fix(client): guard notification wiring against non-function prototype props#19
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kauandotnet merged 1 commit intomainfrom Apr 23, 2026
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… props
McpClientBootstrap.wireNotificationHandlers iterates each provider's
prototype own-property names and calls Reflect.getMetadata with the
value at each key. When any provider in the DI graph has a prototype
whose own-property list includes a non-function (e.g. plain-object
providers registered via useValue where the prototype is
Object.prototype and Object.prototype.__proto__ resolves to null, or
library classes with accessor properties returning primitives),
Reflect.getMetadata throws TypeError because its target must be an
object. This blocked any app combining McpClientModule with common
useValue: {} config providers.
Skip prototype entries whose value is not a function before looking up
metadata.
Fixes #18
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Summary
McpClientBootstrap.wireNotificationHandlersthrowingTypeErrorwhen any provider in the DI graph has a prototype whosegetOwnPropertyNameslist includes a non-function value (e.g.useValue: {}providers, whose prototype isObject.prototypeandObject.prototype.__proto__resolves tonull).typeof method !== 'function'guard before theReflect.getMetadatacall, hoistingprototype[methodName]into a local.nulland a primitive data property, asserting bootstrap resolves and the real handler still wires.Test plan
cd packages/client && pnpm test— 202/202 pass (new test + 201 existing)TypeErroratReflect.js:367fromwireNotificationHandlersbefore the guard is applied