fix(app): more defensive session context metrics

adamdotdevin · adamdotdevin · commit ed472d8a6789 · 2026-02-12T10:00:58.000-06:00
diff --git a/packages/app/src/components/session/session-context-metrics.test.ts b/packages/app/src/components/session/session-context-metrics.test.ts
@@ -91,4 +91,11 @@ describe("getSessionContextMetrics", () => {
     expect(two.context?.message.id).toBe("a2")
     expect(two.totalCost).toBe(1)
   })
+
+  test("returns empty metrics when inputs are undefined", () => {
+    const metrics = getSessionContextMetrics(undefined, undefined)
+
+    expect(metrics.totalCost).toBe(0)
+    expect(metrics.context).toBeUndefined()
+  })
 })
diff --git a/packages/app/src/components/session/session-context-metrics.ts b/packages/app/src/components/session/session-context-metrics.ts
@@ -47,7 +47,7 @@ const lastAssistantWithTokens = (messages: Message[]) => {
   }
 }
 
-const build = (messages: Message[], providers: Provider[]): Metrics => {
+const build = (messages: Message[] = [], providers: Provider[] = []): Metrics => {
   const totalCost = messages.reduce((sum, msg) => sum + (msg.role === "assistant" ? msg.cost : 0), 0)
   const message = lastAssistantWithTokens(messages)
   if (!message) return { totalCost, context: undefined }
@@ -77,6 +77,6 @@ const build = (messages: Message[], providers: Provider[]): Metrics => {
   }
 }
 
-export function getSessionContextMetrics(messages: Message[], providers: Provider[]) {
+export function getSessionContextMetrics(messages: Message[] = [], providers: Provider[] = []) {
   return build(messages, providers)
 }

Original file line number	Diff line number	Diff line change
`@@ -47,7 +47,7 @@ const lastAssistantWithTokens = (messages: Message[]) => {`
`47`	`47`	`}`
`48`	`48`	`}`
`49`	`49`
`50`		`-const build = (messages: Message[], providers: Provider[]): Metrics => {`
	`50`	`+const build = (messages: Message[] = [], providers: Provider[] = []): Metrics => {`
`51`	`51`	`const totalCost = messages.reduce((sum, msg) => sum + (msg.role === "assistant" ? msg.cost : 0), 0)`
`52`	`52`	`const message = lastAssistantWithTokens(messages)`
`53`	`53`	`if (!message) return { totalCost, context: undefined }`
`@@ -77,6 +77,6 @@ const build = (messages: Message[], providers: Provider[]): Metrics => {`
`77`	`77`	`}`
`78`	`78`	`}`
`79`	`79`
`80`		`-export function getSessionContextMetrics(messages: Message[], providers: Provider[]) {`
	`80`	`+export function getSessionContextMetrics(messages: Message[] = [], providers: Provider[] = []) {`
`81`	`81`	`return build(messages, providers)`
`82`	`82`	`}`