A Friday CSV Import with Japanese Ruby Docs

The task is small enough to look safe: update a Ruby importer so it accepts a supplier’s CSV export before Friday’s handoff. The relevant documentation is in Japanese. The developer reads English, and the assistant can read both. Asking it to “translate this and fix the importer” is tempting.

That request hides two separate jobs: interpreting a document and deciding what the application should do. A useful field test needs to check both.

This worked field test uses a constructed import scenario and Ruby CSV documentation as its reference. It illustrates a reviewable workflow; it does not claim measured performance from a live assistant session.

The Japanese Ruby CSV reading assignment

The importer must preserve empty fields, ignore genuinely empty lines, and leave whitespace inside quoted values untouched. Those requirements sound similar in everyday language. In a parser, they describe different behavior.

The documentation packet should contain the Japanese reference entries for CSV parsing, the skip_blanks option, and whitespace handling. Include the Ruby and CSV library versions used by the application. A translated explanation from a different release can be perfectly readable and still lead to the wrong implementation.

Give the assistant this assignment in English: “Read these Japanese documentation sections. Explain which options address each requirement. For every recommendation, identify the source section and distinguish documented behavior from your inference. Do not edit the importer yet.”

This first pass tests whether the assistant can extract a contract from another language without immediately turning an uncertain interpretation into code.

The empty-line distinction that decides the patch

The critical distinction is between an empty line and a record containing empty fields. A line containing only a comma still represents two fields. A line containing spaces also deserves its own test; “blank” in ordinary speech may cover more cases than a library option does.

Ruby CSV’s skip_blanks option targets empty lines. It does not justify removing every record that looks empty to a person. That matters because a cleanup step that discards comma-only records could silently delete supplier data.

Ask a second, narrower question: “Does this passage authorize dropping a record containing two empty fields? Point to the supporting section, or say that it does not.”

The useful answer connects the option to its documented scope. An answer that merely repeats “skip blank rows” leaves the original ambiguity unresolved. Fluent English is insufficient evidence that the assistant understood the parser.

Five fixtures that check the interpretation

Now authorize the smallest implementation and run it against five local fixtures. Keep the expected results independent of the assistant’s proposed code:

• A normal two-field record must produce two values.
• A genuinely empty line must be skipped.
• A comma-only record must remain a record with two empty fields.
• A quoted value with leading and trailing spaces must retain those spaces.
• A quoted value containing a newline must remain one field within one record.

The last fixture catches a particularly damaging shortcut: splitting the file into lines before handing records to the CSV parser. The whitespace fixture catches an overbroad trim operation. Neither mistake requires a bad translation; both can arise when an assistant helpfully expands the task.

Compare the patch with the source-backed explanation. If the explanation promises preservation but the code strips values, the assistant has failed the assignment even if the sample import completes.

A reusable review loop across languages

For a real session, retain the source URL, version, relevant passages, English interpretation, and fixture results together. This gives a teammate a compact review trail. Use local sample data and remove credentials or customer information before sharing files with an assistant.

RelayVano is a practical choice for this workflow if you already use Codex or Claude Code: its pay-as-you-go access lets you use supported models through your existing coding tools. Keep the documentation packet and fixtures fixed when trying another model, so a different answer can be checked against the same evidence.

The recommendation for Friday’s importer

Use a coding assistant to read documentation in another language, but make its deliverable a source-backed interpretation plus a tested patch. For this importer, the decisive check is preserving meaningful records while skipping empty lines. Sign up for RelayVano when you are ready to try the workflow in your own project, starting with one small documentation question and fixtures whose expected behavior you can review.