Merge pull request #24 from NathanBaulch/master

Better number handling and general performance

acronyms.go

@@ -1,5 +1,5 @@
 package strcase
 
-var uppercaseAcronym = map[string]bool{
+var uppercaseAcronym = map[string]string{
-	"ID": true,
+	"ID": "id",
 }

camel.go

@@ -31,51 +31,49 @@ import (
 
 // Converts a string to CamelCase
 func toCamelInitCase(s string, initCase bool) string {
-	s = addWordBoundariesToNumbers(s)
+	if s == "" {
-	s = strings.Trim(s, " ")
+		return s
-	n := ""
+	}
+	if a, ok := uppercaseAcronym[s]; ok {
+		s = a
+	}
+
+	n := strings.Builder{}
+	n.Grow(len(s))
 	capNext := initCase
-	for _, v := range s {
+	for i, v := range []byte(s) {
-		if v >= 'A' && v <= 'Z' {
+		vIsCap := v >= 'A' && v <= 'Z'
-			n += string(v)
+		vIsLow := v >= 'a' && v <= 'z'
-		}
+		if capNext {
-		if v >= '0' && v <= '9' {
+			if vIsLow {
-			n += string(v)
+				v += 'A'
-		}
+				v -= 'a'
-		if v >= 'a' && v <= 'z' {
+			}
-			if capNext {
+		} else if i == 0 {
-				n += strings.ToUpper(string(v))
+			if vIsCap {
-			} else {
+				v += 'a'
-				n += string(v)
+				v -= 'A'
 			}
 		}
-		if v == '_' || v == ' ' || v == '-' || v == '.' {
+		if vIsCap || vIsLow {
+			n.WriteByte(v)
+			capNext = false
+		} else if vIsNum := v >= '0' && v <= '9'; vIsNum {
+			n.WriteByte(v)
 			capNext = true
 		} else {
-			capNext = false
+			capNext = v == '_' || v == ' ' || v == '-' || v == '.'
 		}
 	}
-	return n
+	return n.String()
 }
 
 // ToCamel converts a string to CamelCase
 func ToCamel(s string) string {
-	if uppercaseAcronym[s] {
-		s = strings.ToLower(s)
-	}
 	return toCamelInitCase(s, true)
 }
 
 // ToLowerCamel converts a string to lowerCamelCase
 func ToLowerCamel(s string) string {
-	if s == "" {
-		return s
-	}
-	if uppercaseAcronym[s] {
-		s = strings.ToLower(s)
-	}
-	if r := rune(s[0]); r >= 'A' && r <= 'Z' {
-		s = strings.ToLower(string(r)) + s[1:]
-	}
 	return toCamelInitCase(s, false)
 }

camel_test.go

@@ -28,7 +28,7 @@ import (
 	"testing"
 )
 
-func TestToCamel(t *testing.T) {
+func toCamel(tb testing.TB) {
 	cases := [][]string{
 		{"test_case", "TestCase"},
 		{"test.case", "TestCase"},
@@ -47,12 +47,20 @@ func TestToCamel(t *testing.T) {
 		out := i[1]
 		result := ToCamel(in)
 		if result != out {
-			t.Error("'" + result + "' != '" + out + "'")
+			tb.Errorf("%q (%q != %q)", in, result, out)
 		}
 	}
 }
 
-func TestToLowerCamel(t *testing.T) {
+func TestToCamel(t *testing.T) {
+	toCamel(t)
+}
+
+func BenchmarkToCamel(b *testing.B) {
+	benchmarkCamelTest(b, toCamel)
+}
+
+func toLowerCamel(tb testing.TB) {
 	cases := [][]string{
 		{"foo-bar", "fooBar"},
 		{"TestCase", "testCase"},
@@ -66,7 +74,21 @@ func TestToLowerCamel(t *testing.T) {
 		out := i[1]
 		result := ToLowerCamel(in)
 		if result != out {
-			t.Error("'" + result + "' != '" + out + "'")
+			tb.Errorf("%q (%q != %q)", in, result, out)
 		}
 	}
 }
+
+func TestToLowerCamel(t *testing.T) {
+	toLowerCamel(t)
+}
+
+func BenchmarkToLowerCamel(b *testing.B) {
+	benchmarkCamelTest(b, toLowerCamel)
+}
+
+func benchmarkCamelTest(b *testing.B, fn func(testing.TB)) {
+	for n := 0; n < b.N; n++ {
+		fn(b)
+	}
+}

numbers.go

@@ -1,38 +0,0 @@
-/*
- * The MIT License (MIT)
- *
- * Copyright (c) 2015 Ian Coleman
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, Subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or Substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package strcase
-
-import (
-	"regexp"
-)
-
-var numberSequence = regexp.MustCompile(`([a-zA-Z])(\d+)([a-zA-Z]?)`)
-var numberReplacement = []byte(`$1 $2 $3`)
-
-func addWordBoundariesToNumbers(s string) string {
-	b := []byte(s)
-	b = numberSequence.ReplaceAll(b, numberReplacement)
-	return string(b)
-}

snake.go

@@ -31,11 +31,10 @@ import (
 
 // ToSnake converts a string to snake_case
 func ToSnake(s string) string {
-
 	return ToDelimited(s, '_')
 }
-func ToSnakeWithIgnore(s string, ignore uint8) string {
 
+func ToSnakeWithIgnore(s string, ignore uint8) string {
 	return ToScreamingDelimited(s, '_', ignore, false)
 }
 
@@ -65,49 +64,68 @@ func ToDelimited(s string, delimiter uint8) string {
 // or delimited.snake.case
 // (in this case `delimiter = '.'; screaming = false`)
 func ToScreamingDelimited(s string, delimiter uint8, ignore uint8, screaming bool) string {
-	s = addWordBoundariesToNumbers(s)
+	n := strings.Builder{}
-	s = strings.Trim(s, " ")
+	n.Grow(len(s) + 2) // nominal 2 bytes of extra space for inserted delimiters
-	n := ""
+	start := true
-	for i, v := range s {
+	spaces := 0
+	for i, v := range []byte(s) {
+		if v == ' ' {
+			spaces++
+			continue
+		} else if start {
+			start = false
+			spaces = 0
+		} else {
+			for ; spaces > 0; spaces-- {
+				if ignore == ' ' {
+					n.WriteByte(' ')
+				} else {
+					n.WriteByte(delimiter)
+				}
+			}
+		}
+
+		vIsCap := v >= 'A' && v <= 'Z'
+		vIsLow := v >= 'a' && v <= 'z'
+		if vIsLow && screaming {
+			v += 'A'
+			v -= 'a'
+		} else if vIsCap && !screaming {
+			v += 'a'
+			v -= 'A'
+		}
+
 		// treat acronyms as words, eg for JSONData -> JSON is a whole word
-		nextCaseIsChanged := false
 		if i+1 < len(s) {
 			next := s[i+1]
-			vIsCap := v >= 'A' && v <= 'Z'
+			vIsNum := v >= '0' && v <= '9'
-			vIsLow := v >= 'a' && v <= 'z'
 			nextIsCap := next >= 'A' && next <= 'Z'
 			nextIsLow := next >= 'a' && next <= 'z'
-			if (vIsCap && nextIsLow) || (vIsLow && nextIsCap) {
+			nextIsNum := next >= '0' && next <= '9'
-				nextCaseIsChanged = true
-			}
-			if ignore > 0 && i-1 >= 0 && s[i-1] == ignore && nextCaseIsChanged {
-				nextCaseIsChanged = false
-			}
-		}
-
-		if i > 0 && n[len(n)-1] != delimiter && nextCaseIsChanged {
 			// add underscore if next letter case type is changed
-			if v >= 'A' && v <= 'Z' {
+			if (vIsCap && (nextIsLow || nextIsNum)) || (vIsLow && (nextIsCap || nextIsNum)) || (vIsNum && (nextIsCap || nextIsLow)) {
-				n += string(delimiter) + string(v)
+				if prevIgnore := ignore > 0 && i > 0 && s[i-1] == ignore; !prevIgnore {
-			} else if v >= 'a' && v <= 'z' {
+					if vIsCap && nextIsLow {
-				n += string(v) + string(delimiter)
+						if prevIsCap := i > 0 && s[i-1] >= 'A' && s[i-1] <= 'Z'; prevIsCap {
-			}
+							n.WriteByte(delimiter)
-		} else if v == ' ' || v == '_' || v == '-' {
+						}
-			// replace spaces/underscores with delimiters
+					}
-			if uint8(v) == ignore {
+					n.WriteByte(v)
-				n += string(v)
+					if vIsLow || vIsNum || nextIsNum {
-			} else {
+						n.WriteByte(delimiter)
-				n += string(delimiter)
+					}
+					continue
+				}
 			}
+		}
+
+		if (v == ' ' || v == '_' || v == '-') && uint8(v) != ignore {
+			// replace space/underscore/hyphen with delimiter
+			n.WriteByte(delimiter)
 		} else {
-			n = n + string(v)
+			n.WriteByte(v)
 		}
 	}
 
-	if screaming {
+	return n.String()
-		n = strings.ToUpper(n)
-	} else {
-		n = strings.ToLower(n)
-	}
-	return n
 }

snake_test.go

@@ -29,7 +29,7 @@ import (
 	"testing"
 )
 
-func TestToSnake(t *testing.T) {
+func toSnake(tb testing.TB) {
 	cases := [][]string{
 		{"testCase", "test_case"},
 		{"TestCase", "test_case"},
@@ -48,17 +48,30 @@ func TestToSnake(t *testing.T) {
 		{"JSONData", "json_data"},
 		{"userID", "user_id"},
 		{"AAAbbb", "aa_abbb"},
+		{"1A2", "1_a_2"},
+		{"A1B", "a_1_b"},
+		{"A1A2A3", "a_1_a_2_a_3"},
+		{"A1 A2 A3", "a_1_a_2_a_3"},
+		{"AB1AB2AB3", "ab_1_ab_2_ab_3"},
+		{"AB1 AB2 AB3", "ab_1_ab_2_ab_3"},
 	}
 	for _, i := range cases {
 		in := i[0]
 		out := i[1]
 		result := ToSnake(in)
 		if result != out {
-			t.Error("'" + in + "'('" + result + "' != '" + out + "')")
+			tb.Errorf("%q (%q != %q)", in, result, out)
 		}
 	}
 }
-func TestToSnakeWithIgnore(t *testing.T) {
+
+func TestToSnake(t *testing.T) { toSnake(t) }
+
+func BenchmarkToSnake(b *testing.B) {
+	benchmarkSnakeTest(b, toSnake)
+}
+
+func toSnakeWithIgnore(tb testing.TB) {
 	cases := [][]string{
 		{"testCase", "test_case"},
 		{"TestCase", "test_case"},
@@ -75,9 +88,9 @@ func TestToSnakeWithIgnore(t *testing.T) {
 		{"AnyKind of_string", "any_kind_of_string"},
 		{"numbers2and55with000", "numbers_2_and_55_with_000"},
 		{"JSONData", "json_data"},
-		{"AwesomeAcitvity.UserID", "awesome_acitvity.user_id", "."},
+		{"AwesomeActivity.UserID", "awesome_activity.user_id", "."},
-		{"AwesomeAcitvity.User.Id", "awesome_acitvity.user.id", "."},
+		{"AwesomeActivity.User.Id", "awesome_activity.user.id", "."},
-		{"AwesomeUsername@Awesome.Com", "awesome_username@awesome._com", "@"},
+		{"AwesomeUsername@Awesome.Com", "awesome_username@awesome.com", "@"},
 	}
 	for _, i := range cases {
 		in := i[0]
@@ -88,12 +101,22 @@ func TestToSnakeWithIgnore(t *testing.T) {
 		}
 		result := ToSnakeWithIgnore(in, ignore)
 		if result != out {
-			t.Error("'" + in + "'('" + result + "' != '" + out + "')")
+			istr := ""
+			if len(i) == 3 {
+				istr = " ignoring '" + i[2] + "'"
+			}
+			tb.Errorf("%q (%q != %q%s)", in, result, out, istr)
 		}
 	}
 }
 
-func TestToDelimited(t *testing.T) {
+func TestToSnakeWithIgnore(t *testing.T) { toSnakeWithIgnore(t) }
+
+func BenchmarkToSnakeWithIgnore(b *testing.B) {
+	benchmarkSnakeTest(b, toSnakeWithIgnore)
+}
+
+func toDelimited(tb testing.TB) {
 	cases := [][]string{
 		{"testCase", "test@case"},
 		{"TestCase", "test@case"},
@@ -119,12 +142,18 @@ func TestToDelimited(t *testing.T) {
 		out := i[1]
 		result := ToDelimited(in, '@')
 		if result != out {
-			t.Error("'" + in + "' ('" + result + "' != '" + out + "')")
+			tb.Errorf("%q (%q != %q)", in, result, out)
 		}
 	}
 }
 
-func TestToScreamingSnake(t *testing.T) {
+func TestToDelimited(t *testing.T) { toDelimited(t) }
+
+func BenchmarkToDelimited(b *testing.B) {
+	benchmarkSnakeTest(b, toDelimited)
+}
+
+func toScreamingSnake(tb testing.TB) {
 	cases := [][]string{
 		{"testCase", "TEST_CASE"},
 	}
@@ -133,12 +162,18 @@ func TestToScreamingSnake(t *testing.T) {
 		out := i[1]
 		result := ToScreamingSnake(in)
 		if result != out {
-			t.Error("'" + result + "' != '" + out + "'")
+			tb.Errorf("%q (%q != %q)", in, result, out)
 		}
 	}
 }
 
-func TestToKebab(t *testing.T) {
+func TestToScreamingSnake(t *testing.T) { toScreamingSnake(t) }
+
+func BenchmarkToScreamingSnake(b *testing.B) {
+	benchmarkSnakeTest(b, toScreamingSnake)
+}
+
+func toKebab(tb testing.TB) {
 	cases := [][]string{
 		{"testCase", "test-case"},
 	}
@@ -147,12 +182,18 @@ func TestToKebab(t *testing.T) {
 		out := i[1]
 		result := ToKebab(in)
 		if result != out {
-			t.Error("'" + result + "' != '" + out + "'")
+			tb.Errorf("%q (%q != %q)", in, result, out)
 		}
 	}
 }
 
-func TestToScreamingKebab(t *testing.T) {
+func TestToKebab(t *testing.T) { toKebab(t) }
+
+func BenchmarkToKebab(b *testing.B) {
+	benchmarkSnakeTest(b, toKebab)
+}
+
+func toScreamingKebab(tb testing.TB) {
 	cases := [][]string{
 		{"testCase", "TEST-CASE"},
 	}
@@ -161,12 +202,18 @@ func TestToScreamingKebab(t *testing.T) {
 		out := i[1]
 		result := ToScreamingKebab(in)
 		if result != out {
-			t.Error("'" + result + "' != '" + out + "'")
+			tb.Errorf("%q (%q != %q)", in, result, out)
 		}
 	}
 }
 
-func TestToScreamingDelimited(t *testing.T) {
+func TestToScreamingKebab(t *testing.T) { toScreamingKebab(t) }
+
+func BenchmarkToScreamingKebab(b *testing.B) {
+	benchmarkSnakeTest(b, toScreamingKebab)
+}
+
+func toScreamingDelimited(tb testing.TB) {
 	cases := [][]string{
 		{"testCase", "TEST.CASE"},
 	}
@@ -175,23 +222,45 @@ func TestToScreamingDelimited(t *testing.T) {
 		out := i[1]
 		result := ToScreamingDelimited(in, '.', 0, true)
 		if result != out {
-			t.Error("'" + result + "' != '" + out + "'")
+			tb.Errorf("%q (%q != %q)", in, result, out)
 		}
 	}
 }
 
-func TestToScreamingDelimitedWithIgnore(t *testing.T) {
+func TestToScreamingDelimited(t *testing.T) { toScreamingDelimited(t) }
+
+func BenchmarkToScreamingDelimited(b *testing.B) {
+	benchmarkSnakeTest(b, toScreamingDelimited)
+}
+
+func toScreamingDelimitedWithIgnore(tb testing.TB) {
 	cases := [][]string{
 		{"AnyKind of_string", "ANY.KIND OF.STRING", ".", " "},
 	}
 	for _, i := range cases {
 		in := i[0]
 		out := i[1]
-		delimiter := uint8(i[2][0])
+		delimiter := i[2][0]
-		ignore := uint8(i[3][0])
+		ignore := i[3][0]
 		result := ToScreamingDelimited(in, delimiter, ignore, true)
 		if result != out {
-			t.Error("'" + result + "' != '" + out + "'")
+			istr := ""
+			if len(i) == 4 {
+				istr = " ignoring '" + i[3] + "'"
+			}
+			tb.Errorf("%q (%q != %q%s)", in, result, out, istr)
 		}
 	}
 }
+
+func TestToScreamingDelimitedWithIgnore(t *testing.T) { toScreamingDelimitedWithIgnore(t) }
+
+func BenchmarkToScreamingDelimitedWithIgnore(b *testing.B) {
+	benchmarkSnakeTest(b, toScreamingDelimitedWithIgnore)
+}
+
+func benchmarkSnakeTest(b *testing.B, fn func(testing.TB)) {
+	for n := 0; n < b.N; n++ {
+		fn(b)
+	}
+}