[MISC] Refine unknown tag handling (HD/PG)

include/seqan3/io/sam_file/detail/format_sam_base.hpp

@@ -341,13 +341,17 @@ inline void format_sam_base::read_header(stream_view_type && stream_view,
         read_forward_range_field(string_buffer, value);
     };
 
-    auto print_cerr_of_unspported_tag = [&options](char const * const header_tag, std::array<char, 2> raw_tag)
+    auto consume_unsupported_tag_and_print_warning = [&](char const * const header_tag, std::array<char, 2> raw_tag)
     {
+        // Not using `copy_next_tag_value_into_buffer` because we do not care whether the tag is valid.
+        // E.g., `pb5.0.0` instead of `pb:5.0.0`, would break the parsing if we used `copy_next_tag_value_into_buffer`.
+        take_until_predicate(is_char<'\t'> || is_char<'\n'>);
+
         if (options.stream_warnings_to == nullptr)
             return;
 
-        *options.stream_warnings_to << "Unsupported SAM header tag in @" << header_tag << ": " << raw_tag[0]
-                                    << raw_tag[1] << '\n';
+        *options.stream_warnings_to << "Unsupported tag found in SAM header @" << header_tag << ": \"" << raw_tag[0]
+                                    << raw_tag[1] << string_buffer << "\"\n";
     };
 
     while (it != end && is_char<'@'>(*it))
@@ -388,7 +392,7 @@ inline void format_sam_base::read_header(stream_view_type && stream_view,
                 }
                 default: // unsupported header tag
                 {
-                    print_cerr_of_unspported_tag("HD", raw_tag);
+                    consume_unsupported_tag_and_print_warning("HD", raw_tag);
                 }
                 }
 
@@ -397,8 +401,6 @@ inline void format_sam_base::read_header(stream_view_type && stream_view,
                     copy_next_tag_value_into_buffer();
                     read_forward_range_field(string_buffer, *header_entry);
                 }
-                else
-                    skip_until_predicate(is_char<'\t'> || is_char<'\n'>);
             }
             ++it; // skip newline
 
@@ -562,7 +564,7 @@ inline void format_sam_base::read_header(stream_view_type && stream_view,
                 }
                 default: // unsupported header tag
                 {
-                    print_cerr_of_unspported_tag("PG", raw_tag);
+                    consume_unsupported_tag_and_print_warning("PG", raw_tag);
                 }
                 }
 
@@ -571,8 +573,6 @@ inline void format_sam_base::read_header(stream_view_type && stream_view,
                     copy_next_tag_value_into_buffer();
                     read_forward_range_field(string_buffer, *program_info_entry);
                 }
-                else
-                    skip_until_predicate(is_char<'\t'> || is_char<'\n'>);
             }
             ++it; // skip newline
 

test/snippet/io/sam_file/sam_file_input_options.cpp

@@ -31,7 +31,7 @@ struct temporary_file
     }
 };
 
-static constexpr auto sam_file_raw = R"(@HD	VN:1.6	pb:5.0.0
+static constexpr auto sam_file_raw = R"(@HD	VN:1.6	pb:5.0.0	ot:ter
 @SQ	SN:ref	LN:34
 )";
 
@@ -43,16 +43,14 @@ static auto get_sam_file_input()
 void defaults_to_cerr()
 {
     auto fin = get_sam_file_input();
-    std::cerr << "Written to cerr: ";
-    auto it = fin.begin(); // Prints to cerr: "Unsupported SAM header tag in @HD: pb"
+    auto it = fin.begin();
 }
 
 void redirect_to_cout()
 {
     auto fin = get_sam_file_input();
     fin.options.stream_warnings_to = std::addressof(std::cout); // Equivalent to `= &std::cout;`
-    std::cout << "Written to cout: ";
-    auto it = fin.begin(); // Prints to cout: "Unsupported SAM header tag in @HD: pb"
+    auto it = fin.begin();
 }
 
 void redirect_to_file()
@@ -63,23 +61,54 @@ void redirect_to_file()
     { // Inner scope to close file before reading
         std::ofstream warning_file{tmp_file.path};
         fin.options.stream_warnings_to = std::addressof(warning_file); // Equivalent to `= &warning_file;`
-        auto it = fin.begin(); // Prints to file: "Unsupported SAM header tag in @HD: pb"
+        auto it = fin.begin();
     }
 
-    std::cout << "Written to file: " << tmp_file.read_content();
+    std::cout << "File content:\n" << tmp_file.read_content();
 }
 
 void silence_warnings()
 {
     auto fin = get_sam_file_input();
     fin.options.stream_warnings_to = nullptr;
-    auto it = fin.begin(); // No warning emitted
+    auto it = fin.begin();
+}
+
+void filter()
+{
+    auto fin = get_sam_file_input();
+    std::stringstream stream{};
+    fin.options.stream_warnings_to = std::addressof(stream); // Equivalent to `= &stream;`
+    auto it = fin.begin();
+
+    for (std::string line{}; std::getline(stream, line);)
+    {
+        // If "pb" is not found in the warning, print it to cerr.
+        if (line.find("pb") == std::string::npos) // C++23: `!line.contains("pb")`
+            std::cerr << line << '\n';
+    }
+}
+
+void print_section(std::string_view const section)
+{
+    std::cout << "### " << section << " ###\n";
+    std::cerr << "### " << section << " ###\n";
 }
 
 int main()
 {
+    print_section("defaults_to_cerr");
     defaults_to_cerr();
+
+    print_section("redirect_to_cout");
     redirect_to_cout();
+
+    print_section("redirect_to_file");
     redirect_to_file();
+
+    print_section("silence_warnings");
     silence_warnings();
+
+    print_section("filter");
+    filter();
 }

test/snippet/io/sam_file/sam_file_input_options.err

@@ -1 +1,8 @@
-Written to cerr: Unsupported SAM header tag in @HD: pb
+### defaults_to_cerr ###
+Unsupported tag found in SAM header @HD: "pb:5.0.0"
+Unsupported tag found in SAM header @HD: "ot:ter"
+### redirect_to_cout ###
+### redirect_to_file ###
+### silence_warnings ###
+### filter ###
+Unsupported tag found in SAM header @HD: "ot:ter"

test/snippet/io/sam_file/sam_file_input_options.out

@@ -1,2 +1,10 @@
-Written to cout: Unsupported SAM header tag in @HD: pb
-Written to file: Unsupported SAM header tag in @HD: pb
+### defaults_to_cerr ###
+### redirect_to_cout ###
+Unsupported tag found in SAM header @HD: "pb:5.0.0"
+Unsupported tag found in SAM header @HD: "ot:ter"
+### redirect_to_file ###
+File content:
+Unsupported tag found in SAM header @HD: "pb:5.0.0"
+Unsupported tag found in SAM header @HD: "ot:ter"
+### silence_warnings ###
+### filter ###

test/unit/io/sam_file/format_bam_test.cpp

@@ -38,11 +38,14 @@ struct sam_file_read<seqan3::format_bam> : public sam_file_data
                                '\x72', '\x65', '\x66', '\x00', '\x22', '\x00', '\x00', '\x00'};
 
     std::string unknown_tag_header{
-        '\x42', '\x41', '\x4d', '\x01', '\x25', '\x00', '\x00', '\x00', '\x40', '\x48', '\x44', '\x09', '\x56',
+        '\x42', '\x41', '\x4d', '\x01', '\x4b', '\x00', '\x00', '\x00', '\x40', '\x48', '\x44', '\x09', '\x56',
         '\x4e', '\x3a', '\x31', '\x2e', '\x36', '\x09', '\x70', '\x62', '\x3a', '\x35', '\x2e', '\x30', '\x2e',
-        '\x30', '\x0a', '\x40', '\x53', '\x51', '\x09', '\x53', '\x4e', '\x3a', '\x72', '\x65', '\x66', '\x09',
-        '\x4c', '\x4e', '\x3a', '\x33', '\x34', '\x0a', '\x01', '\x00', '\x00', '\x00', '\x04', '\x00', '\x00',
-        '\x00', '\x72', '\x65', '\x66', '\x00', '\x22', '\x00', '\x00', '\x00'};
+        '\x30', '\x09', '\x6f', '\x74', '\x74', '\x65', '\x72', '\x0a', '\x40', '\x53', '\x51', '\x09', '\x53',
+        '\x4e', '\x3a', '\x72', '\x65', '\x66', '\x09', '\x4c', '\x4e', '\x3a', '\x33', '\x34', '\x0a', '\x40',
+        '\x50', '\x47', '\x09', '\x49', '\x44', '\x3a', '\x6e', '\x6f', '\x76', '\x6f', '\x61', '\x6c', '\x69',
+        '\x67', '\x6e', '\x09', '\x70', '\x62', '\x3a', '\x35', '\x2e', '\x30', '\x2e', '\x30', '\x09', '\x6f',
+        '\x74', '\x74', '\x65', '\x72', '\x0a', '\x01', '\x00', '\x00', '\x00', '\x04', '\x00', '\x00', '\x00',
+        '\x72', '\x65', '\x66', '\x00', '\x22', '\x00', '\x00', '\x00'};
 
     std::string big_header_input{
         '\x42', '\x41', '\x4D', '\x01', '\xB7', '\x01', '\x00', '\x00', '\x40', '\x48', '\x44', '\x09', '\x56', '\x4E',

test/unit/io/sam_file/format_sam_test.cpp

@@ -20,9 +20,12 @@ struct sam_file_read<seqan3::format_sam> : public sam_file_data
 @SQ	SN:ref	LN:34
 )"};
 
+    // "otter" is not valid because a user-defined/local tag must have the format [TAG]:[VALUE].
+    // However, encountering such a tag should not break the parsing.
     std::string unknown_tag_header{
-        R"(@HD	VN:1.6	pb:5.0.0
+        R"(@HD	VN:1.6	pb:5.0.0	otter
 @SQ	SN:ref	LN:34
+@PG	ID:novoalign	pb:5.0.0	otter
 )"};
 
     std::string big_header_input{
@@ -176,16 +179,17 @@ TEST_F(sam_format, header_errors)
             "@SQ\tSN:ref2\tLN:243199373\tSB:user_tag\tLB:user_tag\tpb:user_tag\n"
             "@RG\tID:U0a_A2_L1\tIB:user_tag\tpb:user_tag\n"
             "@PG\tID:qc\tIB:user_tag\tPB:user_tag\tCB:user_tag\tDB:user_tag\tVB:user_tag\tpb:user_tag\n"};
-        std::string expected_cerr{"Unsupported SAM header tag in @HD: VB\n"
-                                  "Unsupported SAM header tag in @HD: SB\n"
-                                  "Unsupported SAM header tag in @HD: GB\n"
-                                  "Unsupported SAM header tag in @HD: pb\n"
-                                  "Unsupported SAM header tag in @PG: IB\n"
-                                  "Unsupported SAM header tag in @PG: PB\n"
-                                  "Unsupported SAM header tag in @PG: CB\n"
-                                  "Unsupported SAM header tag in @PG: DB\n"
-                                  "Unsupported SAM header tag in @PG: VB\n"
-                                  "Unsupported SAM header tag in @PG: pb\n"};
+        std::string expected_cerr{"Unsupported tag found in SAM header @HD: \"VB:user_tag\"\n"
+                                  "Unsupported tag found in SAM header @HD: \"SB:user_tag\"\n"
+                                  "Unsupported tag found in SAM header @HD: \"GB:user_tag\"\n"
+                                  "Unsupported tag found in SAM header @HD: \"pb:user_tag\"\n"
+                                  "Unsupported tag found in SAM header @PG: \"IB:user_tag\"\n"
+                                  "Unsupported tag found in SAM header @PG: \"PB:user_tag\"\n"
+                                  "Unsupported tag found in SAM header @PG: \"CB:user_tag\"\n"
+                                  "Unsupported tag found in SAM header @PG: \"DB:user_tag\"\n"
+                                  "Unsupported tag found in SAM header @PG: \"VB:user_tag\"\n"
+                                  "Unsupported tag found in SAM header @PG: \"pb:user_tag\"\n"};
+
         std::istringstream istream(header_str);
         seqan3::sam_file_input fin{istream, seqan3::format_sam{}};
 

test/unit/io/sam_file/sam_file_format_test_template.hpp

@@ -359,6 +359,10 @@ TYPED_TEST_P(sam_file_read, issue2423)
 
 TYPED_TEST_P(sam_file_read, unknown_header_tag)
 {
+    constexpr std::string_view expected_warning = "Unsupported tag found in SAM header @HD: \"pb:5.0.0\"\n"
+                                                  "Unsupported tag found in SAM header @HD: \"otter\"\n"
+                                                  "Unsupported tag found in SAM header @PG: \"pb:5.0.0\"\n"
+                                                  "Unsupported tag found in SAM header @PG: \"otter\"\n";
     // Default: Warnings to cerr
     {
         typename TestFixture::stream_type istream{this->unknown_tag_header};
@@ -367,7 +371,7 @@ TYPED_TEST_P(sam_file_read, unknown_header_tag)
         testing::internal::CaptureStderr();
         EXPECT_NO_THROW(fin.begin());
         EXPECT_EQ(testing::internal::GetCapturedStdout(), "");
-        EXPECT_EQ(testing::internal::GetCapturedStderr(), "Unsupported SAM header tag in @HD: pb\n");
+        EXPECT_EQ(testing::internal::GetCapturedStderr(), expected_warning);
     }
     // Redirect to cout
     {
@@ -377,7 +381,7 @@ TYPED_TEST_P(sam_file_read, unknown_header_tag)
         testing::internal::CaptureStdout();
         testing::internal::CaptureStderr();
         EXPECT_NO_THROW(fin.begin());
-        EXPECT_EQ(testing::internal::GetCapturedStdout(), "Unsupported SAM header tag in @HD: pb\n");
+        EXPECT_EQ(testing::internal::GetCapturedStdout(), expected_warning);
         EXPECT_EQ(testing::internal::GetCapturedStderr(), "");
     }
     // Redirect to file
@@ -403,7 +407,7 @@ TYPED_TEST_P(sam_file_read, unknown_header_tag)
         std::ifstream warning_file{filename};
         ASSERT_TRUE(warning_file.good());
         std::string content{std::istreambuf_iterator<char>(warning_file), std::istreambuf_iterator<char>()};
-        EXPECT_EQ(content, "Unsupported SAM header tag in @HD: pb\n");
+        EXPECT_EQ(content, expected_warning);
     }
     // Silence
     {