From dc78de3ddab1970b68e4b70a72a90785ab95548f Mon Sep 17 00:00:00 2001
From: Tulir Asokan <tulir@maunium.net>
Date: Wed, 7 Jan 2026 00:36:59 +0200
Subject: [PATCH] event: add tests for parseQuoted

---
 event/botcommandparse.go                  |  2 +-
 event/botcommandparse_test.go             | 67 +++++++++++++++++++++++
 event/botcommandtestdata/data.go          | 14 +++++
 event/botcommandtestdata/parse_quote.json | 20 +++++++
 4 files changed, 102 insertions(+), 1 deletion(-)
 create mode 100644 event/botcommandparse_test.go
 create mode 100644 event/botcommandtestdata/data.go
 create mode 100644 event/botcommandtestdata/parse_quote.json

diff --git a/event/botcommandparse.go b/event/botcommandparse.go
index 53681e5f..17f38664 100644
--- a/event/botcommandparse.go
+++ b/event/botcommandparse.go
@@ -45,7 +45,7 @@ func parseQuoted(val string) (parsed, remaining string, quoted bool) {
 				buf.WriteByte(val[escapeIdx+1])
 			}
 			val = val[min(escapeIdx+2, len(val)):]
-		} else if quoteIdx > 0 {
+		} else if quoteIdx >= 0 {
 			buf.WriteString(val[:quoteIdx])
 			val = val[quoteIdx+1:]
 			break
diff --git a/event/botcommandparse_test.go b/event/botcommandparse_test.go
new file mode 100644
index 00000000..611c055a
--- /dev/null
+++ b/event/botcommandparse_test.go
@@ -0,0 +1,67 @@
+// Copyright (c) 2026 Tulir Asokan
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package event
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"go.mau.fi/util/exerrors"
+
+	"maunium.net/go/mautrix/event/botcommandtestdata"
+)
+
+type QuoteParseOutput struct {
+	Parsed    string
+	Remaining string
+	Quoted    bool
+}
+
+type QuoteParseTestData struct {
+	Name   string
+	Input  string
+	Output QuoteParseOutput
+}
+
+func (qptd *QuoteParseTestData) UnmarshalJSON(data []byte) error {
+	var arr []any
+	if err := json.Unmarshal(data, &arr); err != nil {
+		return err
+	}
+	qptd.Name = arr[0].(string)
+	qptd.Input = arr[1].(string)
+	output := arr[2].([]any)
+	qptd.Output.Parsed = output[0].(string)
+	qptd.Output.Remaining = output[1].(string)
+	qptd.Output.Quoted = output[2].(bool)
+	return nil
+}
+
+func TestParseQuoted(t *testing.T) {
+	var qptd []QuoteParseTestData
+	dec := json.NewDecoder(exerrors.Must(botcommandtestdata.FS.Open("parse_quote.json")))
+	exerrors.PanicIfNotNil(dec.Decode(&qptd))
+	for _, test := range qptd {
+		t.Run(test.Name, func(t *testing.T) {
+			parsed, remaining, quoted := parseQuoted(test.Input)
+			assert.Equalf(t, test.Output, QuoteParseOutput{
+				Parsed:    parsed,
+				Remaining: remaining,
+				Quoted:    quoted,
+			}, "Failed with input `%s`", test.Input)
+			// Note: can't just test that requoted == input, because some inputs
+			// have unnecessary escapes which won't survive roundtripping
+			t.Run("roundtrip", func(t *testing.T) {
+				requoted := quoteString(parsed) + " " + remaining
+				reparsed, newRemaining, _ := parseQuoted(requoted)
+				assert.Equal(t, parsed, reparsed)
+				assert.Equal(t, remaining, newRemaining)
+			})
+		})
+	}
+}
diff --git a/event/botcommandtestdata/data.go b/event/botcommandtestdata/data.go
new file mode 100644
index 00000000..14119b97
--- /dev/null
+++ b/event/botcommandtestdata/data.go
@@ -0,0 +1,14 @@
+// Copyright (c) 2026 Tulir Asokan
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package botcommandtestdata
+
+import (
+	"embed"
+)
+
+//go:embed *
+var FS embed.FS
diff --git a/event/botcommandtestdata/parse_quote.json b/event/botcommandtestdata/parse_quote.json
new file mode 100644
index 00000000..dd2e17c5
--- /dev/null
+++ b/event/botcommandtestdata/parse_quote.json
@@ -0,0 +1,20 @@
+[
+	["single word", "meow", ["meow", "", false]],
+	["two words", "meow woof", ["meow", "woof", false]],
+	["many words", "meow meow mrrp", ["meow", "meow mrrp", false]],
+	["extra spaces", "meow    meow   mrrp", ["meow", "meow   mrrp", false]],
+	["trailing space", "meow    ", ["meow", "", false]],
+	["quoted word", "\"meow\" meow mrrp", ["meow", "meow mrrp", true]],
+	["quoted words", "\"meow meow\" mrrp", ["meow meow", "mrrp", true]],
+	["spaces in quotes", "\" meow  meow \"  mrrp", [" meow  meow ", "mrrp", true]],
+	["quotes after word", "meow  \" meow mrrp \"", ["meow", "\" meow mrrp \"", false]],
+	["escaped quote", "\"meow\\\" meow\" mrrp", ["meow\" meow", "mrrp", true]],
+	["missing end quote", "\"meow meow mrrp", ["meow meow mrrp", "", true]],
+	["missing end quote with escaped quote", "\"meow\\\" meow mrrp", ["meow\" meow mrrp", "", true]],
+	["quote in the middle", "me\"ow meow mrrp", ["me\"ow", "meow mrrp", false]],
+	["backslash in the middle", "me\\ow meow mrrp", ["me\\ow", "meow mrrp", false]],
+	["other escaped character", "\"m\\eow\" meow mrrp", ["meow", "meow mrrp", true]],
+	["escaped backslashes", "\"m\\\\e\\\"ow\\\\\" meow mrrp", ["m\\e\"ow\\", "meow mrrp", true]],
+	["just quotes", "\"\\\"\\\"\\\\\\\"\" meow", ["\"\"\\\"", "meow", true]],
+	["eof escape", "\"meow\\", ["meow\\", "", true]]
+]