diff --git a/fish-rust/src/common.rs b/fish-rust/src/common.rs
index 4c95e9fed..cde809db0 100644
--- a/fish-rust/src/common.rs
+++ b/fish-rust/src/common.rs
@@ -187,3 +187,33 @@ const fn cmp_slice(s1: &[char], s2: &[char]) -> Ordering {
         assert_sorted_by_name!($slice, name);
     };
 }
+mod tests {
+    use crate::{
+        common::{escape_string, EscapeStringStyle},
+        wchar::widestrs,
+    };
+
+    #[widestrs]
+    pub fn test_escape_string() {
+        let regex = |input| escape_string(input, EscapeStringStyle::Regex);
+
+        // plain text should not be needlessly escaped
+        assert_eq!(regex("hello world!"L), "hello world!"L);
+
+        // all the following are intended to be ultimately matched literally - even if they don't look
+        // like that's the intent - so we escape them.
+        assert_eq!(regex(".ext"L), "\\.ext"L);
+        assert_eq!(regex("{word}"L), "\\{word\\}"L);
+        assert_eq!(regex("hola-mundo"L), "hola\\-mundo"L);
+        assert_eq!(
+            regex("$17.42 is your total?"L),
+            "\\$17\\.42 is your total\\?"L
+        );
+        assert_eq!(
+            regex("not really escaped\\?"L),
+            "not really escaped\\\\\\?"L
+        );
+    }
+}
+
+crate::ffi_tests::add_test!("escape_string", tests::test_escape_string);
diff --git a/src/fish_tests.cpp b/src/fish_tests.cpp
index d4217eeb7..81e6f2ebf 100644
--- a/src/fish_tests.cpp
+++ b/src/fish_tests.cpp
@@ -5827,34 +5827,6 @@ static void test_wwrite_to_fd() {
     (void)remove(t);
 }
 
-static void test_pcre2_escape() {
-    say(L"Testing escaping strings as pcre2 literals");
-    // plain text should not be needlessly escaped
-    auto input = L"hello world!";
-    auto escaped = escape_string(input, 0, STRING_STYLE_REGEX);
-    if (escaped != input) {
-        err(L"Input string %ls unnecessarily PCRE2 escaped as %ls", input, escaped.c_str());
-    }
-
-    // all the following are intended to be ultimately matched literally - even if they don't look
-    // like that's the intent - so we escape them.
-    const wchar_t *const tests[][2] = {
-        {L".ext", L"\\.ext"},
-        {L"{word}", L"\\{word\\}"},
-        {L"hola-mundo", L"hola\\-mundo"},
-        {L"$17.42 is your total?", L"\\$17\\.42 is your total\\?"},
-        {L"not really escaped\\?", L"not really escaped\\\\\\?"},
-    };
-
-    for (const auto &test : tests) {
-        auto escaped = escape_string(test[0], 0, STRING_STYLE_REGEX);
-        if (escaped != test[1]) {
-            err(L"pcre2_escape error: pcre2_escape(%ls) -> %ls, expected %ls", test[0],
-                escaped.c_str(), test[1]);
-        }
-    }
-}
-
 maybe_t<int> builtin_string(parser_t &parser, io_streams_t &streams, const wchar_t **argv);
 static void run_one_string_test(const wchar_t *const *argv_raw, int expected_rc,
                                 const wchar_t *expected_out) {
@@ -7092,7 +7064,6 @@ static const test_t s_tests[]{
     {TEST_GROUP("indents"), test_indents},
     {TEST_GROUP("utf8"), test_utf8},
     {TEST_GROUP("escape_sequences"), test_escape_sequences},
-    {TEST_GROUP("pcre2_escape"), test_pcre2_escape},
     {TEST_GROUP("lru"), test_lru},
     {TEST_GROUP("expand"), test_expand},
     {TEST_GROUP("expand"), test_expand_overflow},