Drupal Release: 7.0-rc-2

TL;DR

Drupal 7.0-rc2 is the second release candidate for Drupal 7.0, focusing primarily on bug fixes, documentation improvements, and UI enhancements. This release addresses critical issues found in RC1, including PDO exceptions during upgrades, form handling problems, and various UI styling issues in the Bartik theme. It also improves documentation across multiple areas of the codebase and fixes several accessibility and usability concerns.

Highlight of the Release

• Added README.txt to core providing general information about Drupal and reference links
• Fixed critical PDO exceptions when upgrading from Drupal 6.19 to Drupal 7 RC1
• Improved form handling with fixes for #states on submit buttons and AJAX bindings in IE
• Enhanced Bartik theme with multiple styling fixes for comments, disabled elements, and more
• Performance improvements to the t() function for better translation handling

Migration Guide

This is a release candidate, not a final release, so no formal migration guide is provided. However, users upgrading from Drupal 6.x to Drupal 7.0-rc2 should note:

1. The issue that caused PDO exceptions when upgrading from Drupal 6.19 to Drupal 7 RC1 has been fixed (#991046)
2. The issue where sites were incorrectly taken out of maintenance mode during upgrades has been resolved (#984358)
3. The update module now better verifies downloaded tarballs and propagates errors correctly (#936490)

If you're upgrading from Drupal 7.0-rc1 to 7.0-rc2, the process should be straightforward as this release primarily contains bug fixes and documentation improvements.

Upgrade Recommendations

For Drupal 6.x Users

If you were waiting to upgrade from Drupal 6.x to Drupal 7 due to the PDO exceptions in RC1, this release candidate addresses those critical issues. However, as this is still a release candidate, it's recommended to test thoroughly in a staging environment before upgrading production sites.

For Drupal 7.0-rc1 Users

It is strongly recommended to upgrade to Drupal 7.0-rc2 as it fixes several critical issues found in RC1, including PDO exceptions, form handling problems, and upgrade path issues. The changes are primarily bug fixes and should not introduce new compatibility issues.

For All Users

As this is a release candidate, it's still advisable to:

1. Back up your database and files before upgrading
2. Test the upgrade on a staging/development environment first
3. Review the full list of changes to identify any that might affect your specific site configuration

Bug Fixes

Core System

• Fixed PDO exception when upgrading from Drupal 6.19 to Drupal 7 RC1 (#991046)
• Fixed regression in load_functions detection for menu items (#979958)
• Fixed issue where sites were incorrectly taken out of maintenance mode during upgrades (#984358)
• Fixed PDO exception when attempting to add a new not null field with initial value (#973314)
• Fixed nodes published before 1970 not inserting in taxonomy index (#985292)
• Fixed private file download returning access denied (#992674)
• Fixed issue where messages were generated too early (#982814)

Forms and AJAX

• Fixed AJAX bindings not working on checkbox or radio buttons in IE6/7/8 (#557284)
• Fixed #states not working on submit buttons (#984416)
• Fixed form action URL not being obtained properly in SimpleTest (#947820)
• Fixed theme_container not working with non-form elements (#988760)

Search and Comments

• Fixed language selection in advanced search filters (#950460)
• Fixed 'Add new comment' text appearing in search result snippets (#903392)
• Fixed comment publish/unpublish actions (#974072)
• Fixed search from block with no keywords not displaying the 'Please enter some keywords' message (#518512)

UI and Theming

• Fixed styling for sticky content (#862854)
• Fixed styling for disabled form elements in Bartik (#854432)
• Fixed styling issues with taxonomy term displays in Bartik (#819996)
• Fixed styling issues with unpublished comments (#928776)
• Fixed duplicate IDs in preview.html in Bartik (#988184)
• Fixed styling for Bartik Highlight and Help regions (#827530)
• Added background for messages when featured is active in Bartik (#929780)
• Fixed styling for PRE and CODE tags in Bartik (#827528)

Other

• Fixed clearing the log with a filter throwing notice and PDO Exception (#978050)
• Fixed update module not verifying downloaded tarballs correctly (#936490)
• Fixed overlay behavior on phpinfo() link (#941288)
• Fixed image_get_info() failing on IIS on new uploads (#307636)
• Fixed 'Your name' being prepopulated with 'Anonymous' (#632382)

New Features

• Core README.txt: Added a README.txt file to Drupal core that provides general information about Drupal and pointers to important reference pages (#607028)
• Enhanced Context for Field Hooks: Added context parameter to hook_field_attach_view_alter() to provide more information to implementing modules (#990148)
• Improved Token Support: The [current-user:?] token now provides the actual loaded user object rather than just basic information (#967330)

Security Updates

No specific security fixes were mentioned in this release. However, the fix for private file downloads returning access denied (#992674) does have security implications by ensuring proper access control for private files.

Performance Improvements

• Faster Translation Function: Optimized the t() function to improve performance across the entire system (#991588)
• Improved File Handling: Enhanced private file download handling for better performance and security (#992674)
• More Efficient Message Handling: Fixed issue where messages were generated too early, improving page rendering efficiency (#982814)

Impact Summary

Drupal 7.0-rc2 represents a significant step toward a stable Drupal 7.0 release by addressing critical issues found in RC1. The most impactful changes include fixing PDO exceptions during upgrades from Drupal 6.x, resolving issues with form handling and AJAX in Internet Explorer, and improving the Bartik theme's styling across various elements.

For developers, the improved documentation and API clarifications will make development more straightforward, while site administrators will benefit from the fixed upgrade path and better error handling. Content editors will appreciate the fixes to comment management and taxonomy term displays.

This release candidate demonstrates Drupal's commitment to accessibility, usability, and backward compatibility, with numerous fixes targeting these areas. The performance improvements to core functions like t() also indicate ongoing efforts to optimize Drupal 7's performance.

While this is still a release candidate and not recommended for production sites without thorough testing, it addresses many of the critical issues that were blocking adoption of Drupal 7 and represents a much more stable platform than RC1.