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Function: diffSchemas()

diffSchemas(baseline, current, migrationPathExists): CheckResult

Defined in: diff.ts:113

Compares a baseline snapshot against the current save shape.

Classification follows the engine's actual load behaviour (BaseGameObject.load()), not intuition:

• a new field on an existing entity keeps its default, because loading merges the save over the freshly constructed defaults - harmless
• a new entity the save knows nothing about has its variables cleared, not defaulted - it needs a migration
• a renamed field leaves the player's value stranded under the old name
• a changed kind hands the game a value of the wrong type
• a removed passage leaves _system.game.currentPassageId dangling, and the engine resolves it to null without complaining

Parameters

baseline

SaveSchema

Schema of the released version

current

SaveSchema

Schema of the version under development

migrationPathExists

Whether the game registers a migration chain from the baseline version to the current one. Pass null when unknown, which is the case for any capture that did not import the game's code.

boolean | null

Returns

CheckResult

Findings plus whether a migration is required

Example

const result = diffSchemas(baseline, current);
if (result.migrationRequired) {
    console.error(result.findings);
}