SQLite

    if( zCharSet ){
      sqlite3_free(azChar);
    }
  }
  sqlite3_result_text(context, (char*)zIn, nIn, SQLITE_TRANSIENT);
}

/* The core implementation of the CONCAT(...) and CONCAT_WS(SEP,...)
** functions.
**
** Return a string value that is the concatenation of all non-null
** entries in argv[].  Use zSep as the separator.
*/
static void concatFuncCore(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv,
  int nSep,
  const char *zSep
){
  i64 j, k, n = 0;
  int i;
  char *z;
  for(i=0; i<argc; i++){
    n += sqlite3_value_bytes(argv[i]);
  }
  n += (argc-1)*nSep;
  z = sqlite3_malloc64(n+1);
  if( z==0 ){
    sqlite3_result_error_nomem(context);
    return;
  }
  j = 0;
  for(i=0; i<argc; i++){
    k = sqlite3_value_bytes(argv[i]);
    if( k>0 ){
      const char *v = (const char*)sqlite3_value_text(argv[i]);
      if( ALWAYS(v!=0) ){
        if( j>0 && nSep>0 ){
          memcpy(&z[j], zSep, nSep);
          j += nSep;
        }
        memcpy(&z[j], v, k);
        j += k;
      }
    }
  }
  z[j] = 0;
  assert( j<=n );
  sqlite3_result_text64(context, z, n, sqlite3_free, SQLITE_UTF8);
}

/*
** The CONCAT(...) function.  Generate a string result that is the
** concatentation of all non-null arguments.
*/
static void concatFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  concatFuncCore(context, argc, argv, 0, "");
}

/*
** The CONCAT_WS(separator, ...) function.
**
** Generate a string that is the concatenation of 2nd through the Nth
** argument.  Use the first argument (which must be non-NULL) as the
** separator.
*/
static void concatwsFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  int nSep = sqlite3_value_bytes(argv[0]);
  const char *zSep = (const char*)sqlite3_value_text(argv[0]);
  if( zSep==0 ) return;
  concatFuncCore(context, argc-1, argv+1, nSep, zSep);
}


#ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
/*
** The "unknown" function is automatically substituted in place of
** any unrecognized function name when doing an EXPLAIN or EXPLAIN QUERY PLAN
** when the SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION compile-time option is used.
** When the "sqlite3" command-line shell is built using this functionality,

    FUNCTION(round,              2, 0, 0, roundFunc        ),
#endif
    FUNCTION(upper,              1, 0, 0, upperFunc        ),
    FUNCTION(lower,              1, 0, 0, lowerFunc        ),
    FUNCTION(hex,                1, 0, 0, hexFunc          ),
    FUNCTION(unhex,              1, 0, 0, unhexFunc        ),
    FUNCTION(unhex,              2, 0, 0, unhexFunc        ),
    FUNCTION(concat,            -1, 0, 0, concatFunc       ),
    FUNCTION(concat,             0, 0, 0, 0                ),
    FUNCTION(concat_ws,         -1, 0, 0, concatwsFunc     ),
    FUNCTION(concat_ws,          0, 0, 0, 0                ),
    FUNCTION(concat_ws,          1, 0, 0, 0                ),
    INLINE_FUNC(ifnull,          2, INLINEFUNC_coalesce, 0 ),
    VFUNCTION(random,            0, 0, 0, randomFunc       ),
    VFUNCTION(randomblob,        1, 0, 0, randomBlob       ),
    FUNCTION(nullif,             2, 0, 1, nullifFunc       ),
    DFUNCTION(sqlite_version,    0, 0, 0, versionFunc      ),
    DFUNCTION(sqlite_source_id,  0, 0, 0, sourceidFunc     ),
    FUNCTION(sqlite_log,         2, 0, 0, errlogFunc       ),

# 2023-08-29
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#*************************************************************************
#
# Test cases for SQL newer functions
#
set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_execsql_test func9-100 {
  SELECT concat('abc',123,null,'xyz');
} {abc123xyz}
do_execsql_test func9-110 {
  SELECT typeof(concat(null));
} {text}
do_catchsql_test func9-120 {
  SELECT concat();
} {1 {wrong number of arguments to function concat()}}
do_execsql_test func9-130 {
  SELECT concat_ws(',',1,2,3,4,5,6,7,8,NULL,9,10,11,12);
} {1,2,3,4,5,6,7,8,9,10,11,12}
do_execsql_test func9-140 {
  SELECT concat_ws(NULL,1,2,3,4,5,6,7,8,NULL,9,10,11,12);
} {{}}
do_catchsql_test func9-150 {
  SELECT concat_ws();
} {1 {wrong number of arguments to function concat_ws()}}
do_catchsql_test func9-160 {
  SELECT concat_ws(',');
} {1 {wrong number of arguments to function concat_ws()}}


finish_test