initial commits

errors.go

@@ -5,5 +5,6 @@ import (
 )
 
 const (
+	errNilReader = erorr.Error("rfc3986: nil reader")
 	errNilWriter = erorr.Error("rfc3986: nil writer")
 )

pctencoded.go

@@ -2,8 +2,95 @@ package rfc3986
 
 import (
 	"io"
+
+	"sourcecode.social/reiver/go-erorr"
 )
 
+func ReadPctEncodedByte(reader io.Reader) (byte, error) {
+	if nil == reader {
+		return 0, errNilReader
+	}
+
+	var buffer [1]byte
+	var p []byte = buffer[:]
+
+	{
+		const expected byte = '%'
+
+		n, err := reader.Read(p)
+		if nil != err {
+			return 0, erorr.Errorf("rfc3986: could not read the 1st byte in pct-encoded string because: %w", err)
+		}
+		if 1 != n {
+			return 0, erorr.Errorf("rfc3986: problem reading the 1st byte in pct-encoded string — expected to have read 1 byte but actually read %d bytes.", n)
+		}
+
+		actual := buffer[0]
+
+		if expected != actual {
+			return 0, erorr.Errorf("rfc3986:the 1st byte in pct-encoded string is not a percent-sign (%U) (%q) is actually %U (%q)", expected, expected, actual, actual)
+		}
+	}
+
+	var result byte = 0
+
+	{
+		n, err := reader.Read(p)
+		if nil != err {
+			return 0, erorr.Errorf("rfc3986: could not read the 2nd byte in pct-encoded string because: %w", err)
+		}
+		if 1 != n {
+			return 0, erorr.Errorf("rfc3986: problem reading the 2nd byte in pct-encoded string — expected to have read 1 byte but actually read %d bytes.", n)
+		}
+
+		b0 := buffer[0]
+
+		switch {
+		case '0' <= b0 && b0 <= '9':
+			b0 -= '0'
+		case 'A' <= b0 && b0 <= 'F':
+			b0 -= 'A'
+			b0 += 10
+		case 'a' <= b0 && b0 <= 'f':
+			b0 -= 'a'
+			b0 += 10
+		default:
+			return 0, erorr.Errorf("rfc3986: the 2nd byte in the pct-encoded string is not an IETF RFC-2234 'HEXDIG'")
+		}
+
+		result |= (b0 << 4)
+	}
+
+	{
+		n, err := reader.Read(p)
+		if nil != err {
+			return 0, erorr.Errorf("rfc3986: could not read the 3rd byte in pct-encoded string because: %w", err)
+		}
+		if 1 != n {
+			return 0, erorr.Errorf("rfc3986: problem reading the 3rd byte in pct-encoded string — expected to have read 1 byte but actually read %d bytes.", n)
+		}
+
+		b0 := buffer[0]
+
+		switch {
+		case '0' <= b0 && b0 <= '9':
+			b0 -= '0'
+		case 'A' <= b0 && b0 <= 'F':
+			b0 -= 'A'
+			b0 += 10
+		case 'a' <= b0 && b0 <= 'f':
+			b0 -= 'a'
+			b0 += 10
+		default:
+			return 0, erorr.Errorf("rfc3986: the 2nd byte in the pct-encoded string is not an IETF RFC-2234 'HEXDIG'")
+		}
+
+		result |= b0
+	}
+
+	return result, nil
+}
+
 func WritePctEncodedByte(writer io.Writer, b byte) error {
 	if nil == writer {
 		return errNilWriter

pctencoded_readpctencodedbyte_test.go

@@ -0,0 +1,345 @@
+package rfc3986_test
+
+import (
+	"testing"
+
+	"io"
+	"strings"
+
+	"sourcecode.social/reiver/go-rfc3986"
+)
+
+func TestReadPctEncodedByte(t *testing.T) {
+
+	tests := []struct{
+		Value string
+		Expected byte
+	}{
+		{
+			Value:    "%00",
+			Expected:    0,
+		},
+		{
+			Value:    "%01",
+			Expected:    1,
+		},
+		{
+			Value:    "%02",
+			Expected:    2,
+		},
+		{
+			Value:    "%03",
+			Expected:    3,
+		},
+		{
+			Value:    "%04",
+			Expected:    4,
+		},
+		{
+			Value:    "%05",
+			Expected:    5,
+		},
+		{
+			Value:    "%06",
+			Expected:    6,
+		},
+		{
+			Value:    "%07",
+			Expected:    7,
+		},
+		{
+			Value:    "%08",
+			Expected:    8,
+		},
+		{
+			Value:    "%09",
+			Expected:    9,
+		},
+		{
+			Value:    "%0A",
+			Expected:   10,
+		},
+		{
+			Value:    "%0B",
+			Expected:   11,
+		},
+		{
+			Value:    "%0C",
+			Expected:   12,
+		},
+		{
+			Value:    "%0D",
+			Expected:   13,
+		},
+		{
+			Value:    "%0E",
+			Expected:   14,
+		},
+		{
+			Value:    "%0F",
+			Expected:   15,
+		},
+
+
+
+		{
+			Value:    "%0a",
+			Expected:   10,
+		},
+		{
+			Value:    "%0b",
+			Expected:   11,
+		},
+		{
+			Value:    "%0c",
+			Expected:   12,
+		},
+		{
+			Value:    "%0d",
+			Expected:   13,
+		},
+		{
+			Value:    "%0e",
+			Expected:   14,
+		},
+		{
+			Value:    "%0f",
+			Expected:   15,
+		},
+
+
+
+		{
+			Value:    "%10",
+			Expected:   16,
+		},
+		{
+			Value:    "%11",
+			Expected:   17,
+		},
+		{
+			Value:    "%12",
+			Expected:   18,
+		},
+		{
+			Value:    "%13",
+			Expected:   19,
+		},
+		{
+			Value:    "%14",
+			Expected:   20,
+		},
+		{
+			Value:    "%15",
+			Expected:   21,
+		},
+		{
+			Value:    "%16",
+			Expected:   22,
+		},
+		{
+			Value:    "%17",
+			Expected:   23,
+		},
+		{
+			Value:    "%18",
+			Expected:   24,
+		},
+		{
+			Value:    "%19",
+			Expected:   25,
+		},
+		{
+			Value:    "%1A",
+			Expected:   26,
+		},
+		{
+			Value:    "%1B",
+			Expected:   27,
+		},
+		{
+			Value:    "%1C",
+			Expected:   28,
+		},
+		{
+			Value:    "%1D",
+			Expected:   29,
+		},
+		{
+			Value:    "%1E",
+			Expected:   30,
+		},
+		{
+			Value:    "%1F",
+			Expected:   31,
+		},
+
+
+
+		{
+			Value:    "%1a",
+			Expected:   26,
+		},
+		{
+			Value:    "%1b",
+			Expected:   27,
+		},
+		{
+			Value:    "%1c",
+			Expected:   28,
+		},
+		{
+			Value:    "%1d",
+			Expected:   29,
+		},
+		{
+			Value:    "%1e",
+			Expected:   30,
+		},
+		{
+			Value:    "%1f",
+			Expected:   31,
+		},
+
+
+
+		{
+			Value:    "%20F",
+			Expected:   32,
+		},
+
+
+
+		{
+			Value:    "%FA",
+			Expected:  250,
+		},
+		{
+			Value:    "%FB",
+			Expected:  251,
+		},
+		{
+			Value:    "%FC",
+			Expected:  252,
+		},
+		{
+			Value:    "%FD",
+			Expected:  253,
+		},
+		{
+			Value:    "%FE",
+			Expected:  254,
+		},
+		{
+			Value:    "%FF",
+			Expected:  255,
+		},
+
+
+
+		{
+			Value:    "%Fa",
+			Expected:  250,
+		},
+		{
+			Value:    "%Fb",
+			Expected:  251,
+		},
+		{
+			Value:    "%Fc",
+			Expected:  252,
+		},
+		{
+			Value:    "%Fd",
+			Expected:  253,
+		},
+		{
+			Value:    "%Fe",
+			Expected:  254,
+		},
+		{
+			Value:    "%Ff",
+			Expected:  255,
+		},
+
+
+
+		{
+			Value:    "%fA",
+			Expected:  250,
+		},
+		{
+			Value:    "%fB",
+			Expected:  251,
+		},
+		{
+			Value:    "%fC",
+			Expected:  252,
+		},
+		{
+			Value:    "%fD",
+			Expected:  253,
+		},
+		{
+			Value:    "%fE",
+			Expected:  254,
+		},
+		{
+			Value:    "%fF",
+			Expected:  255,
+		},
+
+
+
+		{
+			Value:    "%fa",
+			Expected:  250,
+		},
+		{
+			Value:    "%fb",
+			Expected:  251,
+		},
+		{
+			Value:    "%fc",
+			Expected:  252,
+		},
+		{
+			Value:    "%fd",
+			Expected:  253,
+		},
+		{
+			Value:    "%fe",
+			Expected:  254,
+		},
+		{
+			Value:    "%ff",
+			Expected:  255,
+		},
+	}
+
+	for testNumber, test := range tests {
+
+		var reader io.Reader = strings.NewReader(test.Value)
+
+		actual, err := rfc3986.ReadPctEncodedByte(reader)
+		if nil != err {
+			t.Errorf("For test #%d, did not expect an error but actually got one." , testNumber)
+			t.Logf("ERROR: (%T) %s", err, err)
+			t.Logf("VALUE: %q", test.Value)
+			t.Logf("EXPECTED: %d (0x%X)", test.Expected, test.Expected)
+			continue
+		}
+
+		{
+			expected := test.Expected
+
+			if expected != actual {
+				t.Errorf("For test #%d, the actual byte returned is not what was expected.", testNumber)
+				t.Logf("EXPECTED: %d (0x%X)", expected, expected)
+				t.Logf("ACTUAL:   %d (0x%X)", actual, actual)
+				t.Logf("VALUE: %q", test.Value)
+				continue
+			}
+		}
+	}
+}