json-schema: key bundled $defs entries by explicit @id to prevent silent overwrite

[Copilot]

In bundleId mode, schemas with the same declaration name could still collide in $defs even after @@id assigned distinct identities. This suppressed duplicate-id diagnostics while still dropping one type due to name-based $defs keying.

• Root cause

  • Bundled $defs keys were derived from declaration names (decl.name), not explicit @id values.
  • With duplicate names across namespaces, one entry overwrote the other in the bundle.

• Emitter behavior change

  • Track explicit @id per emitted declaration.
  • Use explicit @id as the $defs key when present.
  • Preserve existing fallback behavior (decl.name) for declarations without explicit @id.

• Regression coverage

  • Added a focused test for two @jsonSchema namespaces each declaring Equals, then assigning:
    • @@id(StringExpressions.Equals, "StringEquals")
    • @@id(IntegerExpressions.Equals, "IntegerEquals")
  • Assert both schemas are present in $defs under distinct keys.
  • Updated existing bundle+baseUri explicit-id assertion to validate the new keying behavior.

@jsonSchema
namespace StringExpressions { model Equals { equals: string; } }

@jsonSchema
namespace IntegerExpressions { model Equals { equals: integer; } }

@@id(StringExpressions.Equals, "StringEquals");
@@id(IntegerExpressions.Equals, "IntegerEquals");

// bundleId output now contains:
// $defs.StringEquals and $defs.IntegerEquals

• Fixes [Bug]: Title: @@id augment in bundleId mode silently resolves duplicate-id error but still drops types — $defs key should use @id value #10421

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[timotheeguerin]

@copilot fix comments

[Copilot]

@copilot fix comments

Addressed in c376066.

• Updated the changelog sentence formatting.
• Simplified the regression test to use direct @id(...) decorators (no augment decorators), while keeping the same $defs-key behavior assertions.

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/@typespec/json-schema@11505

commit: 5f8c944

[azure-sdk-automation]

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