Merge pull request #5 from phsmit/initialisms

Map initialisms in a nice way

mapper.go

@@ -152,6 +152,107 @@ func (mapper SnakeMapper) TableName(t string) string {
 	return t
 }
 
+// GonicMapper implements IMapper. It will consider initialisms when mapping names.
+// E.g. id -> ID, user -> User and to table names: UserID -> user_id, MyUID -> my_uid
+type GonicMapper map[string]bool
+
+func isASCIIUpper(r rune) bool {
+	return 'A' <= r && r <= 'Z'
+}
+
+func toASCIIUpper(r rune) rune {
+	if 'a' <= r && r <= 'z' {
+		r -= ('a' - 'A')
+	}
+	return r
+}
+
+func gonicCasedName(name string) string {
+	newstr := make([]rune, 0, len(name)+3)
+	for idx, chr := range name {
+		if isASCIIUpper(chr) && idx > 0 {
+			if !isASCIIUpper(newstr[len(newstr)-1]) {
+				newstr = append(newstr, '_')
+			}
+		}
+
+		if !isASCIIUpper(chr) && idx > 1 {
+			l := len(newstr)
+			if isASCIIUpper(newstr[l-1]) && isASCIIUpper(newstr[l-2]) {
+				newstr = append(newstr, newstr[l-1])
+				newstr[l-1] = '_'
+			}
+		}
+
+		newstr = append(newstr, chr)
+	}
+	return strings.ToLower(string(newstr))
+}
+
+func (mapper GonicMapper) Obj2Table(name string) string {
+	return gonicCasedName(name)
+}
+
+func (mapper GonicMapper) Table2Obj(name string) string {
+	newstr := make([]rune, 0)
+
+	name = strings.ToLower(name)
+	parts := strings.Split(name, "_")
+
+	for _, p := range parts {
+		_, isInitialism := mapper[strings.ToUpper(p)]
+		for i, r := range p {
+			if i == 0 || isInitialism {
+				r = toASCIIUpper(r)
+			}
+			newstr = append(newstr, r)
+		}
+	}
+
+	return string(newstr)
+}
+
+func (mapper GonicMapper) TableName(t string) string {
+	return t
+}
+
+// A GonicMapper that contains a list of common initialisms taken from golang/lint
+var LintGonicMapper = GonicMapper{
+	"API":   true,
+	"ASCII": true,
+	"CPU":   true,
+	"CSS":   true,
+	"DNS":   true,
+	"EOF":   true,
+	"GUID":  true,
+	"HTML":  true,
+	"HTTP":  true,
+	"HTTPS": true,
+	"ID":    true,
+	"IP":    true,
+	"JSON":  true,
+	"LHS":   true,
+	"QPS":   true,
+	"RAM":   true,
+	"RHS":   true,
+	"RPC":   true,
+	"SLA":   true,
+	"SMTP":  true,
+	"SSH":   true,
+	"TLS":   true,
+	"TTL":   true,
+	"UI":    true,
+	"UID":   true,
+	"UUID":  true,
+	"URI":   true,
+	"URL":   true,
+	"UTF8":  true,
+	"VM":    true,
+	"XML":   true,
+	"XSRF":  true,
+	"XSS":   true,
+}
+
 // provide prefix table name support
 type PrefixMapper struct {
 	Mapper IMapper

mapper_test.go

@@ -0,0 +1,45 @@
+package core
+
+import (
+	"testing"
+)
+
+func TestGonicMapperFromObj(t *testing.T) {
+	testCases := map[string]string{
+		"HTTPLib":             "http_lib",
+		"id":                  "id",
+		"ID":                  "id",
+		"IDa":                 "i_da",
+		"iDa":                 "i_da",
+		"IDAa":                "id_aa",
+		"aID":                 "a_id",
+		"aaID":                "aa_id",
+		"aaaID":               "aaa_id",
+		"MyREalFunkYLONgNAME": "my_r_eal_funk_ylo_ng_name",
+	}
+
+	for in, expected := range testCases {
+		out := gonicCasedName(in)
+		if out != expected {
+			t.Errorf("Given %s, expected %s but got %s", in, expected, out)
+		}
+	}
+}
+
+func TestGonicMapperToObj(t *testing.T) {
+	testCases := map[string]string{
+		"http_lib":                  "HTTPLib",
+		"id":                        "ID",
+		"ida":                       "Ida",
+		"id_aa":                     "IDAa",
+		"aa_id":                     "AaID",
+		"my_r_eal_funk_ylo_ng_name": "MyREalFunkYloNgName",
+	}
+
+	for in, expected := range testCases {
+		out := LintGonicMapper.Table2Obj(in)
+		if out != expected {
+			t.Errorf("Given %s, expected %s but got %s", in, expected, out)
+		}
+	}
+}