Add MustParse

Closes #14

semver.go

@@ -285,6 +285,15 @@ func Parse(s string) (Version, error) {
 	return v, nil
 }
 
+// MustParse is like Parse but panics if the version cannot be parsed.
+func MustParse(s string) Version {
+	v, err := Parse(s)
+	if err != nil {
+		panic(`semver: Parse(` + s + `): ` + err.Error())
+	}
+	return v
+}
+
 // PreRelease Version
 type PRVersion struct {
 	VersionStr string

semver_test.go

@@ -50,6 +50,19 @@ func TestParse(t *testing.T) {
 	}
 }
 
+func TestMustParse(t *testing.T) {
+	_ = MustParse("32.2.1-alpha")
+}
+
+func TestMustParse_panic(t *testing.T) {
+	defer func() {
+		if recover() == nil {
+			t.Errorf("Should have panicked")
+		}
+	}()
+	_ = MustParse("invalid version")
+}
+
 func TestValidate(t *testing.T) {
 	for _, test := range formatTests {
 		if err := test.v.Validate(); err != nil {