fix(gmail): match message headers case-insensitively (#642)

[lucaspretti]

Re-submission of #841, which was auto-closed by the stale bot before a maintainer could review it. Same diff, head branch unchanged; CLA already signed and Gemini review was green.

Summary

gws gmail +reply-all silently drops Cc recipients when the original message's Cc header arrives with non-canonical casing (e.g. CC), which is common with Microsoft Exchange / Outlook. The original To recipients survive but the entire Cc list is lost, so a reply-all can go out missing people from the thread with no error.

Root cause

parse_message_headers (crates/google-workspace-cli/src/helpers/gmail/mod.rs) matched header names with an exact, case-sensitive match. Per RFC 5322 §1.2.2 header field names are case-insensitive, and the Gmail API preserves the original casing from the sending MTA, so CC (and any other non-canonical casing) fell through to _ => {} and was silently dropped.

Fix

Match on the lowercased header name so all casings are recognized. This also folds the previous "Message-ID" | "Message-Id" special-case into a single "message-id" arm.

Test

Adds test_parse_original_message_case_insensitive_headers, which feeds Exchange-style casing (FROM, TO, CC, cc, message-id) and asserts every recipient and the message id are parsed (i.e. Cc is not dropped).

Fixes #642

[changeset-bot]

🦋 Changeset detected

Latest commit: 68e85e5

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@googleworkspace/cli	Patch

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses an issue where the Gmail integration would silently drop 'Cc' recipients when headers arrived with non-canonical casing. By aligning the parsing logic with RFC 5322, the system now correctly handles various header casing formats, preventing data loss during 'reply-all' operations.

Highlights

• Case-Insensitive Header Parsing: Updated the Gmail message header parsing logic to use case-insensitive matching, ensuring headers like 'CC' from Microsoft Exchange/Outlook are correctly processed.
• Consolidated Header Logic: Simplified the header matching logic by folding variations of 'Message-ID' into a single case-insensitive arm.
• Regression Testing: Added a new test case to verify that non-canonical header casing is correctly parsed and that recipients are not silently dropped.

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[lucaspretti]

Re-opening this here after #841 was auto-closed by the stale bot before a maintainer could look at it.

The change is small and self-contained: header-name matching in parse_message_headers is made case-insensitive per RFC 5322 §1.2.2, which fixes +reply-all silently dropping Cc recipients when the upstream MTA (commonly Exchange/Outlook) sends the header as CC. It ships a regression test and a changeset, the CLA is signed, and the previous checks were green.

Would a maintainer be able to take a look when there is a chance? Happy to rebase or adjust anything if needed. Thanks!

[gemini-code-assist]

Code Review

This pull request updates the Gmail message header parsing logic to be case-insensitive, in compliance with RFC 5322 §1.2.2. By converting header names to lowercase before matching, it prevents headers with non-canonical casing (such as 'CC' or 'FROM' from Microsoft Exchange/Outlook) from being silently dropped. A comprehensive unit test has been added to verify this behavior. There are no review comments, so I have no additional feedback to provide.

[github-actions]

This PR has been inactive for 72 hours. Closing to keep the queue clean.

[github-actions]

This PR was closed because it has been stalled for 72 hours. Feel free to magically reopen it if you want to continue working on it!