From 0b93961053439db7ebc175ee456ba9a7694f4811 Mon Sep 17 00:00:00 2001
From: Andrew Lamb <andrew@nerdnetworks.org>
Date: Wed, 8 Apr 2026 17:02:32 -0400
Subject: [PATCH 1/2] Add more regexp_replace test coverage

---
 .../test_files/regexp/regexp_replace.slt      | 141 +++++++++++++++---
 1 file changed, 124 insertions(+), 17 deletions(-)

diff --git a/datafusion/sqllogictest/test_files/regexp/regexp_replace.slt b/datafusion/sqllogictest/test_files/regexp/regexp_replace.slt
index a2eccfce5f69..087ad379a2eb 100644
--- a/datafusion/sqllogictest/test_files/regexp/regexp_replace.slt
+++ b/datafusion/sqllogictest/test_files/regexp/regexp_replace.slt
@@ -128,29 +128,136 @@ from (values ('a'), ('b')) as tbl(col);
 NULL NULL NULL
 NULL NULL NULL
 
+# Fixture for testing optimizations in regexp_replace
+statement ok
+CREATE TABLE regexp_replace_optimized_cases (
+    value string,
+    regexp string,
+    replacement string,
+    expected string
+);
+
+# Extract domain from URL using anchored pattern with trailing .*
+# This tests that the full URL suffix is replaced, not just the matched prefix.
+statement ok
+INSERT INTO regexp_replace_optimized_cases VALUES
+    ('https://www.example.com/path/to/page?q=1', '^https?://(?:www\.)?([^/]+)/.*$', '\1', 'example.com'),
+    ('http://test.org/foo/bar', '^https?://(?:www\.)?([^/]+)/.*$', '\1', 'test.org'),
+    ('https://example.com/', '^https?://(?:www\.)?([^/]+)/.*$', '\1', 'example.com'),
+    ('not-a-url', '^https?://(?:www\.)?([^/]+)/.*$', '\1', 'not-a-url');
+
+# More than one capture group should disable the short-regex fast path.
+# This still uses replacement \1, but captures_len() will be > 2, so the
+# implementation must fall back to the normal regexp_replace path.
+statement ok
+INSERT INTO regexp_replace_optimized_cases VALUES
+    ('https://www.example.com/path/to/page?q=1', '^https?://((www\.)?([^/]+))/.*$', '\1', 'www.example.com'),
+    ('http://test.org/foo/bar', '^https?://((www\.)?([^/]+))/.*$', '\1', 'test.org'),
+    ('not-a-url', '^https?://((www\.)?([^/]+))/.*$', '\1', 'not-a-url');
+
 # If the overall pattern matches but capture group 1 does not participate,
 # regexp_replace(..., '\1') should substitute the empty string, not keep
 # the original input.
-query B
-SELECT regexp_replace('bzzz', '^(a)?b.*$', '\1') = '';
-----
-true
+statement ok
+INSERT INTO regexp_replace_optimized_cases VALUES
+    ('bzzz', '^(a)?b.*$', '\1', '');
 
 # Stripping trailing .*$ must not change match semantics for inputs with
 # newlines when the original pattern does not use the 's' flag.
-query B
-SELECT regexp_replace(concat('http://x/', chr(10), 'rest'), '^https?://([^/]+)/.*$', '\1')
-       = concat('http://x/', chr(10), 'rest');
-----
-true
+statement ok
+INSERT INTO regexp_replace_optimized_cases VALUES
+    (concat('http://x/', chr(10), 'rest'), '^https?://([^/]+)/.*$', '\1', concat('http://x/', chr(10), 'rest'));
 
 # Inline multiline mode still allows only the matched prefix to be replaced.
 # The remainder of the string must be preserved.
-query B
-SELECT regexp_replace(
-           concat('http://x/path', chr(10), 'rest'),
-           '^(?m)https?://([^/]+)/.*$',
-           '\1'
-       ) = concat('x', chr(10), 'rest');
-----
-true
+statement ok
+INSERT INTO regexp_replace_optimized_cases VALUES
+    (concat('http://x/path', chr(10), 'rest'), '^(?m)https?://([^/]+)/.*$', '\1', concat('x', chr(10), 'rest'));
+
+query TB
+SELECT value, regexp_replace(value, regexp, replacement) = expected
+FROM regexp_replace_optimized_cases
+ORDER BY regexp, value, replacement, expected;
+----
+http://x/path
+rest true
+bzzz true
+http://test.org/foo/bar true
+https://www.example.com/path/to/page?q=1 true
+not-a-url true
+http://test.org/foo/bar true
+https://example.com/ true
+https://www.example.com/path/to/page?q=1 true
+not-a-url true
+http://x/
+rest true
+
+query TB
+SELECT value, regexp_replace(
+           arrow_cast(value, 'LargeUtf8'),
+           arrow_cast(regexp, 'LargeUtf8'),
+           arrow_cast(replacement, 'LargeUtf8')
+       ) = arrow_cast(expected, 'LargeUtf8')
+FROM regexp_replace_optimized_cases
+ORDER BY regexp, value, replacement, expected;
+----
+http://x/path
+rest true
+bzzz true
+http://test.org/foo/bar true
+https://www.example.com/path/to/page?q=1 true
+not-a-url true
+http://test.org/foo/bar true
+https://example.com/ true
+https://www.example.com/path/to/page?q=1 true
+not-a-url true
+http://x/
+rest true
+
+query TB
+SELECT value, regexp_replace(
+           arrow_cast(value, 'Utf8View'),
+           arrow_cast(regexp, 'Utf8View'),
+           arrow_cast(replacement, 'Utf8View')
+       ) = arrow_cast(expected, 'Utf8View')
+FROM regexp_replace_optimized_cases
+ORDER BY regexp, value, replacement, expected;
+----
+http://x/path
+rest true
+bzzz true
+http://test.org/foo/bar true
+https://www.example.com/path/to/page?q=1 true
+not-a-url true
+http://test.org/foo/bar true
+https://example.com/ true
+https://www.example.com/path/to/page?q=1 true
+not-a-url true
+http://x/
+rest true
+
+query TB
+SELECT value, regexp_replace(
+           arrow_cast(value, 'Dictionary(Int32, Utf8)'),
+           arrow_cast(regexp, 'Dictionary(Int32, Utf8)'),
+           arrow_cast(replacement, 'Dictionary(Int32, Utf8)')
+       ) = arrow_cast(expected, 'Dictionary(Int32, Utf8)')
+FROM regexp_replace_optimized_cases
+ORDER BY regexp, value, replacement, expected;
+----
+http://x/path
+rest true
+bzzz true
+http://test.org/foo/bar true
+https://www.example.com/path/to/page?q=1 true
+not-a-url true
+http://test.org/foo/bar true
+https://example.com/ true
+https://www.example.com/path/to/page?q=1 true
+not-a-url true
+http://x/
+rest true
+
+# cleanup
+statement ok
+DROP TABLE regexp_replace_optimized_cases;

From d2b8b01099a162042624424526121dc8db3d5a71 Mon Sep 17 00:00:00 2001
From: Andrew Lamb <andrew@nerdnetworks.org>
Date: Thu, 9 Apr 2026 07:12:45 -0400
Subject: [PATCH 2/2] Keep multi-line tests in own fixture

---
 .../test_files/regexp/regexp_replace.slt      | 48 ++++++++-----------
 1 file changed, 21 insertions(+), 27 deletions(-)

diff --git a/datafusion/sqllogictest/test_files/regexp/regexp_replace.slt b/datafusion/sqllogictest/test_files/regexp/regexp_replace.slt
index 087ad379a2eb..e3200e334cdf 100644
--- a/datafusion/sqllogictest/test_files/regexp/regexp_replace.slt
+++ b/datafusion/sqllogictest/test_files/regexp/regexp_replace.slt
@@ -128,6 +128,27 @@ from (values ('a'), ('b')) as tbl(col);
 NULL NULL NULL
 NULL NULL NULL
 
+
+# Stripping trailing .*$ must not change match semantics for inputs with
+# newlines when the original pattern does not use the 's' flag.
+query B
+SELECT regexp_replace(concat('http://x/', chr(10), 'rest'), '^https?://([^/]+)/.*$', '\1')
+       = concat('http://x/', chr(10), 'rest');
+----
+true
+
+# Inline multiline mode still allows only the matched prefix to be replaced.
+# The remainder of the string must be preserved.
+query B
+SELECT regexp_replace(
+           concat('http://x/path', chr(10), 'rest'),
+           '^(?m)https?://([^/]+)/.*$',
+           '\1'
+       ) = concat('x', chr(10), 'rest');
+----
+true
+
+
 # Fixture for testing optimizations in regexp_replace
 statement ok
 CREATE TABLE regexp_replace_optimized_cases (
@@ -162,25 +183,12 @@ statement ok
 INSERT INTO regexp_replace_optimized_cases VALUES
     ('bzzz', '^(a)?b.*$', '\1', '');
 
-# Stripping trailing .*$ must not change match semantics for inputs with
-# newlines when the original pattern does not use the 's' flag.
-statement ok
-INSERT INTO regexp_replace_optimized_cases VALUES
-    (concat('http://x/', chr(10), 'rest'), '^https?://([^/]+)/.*$', '\1', concat('http://x/', chr(10), 'rest'));
-
-# Inline multiline mode still allows only the matched prefix to be replaced.
-# The remainder of the string must be preserved.
-statement ok
-INSERT INTO regexp_replace_optimized_cases VALUES
-    (concat('http://x/path', chr(10), 'rest'), '^(?m)https?://([^/]+)/.*$', '\1', concat('x', chr(10), 'rest'));
 
 query TB
 SELECT value, regexp_replace(value, regexp, replacement) = expected
 FROM regexp_replace_optimized_cases
 ORDER BY regexp, value, replacement, expected;
 ----
-http://x/path
-rest true
 bzzz true
 http://test.org/foo/bar true
 https://www.example.com/path/to/page?q=1 true
@@ -189,8 +197,6 @@ http://test.org/foo/bar true
 https://example.com/ true
 https://www.example.com/path/to/page?q=1 true
 not-a-url true
-http://x/
-rest true
 
 query TB
 SELECT value, regexp_replace(
@@ -201,8 +207,6 @@ SELECT value, regexp_replace(
 FROM regexp_replace_optimized_cases
 ORDER BY regexp, value, replacement, expected;
 ----
-http://x/path
-rest true
 bzzz true
 http://test.org/foo/bar true
 https://www.example.com/path/to/page?q=1 true
@@ -211,8 +215,6 @@ http://test.org/foo/bar true
 https://example.com/ true
 https://www.example.com/path/to/page?q=1 true
 not-a-url true
-http://x/
-rest true
 
 query TB
 SELECT value, regexp_replace(
@@ -223,8 +225,6 @@ SELECT value, regexp_replace(
 FROM regexp_replace_optimized_cases
 ORDER BY regexp, value, replacement, expected;
 ----
-http://x/path
-rest true
 bzzz true
 http://test.org/foo/bar true
 https://www.example.com/path/to/page?q=1 true
@@ -233,8 +233,6 @@ http://test.org/foo/bar true
 https://example.com/ true
 https://www.example.com/path/to/page?q=1 true
 not-a-url true
-http://x/
-rest true
 
 query TB
 SELECT value, regexp_replace(
@@ -245,8 +243,6 @@ SELECT value, regexp_replace(
 FROM regexp_replace_optimized_cases
 ORDER BY regexp, value, replacement, expected;
 ----
-http://x/path
-rest true
 bzzz true
 http://test.org/foo/bar true
 https://www.example.com/path/to/page?q=1 true
@@ -255,8 +251,6 @@ http://test.org/foo/bar true
 https://example.com/ true
 https://www.example.com/path/to/page?q=1 true
 not-a-url true
-http://x/
-rest true
 
 # cleanup
 statement ok