marko/semver
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Reduce code complexity by moving to data-driven algorithms.

Browse Source
This commit is contained in:
Marko Zivanovic
2015-10-09 23:30:19 +02:00
parent 59d46ce4f8
commit b6ea8dcc52
2 changed files with 62 additions and 30 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/Semver200_comparator.cpp
+46 -22
View File
@@ -23,6 +23,8 @@ SOFTWARE.
*/
#include <algorithm>
#include <functional>
#include <map>
#include "version.h"
using namespace std;
@@ -31,6 +33,7 @@ namespace {
using namespace version;
// Compare normal version identifiers.
int compare_normal(const Version_data& l, const Version_data& r) {
if (l.major > r.major) return 1;
if (l.major < r.major) return -1;
@@ -41,46 +44,67 @@ namespace {
return 0;
}
int compare_prerel_identifiers(const Prerelease_identifier& l, const Prerelease_identifier& r) {
if (l.second == Identifier_type::alnum && r.second == Identifier_type::alnum) {
auto cmp = l.first.compare(r.first);
if (cmp == 0) return cmp;
// Compare alphanumeric prerelease identifiers.
inline int cmp_alnum_prerel_ids(const string& l, const string& r) {
auto cmp = l.compare(r);
if (cmp == 0) {
return cmp;
} else {
return cmp > 0 ? 1 : -1;
} else if (l.second == Identifier_type::alnum && r.second == Identifier_type::num) {
return 1;
} else if (l.second == Identifier_type::num && r.second == Identifier_type::alnum) {
return -1;
} else if (l.second == Identifier_type::num && r.second == Identifier_type::num) {
int li = stoi(l.first);
int ri = stoi(r.first);
if (li == ri) return 0;
return li > ri ? 1 : -1;
}
throw logic_error("unexpected identifier types: " + to_string(static_cast<int>(l.second)) + ", " +
to_string(static_cast<int>(r.second)));
}
// Compare numeric prerelease identifiers.
inline int cmp_num_prerel_ids(const string& l, const string& r) {
int li = stoi(l);
int ri = stoi(r);
if (li == ri) return 0;
return li > ri ? 1 : -1;
}
using Prerel_types = pair<Identifier_type, Identifier_type>;
using Prerel_id_comparator = function<int(const string&, const string&)>;
const map<Prerel_types, Prerel_id_comparator> comparators = {
{ { Identifier_type::alnum, Identifier_type::alnum }, cmp_alnum_prerel_ids },
{ { Identifier_type::alnum, Identifier_type::num }, [](const string&, const string&) {return 1;} },
{ { Identifier_type::num, Identifier_type::alnum }, [](const string&, const string&) {return -1;} },
{ { Identifier_type::num, Identifier_type::num }, cmp_num_prerel_ids }
};
// Compare prerelease identifiers based on their types.
int compare_prerel_identifiers(const Prerelease_identifier& l, const Prerelease_identifier& r) {
auto cmp = comparators.at({ l.second, r.second });
return cmp(l.first, r.first);
}
inline int cmp_rel_prerel(const Prerelease_identifiers& l, const Prerelease_identifiers& r) {
if (l.empty() && !r.empty()) return 1;
if (r.empty() && !l.empty()) return -1;
return 0;
}
}
namespace version {
int Semver200_comparator::compare(const Version_data& l, const Version_data& r) const {
// Compare normal version components.
int cmp = compare_normal(l, r);
if (cmp != 0) return cmp;
// release version is always higher than prerelease
if (l.prerelease_ids.empty() && !r.prerelease_ids.empty()) return 1;
if (r.prerelease_ids.empty() && !l.prerelease_ids.empty()) return -1;
// Compare if one version is release and the other prerelease; release is always higher than prerelease.
cmp = cmp_rel_prerel(l.prerelease_ids, r.prerelease_ids);
if (cmp != 0) return cmp;
// compare prerelease by looking at each identifier: numeric ones are compared as numbers,
// alphanum as ASCII strings
// Compare prerelease by looking at each identifier: numeric ones are compared as numbers,
// alphanum as ASCII strings.
auto shorter = min(l.prerelease_ids.size(), r.prerelease_ids.size());
for (size_t i = 0; i < shorter; i++) {
cmp = compare_prerel_identifiers(l.prerelease_ids[i], r.prerelease_ids[i]);
if (cmp != 0) return cmp;
}
// prerels are the same, to the length of the shorter one;
// if they are the same length, then versions are equal, otherwise, longer wins
// Prerelease identifiers are the same, to the length of the shorter version string;
// if they are the same length, then versions are equal, otherwise, longer one wins.
if (l.prerelease_ids.size() == r.prerelease_ids.size()) return 0;
return l.prerelease_ids.size() > r.prerelease_ids.size() ? 1 : -1;
}