SQLite

  pMem->u.r = sqlite3VdbeRealValue(pMem);
  MemSetTypeFlag(pMem, MEM_Real);
  return SQLITE_OK;
}

/* Compare a floating point value to an integer.  Return true if the two
** values are the same within the precision of the floating point value.
**
** This function assumes that i was obtained by assignment from r1.
**
** For some versions of GCC on 32-bit machines, if you do the more obvious
** comparison of "r1==(double)i" you sometimes get an answer of false even
** though the r1 and (double)i values are bit-for-bit the same.
*/
int sqlite3RealSameAsInt(double r1, sqlite3_int64 i){
  double r2 = (double)i;
  return r1==0.0
      || (memcmp(&r1, &r2, sizeof(r1))==0
          && i >= -2251799813685248 && i < 2251799813685248);
}

/*
** Convert pMem so that it has type MEM_Real or MEM_Int.
** Invalidate any prior representations.
**
** Every effort is made to force the conversion, even if the input

do_test cast-1.51 {
  execsql {SELECT CAST('123.5abc' AS numeric)}
} 123.5
do_test cast-1.53 {
  execsql {SELECT CAST('123.5abc' AS integer)}
} 123

do_test cast-1.60 {
  execsql {SELECT CAST(null AS REAL)}
} {{}}
do_test cast-1.61 {
  execsql {SELECT typeof(CAST(null AS REAL))}
} {null}
do_test cast-1.62 {
  execsql {SELECT CAST(1 AS REAL)}
} {1.0}
do_test cast-1.63 {
  execsql {SELECT typeof(CAST(1 AS REAL))}
} {real}
do_test cast-1.64 {
  execsql {SELECT CAST('1' AS REAL)}
} {1.0}
do_test cast-1.65 {
  execsql {SELECT typeof(CAST('1' AS REAL))}
} {real}
do_test cast-1.66 {
  execsql {SELECT CAST('abc' AS REAL)}
} {0.0}
do_test cast-1.67 {
  execsql {SELECT typeof(CAST('abc' AS REAL))}
} {real}
do_test cast-1.68 {
  execsql {SELECT CAST(x'31' AS REAL)}
} {1.0}
do_test cast-1.69 {
  execsql {SELECT typeof(CAST(x'31' AS REAL))}
} {real}


# Ticket #1662.  Ignore leading spaces in numbers when casting.
#
do_test cast-2.1 {

      execsql {
        SELECT CAST(CAST(x'39323233333732303336383534373734383030' AS real)
                    AS integer)
      }
    } 9223372036854774784
  }
}
do_test cast-3.31 {
  execsql {SELECT CAST(NULL AS numeric)}
} {{}}

# Test to see if it is possible to trick SQLite into reading past 
# the end of a blob when converting it to a number.
do_test cast-3.32.1 {
  set blob "1234567890"

} {-9223372036854775808 -9223372036854775808 -9223372036854775808}

# EVIDENCE-OF: R-33990-33527 When casting to INTEGER, if the text looks
# like a floating point value with an exponent, the exponent will be
# ignored because it is no part of the integer prefix.
# EVIDENCE-OF: R-24225-46995 For example, "(CAST '123e+5' AS INTEGER)"
# results in 123, not in 12300000.
do_execsql_test cast-5.3 {
  SELECT CAST('123e+5' AS INTEGER);
  SELECT CAST('123e+5' AS NUMERIC);
  SELECT CAST('123e+5' AS REAL);
} {123 12300000 12300000.0}


# The following does not have anything to do with the CAST operator,
# but it does deal with affinity transformations.
#
do_execsql_test cast-6.1 {
  DROP TABLE IF EXISTS t1;
  CREATE TABLE t1(a NUMERIC);
  INSERT INTO t1 VALUES
     ('9000000000000000001'),
     ('9000000000000000001 '),
     (' 9000000000000000001'),
     (' 9000000000000000001 ');
  SELECT * FROM t1;
} {9000000000000000001 9000000000000000001 9000000000000000001 9000000000000000001}

# 2019-06-07
# https://www.sqlite.org/src/info/4c2d7639f076aa7c
do_execsql_test cast-7.1 {
  SELECT CAST('-' AS NUMERIC);
} {0}
do_execsql_test cast-7.2 {
  SELECT CAST('-0' AS NUMERIC);
} {0}
do_execsql_test cast-7.3 {
  SELECT CAST('+' AS NUMERIC);
} {0}
do_execsql_test cast-7.4 {
  SELECT CAST('/' AS NUMERIC);
} {0}

# 2019-06-07
# https://www.sqlite.org/src/info/e8bedb2a184001bb
do_execsql_test cast-7.10 {
  SELECT '' - 2851427734582196970;
} {-2851427734582196970}
do_execsql_test cast-7.11 {
  SELECT 0 - 2851427734582196970;
} {-2851427734582196970}
do_execsql_test cast-7.12 {
  SELECT '' - 1;
} {-1}

# 2019-06-10
# https://www.sqlite.org/src/info/dd6bffbfb6e61db9
#
# EVIDENCE-OF: R-09295-61337 Casting a TEXT or BLOB value into NUMERIC

} 0
do_execsql_test cast-7.32 {
  SELECT CAST('.' AS numeric);
} 0
do_execsql_test cast-7.33 {
  SELECT -CAST('.' AS numeric);
} 0

# 2019-06-12
# https://www.sqlite.org/src/info/674385aeba91c774
#
do_execsql_test cast-7.40 {
  SELECT CAST('-0.0' AS numeric);
} 0
do_execsql_test cast-7.41 {
  SELECT CAST('0.0' AS numeric);
} 0
do_execsql_test cast-7.42 {
  SELECT CAST('+0.0' AS numeric);
} 0
do_execsql_test cast-7.43 {
  SELECT CAST('-1.0' AS numeric);
} -1



finish_test