Add user ID localpart encoding/decoding

userids_test.go

@@ -0,0 +1,64 @@
+package gomatrix
+
+import (
+	"testing"
+)
+
+var useridtests = []struct {
+	Input  string
+	Output string
+}{
+	{"Alph@Bet_50up", "_alph=40_bet__50up"},     // The doc example
+	{"abcdef", "abcdef"},                        // no-op
+	{"i_like_pie_", "i__like__pie__"},           // double underscore escaping
+	{"ABCDEF", "_a_b_c_d_e_f"},                  // all-caps
+	{"!£", "=21=c2=a3"},                         // punctuation and outside ascii range (U+00A3 => c2 a3)
+	{"___", "______"},                           // literal underscores
+	{"hello-world.", "hello-world."},            // allowed punctuation
+	{"5+5=10", "5=2b5=3d10"},                    // equals sign
+	{"東方Project", "=e6=9d=b1=e6=96=b9_project"}, // CJK mixed
+	{"	foo bar", "=09foo=20bar"}, // whitespace (tab and space)
+}
+
+func TestEncodeUserLocalpart(t *testing.T) {
+	for _, u := range useridtests {
+		out := EncodeUserLocalpart(u.Input)
+		if out != u.Output {
+			t.Fatalf("TestEncodeUserLocalpart(%s) => Got: %s Expected: %s", u.Input, out, u.Output)
+		}
+	}
+}
+
+func TestDecodeUserLocalpart(t *testing.T) {
+	for _, u := range useridtests {
+		in, _ := DecodeUserLocalpart(u.Output)
+		if in != u.Input {
+			t.Fatalf("TestDecodeUserLocalpart(%s) => Got: %s Expected: %s", u.Output, in, u.Input)
+		}
+	}
+}
+
+var errtests = []struct {
+	Input string
+}{
+	{"foo@bar"},         // invalid character @
+	{"foo_5bar"},        // invalid character after _
+	{"foo_._-bar"},      // multiple invalid characters after _
+	{"foo=2Hbar"},       // invalid hex after =
+	{"foo=2hbar"},       // invalid hex after = (lower-case)
+	{"foo=======2fbar"}, // multiple invalid hex after =
+	{"foo=2"},           // end of string after =
+	{"foo_"},            // end of string after _
+}
+
+func TestDecodeUserLocalpartErrors(t *testing.T) {
+	for _, u := range errtests {
+		out, err := DecodeUserLocalpart(u.Input)
+		if out != "" {
+			t.Fatalf("TestDecodeUserLocalpartErrors(%s) => Got: %s Expected: empty string", u.Input, out)
+		}
+		if err == nil {
+			t.Fatalf("TestDecodeUserLocalpartErrors(%s) => Got: nil error Expected: error", u.Input)
+		}
+	}
+}