semver_satisfies 'tilde' corner cases

[weber-martin]

Per https://docs.npmjs.com/misc/semver#tilde-ranges-123-12-1
~1.2.3 := >=1.2.3 <1.(2+1).0 := >=1.2.3 <1.3.0

Note that 1.2.3-alpha < 1.2.3, i.e. "!(>= 1.2.3), but semver_satisfies(1.2.3, 1.2.3-alpha, ~) == 1
Note that 1.3.0-alpha < 1.3.0, but semver_satisfies(1.2.3, 1.3.0-alpha, ~) == 0.

#include <assert.h>
#include <stdio.h>
#include "semver.h"

int satisfies(const char *sv1, const char *sv2, const char *op) {
	semver_t v1, v2;
	int rc;

	rc = semver_parse(sv1, &v1);
	assert(!rc);
	rc = semver_parse(sv2, &v2);
	assert(!rc);
	rc = semver_satisfies(v1, v2, op);
	semver_free(&v1);
	semver_free(&v2);
	return rc;
}

int main(int argc, char *argv[]) {
	struct bundle {
		const char *sv1;
		const char *sv2;
	} cases [] = {
		{"1.2.3", "1.2.3"},
		{"1.2.3", "1.2.3-alpha"}, /* 1.2.3 > 1.2.3-alpha ! */
		{"1.2.3", "2.0.0"},
		{"1.2.3", "2.0.0-alpha"}, /* 2.0.0-alpha < 2.0.0 ! */
	};
	size_t num_cases = sizeof(cases) / sizeof(struct bundle), i;

	for (i=0; i < num_cases; ++i)
		printf("%s ^ %s = %d\n", cases[i].sv1, cases[i].sv2, 
			satisfies(cases[i].sv1, cases[i].sv2, "~"));
	return 0;
}

outputs

1.2.3 ^ 1.2.3 = 1
1.2.3 ^ 1.2.3-alpha = 1 # should be 0
1.2.3 ^ 2.0.0 = 0
1.2.3 ^ 2.0.0-alpha = 0 # should be 1