From 14471347a07a0f50ba42f427475bbec9fab4c26b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vin=C3=ADcius=20dos=20Santos=20Oliveira?=
 <vini.ipsmaker@gmail.com>
Date: Fri, 9 Jul 2021 16:00:03 -0300
Subject: [PATCH] Add failing tests for chunked parser

== RATIONALE

A chunked parser that failed to consume the next token means either:

1. Insufficient tokens. The user must buffer more and try again.
2. Invalid token.

There's nothing polemic about the first case. As for the second one:

I.  Either the stream is invalid and it'll abort parsing;
II. Or we're using a syntactic extension to the JSON stream and want to
    trigger a fallback mini-parser to consume that part of the stream.

If a parser doesn't report invalid token the user will try to buffer the
stream forever. However if invalid token is a terminal state then the
user can't combine parsers to support an extended JSON syntax. A chunked
parser meant to be used combined with other parsers should report all 3
scenarios:

* Valid token.
* Insufficient tokens.
* Invalid token (and invalid token cannot be a terminal state).

If we exclude the first event from the notification set the parser isn't
useful at all. If we exclude the second event then we don't have a
chunked parser. If we exclude the third event the user might buffer
forever on invalid tokens. Thus all three events must be part of the
notification set.
---
 test/json/chunk_reader_suite.cpp | 54 ++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/test/json/chunk_reader_suite.cpp b/test/json/chunk_reader_suite.cpp
index 1eaf395..cfdbf4a 100644
--- a/test/json/chunk_reader_suite.cpp
+++ b/test/json/chunk_reader_suite.cpp
@@ -43,10 +43,20 @@ void string_missing_array_end()
     TRIAL_PROTOCOL_TEST_EQUAL(reader.code(), token::code::end_array);
 }
 
+void string_invalid_token()
+{
+    json::chunk_reader reader;
+    TRIAL_PROTOCOL_TEST(reader.finish("\"a\"%"));
+    TRIAL_PROTOCOL_TEST_EQUAL(reader.code(), token::code::string);
+    TRIAL_PROTOCOL_TEST(!reader.next());
+    TRIAL_PROTOCOL_TEST_EQUAL(reader.code(), token::code::error_unexpected_token);
+}
+
 void run()
 {
     string_missing_quote();
     string_missing_array_end();
+    string_invalid_token();
 }
 
 } // namespace string_suite
@@ -168,6 +178,48 @@ void run()
 
 //-----------------------------------------------------------------------------
 
+namespace array_suite
+{
+
+void array_invalid_token()
+{
+    json::chunk_reader reader;
+    TRIAL_PROTOCOL_TEST(reader.finish("[%"));
+    TRIAL_PROTOCOL_TEST_EQUAL(reader.code(), token::code::begin_array);
+    TRIAL_PROTOCOL_TEST(!reader.next());
+    TRIAL_PROTOCOL_TEST_EQUAL(reader.code(), token::code::error_unexpected_token);
+}
+
+void run()
+{
+    array_invalid_token();
+}
+
+} // namespace array_suite
+
+//-----------------------------------------------------------------------------
+
+namespace object_suite
+{
+
+void object_invalid_token()
+{
+    json::chunk_reader reader;
+    TRIAL_PROTOCOL_TEST(reader.finish("{%"));
+    TRIAL_PROTOCOL_TEST_EQUAL(reader.code(), token::code::begin_object);
+    TRIAL_PROTOCOL_TEST(!reader.next());
+    TRIAL_PROTOCOL_TEST_EQUAL(reader.code(), token::code::error_unexpected_token);
+}
+
+void run()
+{
+    object_invalid_token();
+}
+
+} // namespace object_suite
+
+//-----------------------------------------------------------------------------
+
 namespace whitespace_suite
 {
 
@@ -228,6 +280,8 @@ int main()
 {
     string_suite::run();
     number_suite::run();
+    array_suite::run();
+    object_suite::run();
     whitespace_suite::run();
 
     return boost::report_errors();