From 92cf886eab5ffbab61db9cedc0829ea91ed578de Mon Sep 17 00:00:00 2001
From: Oleksii Holub <1935960+Tyrrrz@users.noreply.github.com>
Date: Thu, 25 Aug 2022 21:20:22 +0300
Subject: [PATCH] Fix not being able to parse message filters that share common
 prefix with one of the named filters

Related to #909
---
 .../Exporting/Filtering/Parsing/FilterGrammar.cs            | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/DiscordChatExporter.Core/Exporting/Filtering/Parsing/FilterGrammar.cs b/DiscordChatExporter.Core/Exporting/Filtering/Parsing/FilterGrammar.cs
index f7b3a31..675cd84 100644
--- a/DiscordChatExporter.Core/Exporting/Filtering/Parsing/FilterGrammar.cs
+++ b/DiscordChatExporter.Core/Exporting/Filtering/Parsing/FilterGrammar.cs
@@ -32,6 +32,7 @@ internal static class FilterGrammar
     private static readonly TextParser<MessageFilter> FromFilter =
         Span
             .EqualToIgnoreCase("from:")
+            .Try()
             .IgnoreThen(String)
             .Select(v => (MessageFilter)new FromMessageFilter(v))
             .Named("from:<value>");
@@ -39,6 +40,7 @@ internal static class FilterGrammar
     private static readonly TextParser<MessageFilter> MentionsFilter =
         Span
             .EqualToIgnoreCase("mentions:")
+            .Try()
             .IgnoreThen(String)
             .Select(v => (MessageFilter)new MentionsMessageFilter(v))
             .Named("mentions:<value>");
@@ -46,6 +48,7 @@ internal static class FilterGrammar
     private static readonly TextParser<MessageFilter> ReactionFilter =
         Span
             .EqualToIgnoreCase("reaction:")
+            .Try()
             .IgnoreThen(String)
             .Select(v => (MessageFilter)new ReactionMessageFilter(v))
             .Named("reaction:<value>");
@@ -53,6 +56,7 @@ internal static class FilterGrammar
     private static readonly TextParser<MessageFilter> HasFilter =
         Span
             .EqualToIgnoreCase("has:")
+            .Try()
             .IgnoreThen(Parse.OneOf(
                 Span.EqualToIgnoreCase("link").IgnoreThen(Parse.Return(MessageContentMatchKind.Link)),
                 Span.EqualToIgnoreCase("embed").IgnoreThen(Parse.Return(MessageContentMatchKind.Embed)),
@@ -65,6 +69,8 @@ internal static class FilterGrammar
             .Select(k => (MessageFilter)new HasMessageFilter(k))
             .Named("has:<value>");
 
+    // Make sure that property-based filters like 'has:link' don't prevent text like 'hello' from being parsed.
+    // https://github.com/Tyrrrz/DiscordChatExporter/issues/909
     private static readonly TextParser<MessageFilter> PrimitiveFilter =
         Parse.OneOf(
             FromFilter,