Prepend emails to top of document instead of appending to bottom

[Copilot]

• Update README.md specifications to document prepend behavior
• Add test for prepending behavior in document
• Modify code.gs to prepend content instead of append
• Update mocks to support insertParagraph
• Create comprehensive integration test
• Run full test suite (all tests pass)
• Code review (addressed clarification needs)
• Security check (no issues found)
• Add clarifying comments to code
• Fix message ordering to be explicit (sort by date)
• Remove unused imports and variables
• Add bounds checking to insertParagraph mock
• Extract testable processing functions to src/index.js
• Refactor integration tests to use real functions
• Add copyBlob() support to mocks
• Add deduplication test using production logic
• Add clarifying comments for blob handling
• Add comprehensive tests for 100% line coverage

Original prompt

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This section details on the original issue you should resolve

<issue_title>gmail-to-drive adds new content to the bottom rather than top of document</issue_title>
<issue_description>When gmail-to-drive runs, it is appending the email content to the document rather than pre-pending. This forces the consumer of this content to scroll to the bottom of the document for the most recent and relevant content.

• Add rule to specifications, tests and implementation that newer content should be added to the top of the document (prepended)</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes gmail-to-drive-by-labels adds new content to the bottom rather than top of document #22

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[Copilot]

Pull request overview

Updates gmail-to-drive-by-labels so newly processed email content is inserted at the top of the target Google Doc, aiming to make the most recent content visible without scrolling.

Changes:

• Switches document writes from appendParagraph(...) to insertParagraph(0/idx, ...) to prepend each email block.
• Extends the DocumentApp test mock with insertParagraph(childIndex, text) support.
• Adds new Jest tests intended to validate newest-first ordering and attachment listing with prepend behavior, and updates README wording.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
src/gmail-to-drive-by-labels/code.gs	Changes message rendering to use insertParagraph with a per-message index to prepend content.
test-utils/mocks.js	Adds insertParagraph support to the Document body mock for tests.
src/gmail-to-drive-by-labels/tests/prepend-behavior.test.js	Adds unit-style tests around paragraph ordering when inserting at the top.
src/gmail-to-drive-by-labels/tests/integration.test.js	Adds integration-style tests simulating the email processing flow with prepend behavior.
src/gmail-to-drive-by-labels/README.md	Updates documentation to reflect prepend/newest-first behavior.

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[don-petry]

@copilot - Code coverage test is failing. Add more tests until it passes.

[Copilot]

@copilot - Code coverage test is failing. Add more tests until it passes.

Fixed in commit e1098e4. Added 9 new comprehensive tests covering all previously uncovered code paths including:

• Attachment name conflicts with timestamp renaming
• File size and hash mismatch scenarios
• Files without extensions
• Logger, DocumentApp, Utilities, and Session option handling
• DocumentApp setHeading fallback behavior
• Duplicate detection with Logger

All coverage requirements now met:

• Statements: 99.74% (required: 95%)
• Branches: 90.70% (required: 85%)
• Functions: 97.37% (required: 95%)
• Lines: 100% (required: 100%)