ProjectEngine v1.2.7 — Zero-Dependency Stability Hotfix #13

ProjectEngine v1.2.7 is a focused stability hotfix for valid schedules containing no predecessors.

This release does not introduce new scheduling features. It fixes two edge cases reported during real-world testing of v1.2.6.

Fixed

Gantt rendering with zero dependencies

A valid schedule containing no dependency links could be misinterpreted by the Gantt dependency renderer as having no dependency model at all.

This prevented the dependency renderer from reaching its normal READY state and could lead to refresh failures or misleading diagnostic behavior.

The renderer now correctly recognizes an initialized dependency model containing zero links.

Empty tbl_LOGIC_LINKS

Forced Planning Update and Full Update could fail when tbl_LOGIC_LINKS contained no data rows.

In that state, Excel can legitimately return:

tbl.DataBodyRange Is Nothing

The previous writer logic assumed that a data range was always available when rebuilding the table.

RewriteLogicLinksTable now handles the empty-table lifecycle correctly, including:

• zero links;
• first link creation;
• returning from one link to zero links;
• adding links again after an empty state;
• multiple links;
• Forced Planning Update;
• Full Update.

The writer still uses bulk operations and does not introduce row-by-row COM writes.

Validation

The hotfix was validated against:

• schedules with zero dependencies;
• normal schedules containing dependencies;
• repeated refresh/reset cycles;
• save/reopen;
• compilation;
• Gantt dependency lifecycle;
• cache/no-op paths;
• a 1,200-task performance test;
• Classic, 1200-task and Analytics workbook variants.

No scheduling-result regression was observed in the validated scenarios.

Scope

This is an isolated hotfix based on the v1.2.6 release line.

It does not include unrelated work currently under development and does not introduce any workbook schema or persistent-structure change.

Thanks

Special thanks to u/dork_souls for reporting both zero-dependency edge cases and for providing unusually detailed debugging information.

This kind of real-world testing is extremely valuable and directly helps improve ProjectEngine.