feat:Add ascii85 coding tool class and test class (#104)

Author: qurenneng

gox/encodingx/ascii85x/ascii85x.go

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2022, AcmeStack
+ * All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ascii85x
+
+import (
+	"encoding/ascii85"
+)
+
+// Ascii85EncodeToInt ascii85x convert bytes to int
+func Ascii85EncodeToInt(dst, src []byte) int {
+	return ascii85.Encode(dst, src)
+}
+
+// Ascii85Decode ascii85x convert bytes and the number  to number of bytes
+func Ascii85Decode(dst, src []byte, flush bool) (ndst, nsrc int, err error) {
+	return ascii85.Decode(dst, src, flush)
+}
+
+// Ascii85MaxEncodedLenToInt ascii85x convert int to int
+func Ascii85MaxEncodedLenToInt(n int) int {
+	return ascii85.MaxEncodedLen(n)
+}

gox/encodingx/ascii85x/ascii85x_test.go

@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2022, AcmeStack
+ * All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ascii85x
+
+import "testing"
+
+var pairs = []struct {
+	decoded string
+	encoded string
+}{
+	{
+		"",
+		"",
+	},
+	{
+		"\000\000\000\000",
+		"z",
+	},
+}
+
+func TestAscii85EncodeToInt(t *testing.T) {
+	for _, p := range pairs {
+		buf := make([]byte, Ascii85MaxEncodedLenToInt(len(p.decoded)))
+		result := Ascii85EncodeToInt(buf, []byte(p.decoded))
+		buf = buf[0:result]
+		if strip85(string(buf)) != strip85(p.encoded) {
+			t.Errorf("TestAscii85EncodeToInt() result = %v, want %v", result, strip85(p.encoded))
+		}
+	}
+}
+
+func TestAscii85Decode(t *testing.T) {
+	for _, p := range pairs {
+		dbuf := make([]byte, 4*len(p.encoded))
+		ndst, nsrc, err := Ascii85Decode(dbuf, []byte(p.encoded), true)
+		if err != error(nil) {
+			t.Errorf("TestAscii85Decode() error = %v, want %v", err, error(nil))
+		}
+		if nsrc != len(p.encoded) {
+			t.Errorf("TestAscii85Decode() nsrc = %v, want %v", nsrc, len(p.encoded))
+		}
+		if ndst != len(p.decoded) {
+			t.Errorf("TestAscii85Decode() ndst = %v, want %v", ndst, len(p.decoded))
+		}
+		if string(dbuf[0:ndst]) != p.decoded {
+			t.Errorf("TestAscii85Decode() want %v", p.decoded)
+		}
+	}
+}
+
+func strip85(s string) string {
+	t := make([]byte, len(s))
+	w := 0
+	for r := 0; r < len(s); r++ {
+		c := s[r]
+		if c > ' ' {
+			t[w] = c
+			w++
+		}
+	}
+	return string(t[0:w])
+}