--
-- Regular expression tests
--
-- Don't want to have to double backslashes in regexes
set standard_conforming_strings = on;
-- Test simple quantified backrefs
select 'bbbbb' ~ '^([bc])\1*$' as t;
 t 
---
 t
(1 row)

select 'ccc' ~ '^([bc])\1*$' as t;
 t 
---
 t
(1 row)

select 'xxx' ~ '^([bc])\1*$' as f;
 f 
---
 f
(1 row)

select 'bbc' ~ '^([bc])\1*$' as f;
 f 
---
 f
(1 row)

select 'b' ~ '^([bc])\1*$' as t;
 t 
---
 t
(1 row)

-- Test quantified backref within a larger expression
select 'abc abc abc' ~ '^(\w+)( \1)+$' as t;
 t 
---
 t
(1 row)

select 'abc abd abc' ~ '^(\w+)( \1)+$' as f;
 f 
---
 f
(1 row)

select 'abc abc abd' ~ '^(\w+)( \1)+$' as f;
 f 
---
 f
(1 row)

select 'abc abc abc' ~ '^(.+)( \1)+$' as t;
 t 
---
 t
(1 row)

select 'abc abd abc' ~ '^(.+)( \1)+$' as f;
 f 
---
 f
(1 row)

select 'abc abc abd' ~ '^(.+)( \1)+$' as f;
 f 
---
 f
(1 row)

-- Test some cases that crashed in 9.2beta1 due to pmatch[] array overrun
select substring('asd TO foo' from ' TO (([a-z0-9._]+|"([^"]+|"")+")+)');
 substring 
-----------
 foo
(1 row)

select substring('a' from '((a))+');
 substring 
-----------
 a
(1 row)

select substring('a' from '((a)+)');
 substring 
-----------
 a
(1 row)

-- Test regexp_match()
select regexp_match('abc', '');
 regexp_match 
--------------
 {""}
(1 row)

select regexp_match('abc', 'bc');
 regexp_match 
--------------
 {bc}
(1 row)

select regexp_match('abc', 'd') is null;
 ?column? 
----------
 t
(1 row)

select regexp_match('abc', '(B)(c)', 'i');
 regexp_match 
--------------
 {b,c}
(1 row)

select regexp_match('abc', 'Bd', 'ig'); -- error
ERROR:  regexp_match() does not support the "global" option
HINT:  Use the regexp_matches function instead.
-- Test lookahead constraints
select regexp_matches('ab', 'a(?=b)b*');
 regexp_matches 
----------------
 {ab}
(1 row)

select regexp_matches('a', 'a(?=b)b*');
 regexp_matches 
----------------
(0 rows)

select regexp_matches('abc', 'a(?=b)b*(?=c)c*');
 regexp_matches 
----------------
 {abc}
(1 row)

select regexp_matches('ab', 'a(?=b)b*(?=c)c*');
 regexp_matches 
----------------
(0 rows)

select regexp_matches('ab', 'a(?!b)b*');
 regexp_matches 
----------------
(0 rows)

select regexp_matches('a', 'a(?!b)b*');
 regexp_matches 
----------------
 {a}
(1 row)

select regexp_matches('b', '(?=b)b');
 regexp_matches 
----------------
 {b}
(1 row)

select regexp_matches('a', '(?=b)b');
 regexp_matches 
----------------
(0 rows)

-- Test lookbehind constraints
select regexp_matches('abb', '(?<=a)b*');
 regexp_matches 
----------------
 {bb}
(1 row)

select regexp_matches('a', 'a(?<=a)b*');
 regexp_matches 
----------------
 {a}
(1 row)

select regexp_matches('abc', 'a(?<=a)b*(?<=b)c*');
 regexp_matches 
----------------
 {abc}
(1 row)

select regexp_matches('ab', 'a(?<=a)b*(?<=b)c*');
 regexp_matches 
----------------
 {ab}
(1 row)

select regexp_matches('ab', 'a*(?<!a)b*');
 regexp_matches 
----------------
 {""}
(1 row)

select regexp_matches('ab', 'a*(?<!a)b+');
 regexp_matches 
----------------
(0 rows)

select regexp_matches('b', 'a*(?<!a)b+');
 regexp_matches 
----------------
 {b}
(1 row)

select regexp_matches('a', 'a(?<!a)b*');
 regexp_matches 
----------------
(0 rows)

select regexp_matches('b', '(?<=b)b');
 regexp_matches 
----------------
(0 rows)

select regexp_matches('foobar', '(?<=f)b+');
 regexp_matches 
----------------
(0 rows)

select regexp_matches('foobar', '(?<=foo)b+');
 regexp_matches 
----------------
 {b}
(1 row)

select regexp_matches('foobar', '(?<=oo)b+');
 regexp_matches 
----------------
 {b}
(1 row)

-- Test optimization of single-chr-or-bracket-expression lookaround constraints
select 'xz' ~ 'x(?=[xy])';
 ?column? 
----------
 f
(1 row)

select 'xy' ~ 'x(?=[xy])';
 ?column? 
----------
 t
(1 row)

select 'xz' ~ 'x(?![xy])';
 ?column? 
----------
 t
(1 row)

select 'xy' ~ 'x(?![xy])';
 ?column? 
----------
 f
(1 row)

select 'x'  ~ 'x(?![xy])';
 ?column? 
----------
 t
(1 row)

select 'xyy' ~ '(?<=[xy])yy+';
 ?column? 
----------
 t
(1 row)

select 'zyy' ~ '(?<=[xy])yy+';
 ?column? 
----------
 f
(1 row)

select 'xyy' ~ '(?<![xy])yy+';
 ?column? 
----------
 f
(1 row)

select 'zyy' ~ '(?<![xy])yy+';
 ?column? 
----------
 t
(1 row)

-- Test conversion of regex patterns to indexable conditions
explain (costs off) select * from pg_proc where proname ~ 'abc';
            QUERY PLAN             
-----------------------------------
 Seq Scan on pg_proc
   Filter: (proname ~ 'abc'::text)
(2 rows)

explain (costs off) select * from pg_proc where proname ~ '^abc';
                              QUERY PLAN                              
----------------------------------------------------------------------
 Index Scan using pg_proc_proname_args_nsp_index on pg_proc
   Index Cond: ((proname >= 'abc'::text) AND (proname < 'abd'::text))
   Filter: (proname ~ '^abc'::text)
(3 rows)

explain (costs off) select * from pg_proc where proname ~ '^abc$';
                         QUERY PLAN                         
------------------------------------------------------------
 Index Scan using pg_proc_proname_args_nsp_index on pg_proc
   Index Cond: (proname = 'abc'::text)
   Filter: (proname ~ '^abc$'::text)
(3 rows)

explain (costs off) select * from pg_proc where proname ~ '^abcd*e';
                              QUERY PLAN                              
----------------------------------------------------------------------
 Index Scan using pg_proc_proname_args_nsp_index on pg_proc
   Index Cond: ((proname >= 'abc'::text) AND (proname < 'abd'::text))
   Filter: (proname ~ '^abcd*e'::text)
(3 rows)

explain (costs off) select * from pg_proc where proname ~ '^abc+d';
                              QUERY PLAN                              
----------------------------------------------------------------------
 Index Scan using pg_proc_proname_args_nsp_index on pg_proc
   Index Cond: ((proname >= 'abc'::text) AND (proname < 'abd'::text))
   Filter: (proname ~ '^abc+d'::text)
(3 rows)

explain (costs off) select * from pg_proc where proname ~ '^(abc)(def)';
                                 QUERY PLAN                                 
----------------------------------------------------------------------------
 Index Scan using pg_proc_proname_args_nsp_index on pg_proc
   Index Cond: ((proname >= 'abcdef'::text) AND (proname < 'abcdeg'::text))
   Filter: (proname ~ '^(abc)(def)'::text)
(3 rows)

explain (costs off) select * from pg_proc where proname ~ '^(abc)$';
                         QUERY PLAN                         
------------------------------------------------------------
 Index Scan using pg_proc_proname_args_nsp_index on pg_proc
   Index Cond: (proname = 'abc'::text)
   Filter: (proname ~ '^(abc)$'::text)
(3 rows)

explain (costs off) select * from pg_proc where proname ~ '^(abc)?d';
               QUERY PLAN               
----------------------------------------
 Seq Scan on pg_proc
   Filter: (proname ~ '^(abc)?d'::text)
(2 rows)

explain (costs off) select * from pg_proc where proname ~ '^abcd(x|(?=\w\w)q)';
                               QUERY PLAN                               
------------------------------------------------------------------------
 Index Scan using pg_proc_proname_args_nsp_index on pg_proc
   Index Cond: ((proname >= 'abcd'::text) AND (proname < 'abce'::text))
   Filter: (proname ~ '^abcd(x|(?=\w\w)q)'::text)
(3 rows)

-- Test for infinite loop in pullback() (CVE-2007-4772)
select 'a' ~ '($|^)*';
 ?column? 
----------
 t
(1 row)

-- These cases expose a bug in the original fix for CVE-2007-4772
select 'a' ~ '(^)+^';
 ?column? 
----------
 t
(1 row)

select 'a' ~ '$($$)+';
 ?column? 
----------
 t
(1 row)

-- More cases of infinite loop in pullback(), not fixed by CVE-2007-4772 fix
select 'a' ~ '($^)+';
 ?column? 
----------
 f
(1 row)

select 'a' ~ '(^$)*';
 ?column? 
----------
 t
(1 row)

select 'aa bb cc' ~ '(^(?!aa))+';
 ?column? 
----------
 f
(1 row)

select 'aa x' ~ '(^(?!aa)(?!bb)(?!cc))+';
 ?column? 
----------
 f
(1 row)

select 'bb x' ~ '(^(?!aa)(?!bb)(?!cc))+';
 ?column? 
----------
 f
(1 row)

select 'cc x' ~ '(^(?!aa)(?!bb)(?!cc))+';
 ?column? 
----------
 f
(1 row)

select 'dd x' ~ '(^(?!aa)(?!bb)(?!cc))+';
 ?column? 
----------
 t
(1 row)

-- Test for infinite loop in fixempties() (Tcl bugs 3604074, 3606683)
select 'a' ~ '((((((a)*)*)*)*)*)*';
 ?column? 
----------
 t
(1 row)

select 'a' ~ '((((((a+|)+|)+|)+|)+|)+|)';
 ?column? 
----------
 t
(1 row)

-- These cases used to give too-many-states failures
select 'x' ~ 'abcd(\m)+xyz';
 ?column? 
----------
 f
(1 row)

select 'a' ~ '^abcd*(((((^(a c(e?d)a+|)+|)+|)+|)+|a)+|)';
 ?column? 
----------
 f
(1 row)

select 'x' ~ 'a^(^)bcd*xy(((((($a+|)+|)+|)+$|)+|)+|)^$';
 ?column? 
----------
 f
(1 row)

select 'x' ~ 'xyz(\Y\Y)+';
 ?column? 
----------
 f
(1 row)

select 'x' ~ 'x|(?:\M)+';
 ?column? 
----------
 t
(1 row)

-- This generates O(N) states but O(N^2) arcs, so it causes problems
-- if arc count is not constrained
select 'x' ~ repeat('x*y*z*', 1000);
ERROR:  invalid regular expression: regular expression is too complex
-- Test backref in combination with non-greedy quantifier
-- https://core.tcl.tk/tcl/tktview/6585b21ca8fa6f3678d442b97241fdd43dba2ec0
select 'Programmer' ~ '(\w).*?\1' as t;
 t 
---
 t
(1 row)

select regexp_matches('Programmer', '(\w)(.*?\1)', 'g');
 regexp_matches 
----------------
 {r,ogr}
 {m,m}
(2 rows)

-- Test for proper matching of non-greedy iteration (bug #11478)
select regexp_matches('foo/bar/baz',
                      '^([^/]+?)(?:/([^/]+?))(?:/([^/]+?))?$', '');
 regexp_matches 
----------------
 {foo,bar,baz}
(1 row)

-- Test that greediness can be overridden by outer quantifier
select regexp_matches('llmmmfff', '^(l*)(.*)(f*)$');
 regexp_matches 
----------------
 {ll,mmmfff,""}
(1 row)

select regexp_matches('llmmmfff', '^(l*){1,1}(.*)(f*)$');
 regexp_matches 
----------------
 {ll,mmmfff,""}
(1 row)

select regexp_matches('llmmmfff', '^(l*){1,1}?(.*)(f*)$');
  regexp_matches  
------------------
 {"",llmmmfff,""}
(1 row)

select regexp_matches('llmmmfff', '^(l*){1,1}?(.*){1,1}?(f*)$');
 regexp_matches 
----------------
 {"",llmmm,fff}
(1 row)

select regexp_matches('llmmmfff', '^(l*?)(.*)(f*)$');
  regexp_matches  
------------------
 {"",llmmmfff,""}
(1 row)

select regexp_matches('llmmmfff', '^(l*?){1,1}(.*)(f*)$');
 regexp_matches 
----------------
 {ll,mmmfff,""}
(1 row)

select regexp_matches('llmmmfff', '^(l*?){1,1}?(.*)(f*)$');
  regexp_matches  
------------------
 {"",llmmmfff,""}
(1 row)

select regexp_matches('llmmmfff', '^(l*?){1,1}?(.*){1,1}?(f*)$');
 regexp_matches 
----------------
 {"",llmmm,fff}
(1 row)

-- Test for infinite loop in cfindloop with zero-length possible match
-- but no actual match (can only happen in the presence of backrefs)
select 'a' ~ '$()|^\1';
 ?column? 
----------
 f
(1 row)

select 'a' ~ '.. ()|\1';
 ?column? 
----------
 f
(1 row)

select 'a' ~ '()*\1';
 ?column? 
----------
 t
(1 row)

select 'a' ~ '()+\1';
 ?column? 
----------
 t
(1 row)

-- Test incorrect removal of capture groups within {0}
select 'xxx' ~ '(.){0}(\1)' as f;
 f 
---
 f
(1 row)

select 'xxx' ~ '((.)){0}(\2)' as f;
 f 
---
 f
(1 row)

select 'xyz' ~ '((.)){0}(\2){0}' as t;
 t 
---
 t
(1 row)

-- Test ancient oversight in when to apply zaptreesubs
select 'abcdef' ~ '^(.)\1|\1.' as f;
 f 
---
 f
(1 row)

select 'abadef' ~ '^((.)\2|..)\2' as f;
 f 
---
 f
(1 row)

-- Add coverage for some cases in checkmatchall
select regexp_match('xy', '.|...');
 regexp_match 
--------------
 {x}
(1 row)

select regexp_match('xyz', '.|...');
 regexp_match 
--------------
 {xyz}
(1 row)

select regexp_match('xy', '.*');
 regexp_match 
--------------
 {xy}
(1 row)

select regexp_match('fooba', '(?:..)*');
 regexp_match 
--------------
 {foob}
(1 row)

select regexp_match('xyz', repeat('.', 260));
 regexp_match 
--------------
 
(1 row)

select regexp_match('foo', '(?:.|){99}');
 regexp_match 
--------------
 {foo}
(1 row)

-- Error conditions
select 'xyz' ~ 'x(\w)(?=\1)';  -- no backrefs in LACONs
ERROR:  invalid regular expression: invalid backreference number
select 'xyz' ~ 'x(\w)(?=(\1))';
ERROR:  invalid regular expression: invalid backreference number
select 'a' ~ '\x7fffffff';  -- invalid chr code
ERROR:  invalid regular expression: invalid escape \ sequence