stdlib/binascii: first import

Signed-off-by: Sebastien Binet <[email protected]>

Author: sbinet

stdlib/binascii/binascii.go

@@ -0,0 +1,89 @@
+// Copyright 2022 The go-python Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package binascii provides the implementation of the python's 'binascii' module.
+package binascii
+
+import (
+	"encoding/base64"
+	"hash/crc32"
+
+	"github.com/go-python/gpython/py"
+)
+
+var (
+	Incomplete = py.ExceptionType.NewType("binascii.Incomplete", "", nil, nil)
+	Error      = py.ValueError.NewType("binascii.Error", "", nil, nil)
+)
+
+func init() {
+	py.RegisterModule(&py.ModuleImpl{
+		Info: py.ModuleInfo{
+			Name: "binascii",
+			Doc:  "Conversion between binary data and ASCII",
+		},
+		Methods: []*py.Method{
+			py.MustNewMethod("a2b_base64", a2b_base64, 0, "Decode a line of base64 data."),
+			py.MustNewMethod("b2a_base64", b2a_base64, 0, "Base64-code line of data."),
+			py.MustNewMethod("crc32", crc32_, 0, "Compute CRC-32 incrementally."),
+		},
+		Globals: py.StringDict{
+			"Incomplete": Incomplete,
+			"Error":      Error,
+		},
+	})
+}
+
+func b2a_base64(self py.Object, args py.Tuple, kwargs py.StringDict) (py.Object, error) {
+	var (
+		pydata py.Object
+		pynewl py.Object = py.True
+	)
+	err := py.ParseTupleAndKeywords(args, kwargs, "y*|p:binascii.b2a_base64", []string{"data", "newline"}, &pydata, &pynewl)
+	if err != nil {
+		return nil, err
+	}
+
+	var (
+		buf     = []byte(pydata.(py.Bytes))
+		newline = bool(pynewl.(py.Bool))
+	)
+
+	out := base64.StdEncoding.EncodeToString(buf)
+	if newline {
+		out += "\n"
+	}
+	return py.Bytes(out), nil
+}
+
+func a2b_base64(self py.Object, args py.Tuple) (py.Object, error) {
+	var pydata py.Object
+	err := py.ParseTuple(args, "s:binascii.a2b_base64", &pydata)
+	if err != nil {
+		return nil, err
+	}
+
+	out, err := base64.StdEncoding.DecodeString(string(pydata.(py.String)))
+	if err != nil {
+		return nil, py.ExceptionNewf(Error, "could not decode base64 data: %+v", err)
+	}
+
+	return py.Bytes(out), nil
+}
+
+func crc32_(self py.Object, args py.Tuple) (py.Object, error) {
+	var (
+		pydata py.Object
+		pycrc  py.Object = py.Int(0)
+	)
+
+	err := py.ParseTuple(args, "y*|i:binascii.crc32", &pydata, &pycrc)
+	if err != nil {
+		return nil, err
+	}
+
+	crc := crc32.Update(uint32(pycrc.(py.Int)), crc32.IEEETable, []byte(pydata.(py.Bytes)))
+	return py.Int(crc), nil
+
+}

stdlib/binascii/binascii_test.go

@@ -0,0 +1,15 @@
+// Copyright 2022 The go-python Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package binascii_test
+
+import (
+	"testing"
+
+	"github.com/go-python/gpython/pytest"
+)
+
+func TestBinascii(t *testing.T) {
+	pytest.RunScript(t, "./testdata/test.py")
+}

stdlib/binascii/testdata/test.py

@@ -0,0 +1,34 @@
+# Copyright 2022 The go-python Authors.  All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+import binascii
+
+print("globals:")
+for name in ("Error", "Incomplete"):
+    v = getattr(binascii, name)
+    print("\nbinascii.%s:\n%s" % (name,repr(v)))
+
+def assertEqual(x, y):
+    assert x == y, "got: %s, want: %s" % (repr(x), repr(y))
+
+## base64
+assertEqual(binascii.b2a_base64(b'hello world!'), b'aGVsbG8gd29ybGQh\n')
+assertEqual(binascii.b2a_base64(b'hello\nworld!'), b'aGVsbG8Kd29ybGQh\n')
+assertEqual(binascii.b2a_base64(b'hello world!', newline=False), b'aGVsbG8gd29ybGQh')
+assertEqual(binascii.b2a_base64(b'hello\nworld!', newline=False), b'aGVsbG8Kd29ybGQh')
+assertEqual(binascii.a2b_base64("aGVsbG8gd29ybGQh\n"), b'hello world!')
+
+try:
+    binascii.b2a_base64("string")
+    print("expected an exception")
+except TypeError as e:
+    print("expected an exception:", e)
+    pass
+
+## crc32
+assertEqual(binascii.crc32(b'hello world!'), 62177901)
+assertEqual(binascii.crc32(b'hello world!', 0), 62177901)
+assertEqual(binascii.crc32(b'hello world!', 42), 4055036404)
+
+print("done.")

stdlib/binascii/testdata/test_golden.txt

@@ -0,0 +1,9 @@
+globals:
+
+binascii.Error:
+<class 'binascii.Error'>
+
+binascii.Incomplete:
+<class 'binascii.Incomplete'>
+expected an exception: binascii.b2a_base64() argument 1 must be bytes-like, not str
+done.

stdlib/stdlib.go

@@ -18,6 +18,7 @@ import (
 	"github.com/go-python/gpython/stdlib/marshal"
 	"github.com/go-python/gpython/vm"
 
+	_ "github.com/go-python/gpython/stdlib/binascii"
 	_ "github.com/go-python/gpython/stdlib/builtin"
 	_ "github.com/go-python/gpython/stdlib/math"
 	_ "github.com/go-python/gpython/stdlib/string"