` method to go along with existing `[.stringr_pattern` 
+  method (@edward-burn, #569).
+
 * In `str_replace_all()`, a `replacement` function now receives all values in
   a single vector. This radically improves performance at the cost of breaking
   some existing uses (#462).
diff --git a/R/modifiers.R b/R/modifiers.R
index d183ac0b..7783b807 100644
--- a/R/modifiers.R
+++ b/R/modifiers.R
@@ -227,6 +227,15 @@ type.default <- function(x, error_call = caller_env()) {
   )
 }
 
+#' @export
+`[[.stringr_pattern` <- function(x, i) {
+  structure(
+    NextMethod(),
+    options = attr(x, "options"),
+    class = class(x)
+  )
+}
+
 as_bare_character <- function(x, call = caller_env()) {
   if (is.character(x) && !is.object(x)) {
     # All OK!
diff --git a/tests/testthat/test-modifiers.R b/tests/testthat/test-modifiers.R
index 34495494..aa1624c8 100644
--- a/tests/testthat/test-modifiers.R
+++ b/tests/testthat/test-modifiers.R
@@ -36,3 +36,10 @@ test_that("subsetting preserves class and options", {
   x <- regex("a", multiline = TRUE)
   expect_equal(x[], x)
 })
+
+test_that("stringr_pattern methods", {
+  ex <- coll(c("foo", "bar"))
+  expect_true(inherits(ex[1], "stringr_pattern"))
+  expect_true(inherits(ex[[1]], "stringr_pattern"))
+
+})