Unclosed quote is auto-closed at the end of file by the parser?

[dmitry-workato]

Hey, could someone check if this is expected behaviour:

This code:

import de.siegmar.fastcsv.reader.CsvReader;
import de.siegmar.fastcsv.reader.StringArrayHandler;

String csv = """
                col1,col2
                "val1,val2
                val3,val4
                """;
        var reader = CsvReader.builder()
                .fieldSeparator(',')
                .quoteCharacter('"')
                .skipEmptyLines(true)
                .allowExtraFields(true)
                .allowMissingFields(true)
                .allowExtraCharsAfterClosingQuote(false)
                .trimWhitespacesAroundQuotes(true)
                .maxBufferSize(1024).build(StringArrayHandler.of(), asStream(csv), StandardCharsets.UTF_8);
        Iterator<String[]> it = reader.stream().iterator();
        while (it.hasNext()) {
            String[] row = it.next();
            System.out.println("Line: " + String.join(",", row));
        }

Current Behavior

Outputs:

Line: col1,col2
Line: val1,val2
val3,val4

The unclosed quote makes parser consume all bytes till the end of the file as one column value ...

Expected Behavior

I would expect parser fail on the unclosed quote.

Steps to Reproduce

Run the java snippet

Additional Context

• Operating system: macOS
• FastCSV version: 4.1.0
• Java version: 25

Many thanks in advance for any help!

[osiegmar]

This is actually expected behavior and part of FastCSV's design to support reading non-compliant (real-world) data, as described on fastcsv.org.

When the parser encounters an opening quote but reaches end-of-data without finding a closing quote, it materializes everything read so far as the last field rather than throwing an error. This is intentional — real-world CSV files are often malformed, and failing hard on unclosed quotes would prevent processing otherwise usable data.

Out of curiosity — what's your concrete use case? What would you gain from the parser failing on an unclosed quote rather than producing a result?