sqlite/test/atof1.test

# 2012 June 18
#
# 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.
#
#***********************************************************************
# 
# Tests of the sqlite3AtoF() function.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

expr srand(1)
for {set i 1} {$i<10000} {incr i} {
  set pow [expr {int((rand()-0.5)*100)}]
  set x [expr {pow((rand()-0.5)*2*rand(),$pow)}]
  set xf [format %.32e $x]

  # Verify that text->real conversions get exactly same ieee754 floating-
  # point value in SQLite as they do in TCL.
  #
  do_test 1.$i.1 {
    set y [db eval "SELECT $xf=\$x"]
    if {!$y} {
      puts -nonewline \173[db eval "SELECT real2hex($xf), real2hex(\$x)"]\175
      db eval "SELECT $xf+0.0 AS a, \$x AS b" {
        puts [format "\n%.60e\n%.60e\n%.60e" $x $a $b]
      }
    }
    set y
  } {1}

  # FIX ME.  The following tests (real->text->real round-trips) sometimes
  # fail for large floating-point values.  Skip them for now...
  #
  if {abs($x)>1e50} continue

  # Verify that round-trip real->text->real conversions using the quote()
  # function preserve the bits of the numeric value exactly.
  #
  do_test 1.$i.2 {
    set y [db eval {SELECT $x=CAST(quote($x) AS real)}]
    if {!$y} {
      db eval {SELECT real2hex($x) a, real2hex(CAST(quote($x) AS real)) b} {}
      puts "\nIN:    $a $xf"
      puts [format {QUOTE: %16s %s} {} [db eval {SELECT quote($x)}]]
      db eval {SELECT CAST(quote($x) AS real) c} {}
      puts "OUT:   $b [format %.32e $c]"
    }
    set y
  } {1}
}


finish_test