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#include <inttypes.h>
#include <string.h>
#include <stdio.h>
#include "grisu3_parse.h"
#include "grisu3_print.h"
#define TEST(x, s) do { \
if (!(x)) { \
fprintf(stderr, \
"fail: %s\n" \
" input: %s\n" \
" expected: %.17g\n" \
" got: %.17g\n" \
" binary xor: 0x%016"PRId64"\n", \
s, buf, expect, v, (a ^ b)); \
return 1; \
} \
} while (0)
static int test_parse_double(char *buf)
{
const char *k, *end;
double v, expect;
uint64_t a = 0, b = 0;
int len = strlen(buf);
end = buf + len;
expect = strtod(buf, 0);
/* Include '\0' in bytes being parsed to make strtod safe. */
k = grisu3_parse_double(buf, len, &v);
/* Make sure we parsed and accepted everything. */
TEST(k == end, "didn't parse to end");
a = grisu3_cast_uint64_from_double(expect);
b = grisu3_cast_uint64_from_double(v);
#ifdef GRISU3_PARSE_ALLOW_ERROR
/*
* Just where exponent wraps, this assumption will be incorrect.
* TODO: need next higher double function.
*/
TEST(a - b <= 1, "binary representation differs by more than lsb");
#else
/* Binary comparison should match. */
TEST(expect == v, "double representation differs");
TEST(a == b, "binary representation differs");
#endif
#if 0
/* This will print the test data also when correct. */
TEST(0, "test case passed, just debugging");
#endif
return 0;
}
/*
* We currently do not test grisu3_print_double because
* it is a direct port of dtoa_grisu3 from grisu3.c
* which presumably has been tested in MathGeoLib.
*
* grisu3_parse_double is a new implementation.
*/
int test_suite()
{
char buf[50];
int fail = 0;
fail += test_parse_double("1.23434");
fail += test_parse_double("1234.34");
fail += test_parse_double("1234.34e4");
fail += test_parse_double("1234.34e-4");
fail += test_parse_double("1.23434E+4");
fail += test_parse_double("3.2897984798741413E+194");
fail += test_parse_double("-3.2897984798741413E-194");
sprintf(buf, "3289798479874141.314124124128497098e109");
fail += test_parse_double(buf);
sprintf(buf, "3289798479874141.314124124128497098e209");
fail += test_parse_double(buf);
sprintf(buf, "-3289798479874141.314124124128497098e209");
fail += test_parse_double(buf);
sprintf(buf, "3289798479874141.314124124128497098e+209");
fail += test_parse_double(buf);
sprintf(buf, "-3289798479874141.314124124128497098e-209");
fail += test_parse_double(buf);
return fail;
}
void example()
{
double v;
const char *buf = "1234.34e-4";
const char *x, *end;
char result_buf[50];
int len;
fprintf(stderr, "grisu3_parse_double example:\n parsing '%s' as double\n", buf);
/* A non-numeric terminator (e.g. '\0') is required to ensure strtod fallback is safe. */
len = strlen(buf);
end = buf + len;
x = grisu3_parse_double(buf, len, &v);
if (x == 0) {
fprintf(stderr, "syntax or range error\n");
} else if (x == buf) {
fprintf(stderr, "parse double failed\n");
} else if (x != end) {
fprintf(stderr, "parse double did not read everything\n");
} else {
fprintf(stderr, "got: %.17g\n", v);
}
/*
* TODO: with the current example: the input "0.123434" is printed
* as "1.23434e-1" which is sub-optimal and different from sprintf.
*
* This is not the grisu3 algorithm but a post formatting step
* in grisu3_print_double (originally dtoa_grisu) and may be a bug
* in the logic choosing the best print format.
* sprintf "%.17g" and "%g" both print as "0.123434"
*/
fprintf(stderr, "grisu3_print_double example:\n printing %g\n", v);
grisu3_print_double(v, result_buf);
fprintf(stderr, "got: %s\n", result_buf);
}
int main()
{
example();
fprintf(stderr, "running tests\n");
if (test_suite()) {
fprintf(stderr, "GRISU3 PARSE TEST FAILED\n");
return -1;
} else {
fprintf(stderr, "GRISU3 PARSE TEST PASSED\n");
return 0;
}
}
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