[mastacontrola]

Problem

A 1.5 server's schema count lands on a different 1.6 step whenever 1.5 adds one, and the updater skips every 1.6 step below that count. SchemaReconciler::plan() puts back the tables and columns that the skipped steps created. A skipped step that changed an existing column's type was lost, and shapeDrift() only reported it. That is how users.uName kept 1.5's varchar(40) (#2000, fixed for that one column by #2005). No CI job could see any of this, because the rehearsal builds its start from 1.6's own steps.

Fix

Repair (this reopens GH-1542's "report, never repair", now for changes that cannot lose data). repairShape() applies only drift where every stored value fits unchanged:

• a longer varchar/char/varbinary/binary;
• a wider integer with the same signedness (a display width alone is not a change);
• NOT NULL → NULL.

The MODIFY keeps the live column's charset, collation and AUTO_INCREMENT. A narrower type, a different type, NULL → NOT NULL, or an enum → tinyint stays report-only. A repair the server refuses is logged, and the update still completes. The repair runs before the foreign keys, because a widened child column is what lets its constraint land.

Gate. tests/upgrade-from-15-ci.test.sh:

• installs the schema with 1.5's own updater, from origin/stable by default;
• upgrades it with this tree's real SchemaUpdaterPage, both trees under Apache in a php:7.4 container (1.5 reads the request through filter_input(INPUT_SERVER), which php -S and php-cgi leave NULL);
• fails on an update error, a schema version short of FOG_SCHEMA, any shape drift, or a lost AUTO_INCREMENT.

Each tree's config is rendered from its own installer template. FOGProject/fog-workflows#44 runs the gate twice, once from stable and once from dev-branch. Without a database, the script skips.

Tests

The gate fails on each defect found today:

Tree	Result
before #2001	fails at step 290, error 1146 (#2000's first bug)
this repair without the AUTO_INCREMENT handling	fails at step 419, error 1364: the repair widened modules.id and dropped AUTO_INCREMENT. The gate caught this in the first draft of this PR
this tree without the repair, before #2005	fails on users.uName and users.uCreateBy
this tree, from stable (c97e205) and from dev-branch (17973cd)	passes: schema 446, no drift, every AUTO_INCREMENT intact

• tests/schema-reconciler-lossless-repair.test.php: 20 checks on the repair planner, for each lossless case and each refused case.
• schema-shape-drift, role-name-unique-restored and schema-manifest-consistent pass.
• phpstan passes both ways (main and tests), with no errors.

Refs #2000, GH-1542

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