test(terminal): cover reveal repaint and pruned diagnostics

src/renderer/src/lib/pane-manager/pane-rendering-diagnostics.ts

@@ -1,5 +1,6 @@
 import type { ManagedPaneInternal, PaneRenderingDiagnostics } from './pane-manager-types'
 import { getTerminalWebglAutoDecision } from './terminal-webgl-auto-policy'
+import { prunePaneWebglContextLosses } from './pane-webgl-context-loss-policy'
 
 export function collectPaneRenderingDiagnostics(
   panes: Map<number, ManagedPaneInternal>
@@ -10,7 +11,7 @@ export function collectPaneRenderingDiagnostics(
     gpuRenderingEnabled: pane.gpuRenderingEnabled,
     webglAttachmentDeferred: pane.webglAttachmentDeferred,
     webglDisabledAfterContextLoss: pane.webglDisabledAfterContextLoss,
-    webglContextLossesInWindow: pane.webglContextLossTimestamps?.length ?? 0,
+    webglContextLossesInWindow: prunePaneWebglContextLosses(pane),
     webglAttachFailedSinceRecovery: pane.webglAttachFailedSinceRecovery === true,
     hasComplexScriptOutput: pane.hasComplexScriptOutput,
     terminalWebglAutoDecision: getTerminalWebglAutoDecision(),

src/renderer/src/lib/pane-manager/pane-reveal-repaint.test.ts

@@ -239,6 +239,7 @@ describe('schedulePaneRevealRepaint', () => {
     it('reattaches a pane that lost WebGL while hidden when its tab is revealed', () => {
       const pane = createPane()
       pane.webglDisabledAfterContextLoss = true
+      pane.webglContextLossTimestamps = [Date.now()]
 
       schedulePaneRevealPresent(() => [pane])
       flushFrame()
@@ -246,6 +247,8 @@ describe('schedulePaneRevealRepaint', () => {
 
       expect(pane.webglDisabledAfterContextLoss).toBe(false)
       expect(pane.webglAddon).not.toBeNull()
+      expect(pane.terminal.refresh).toHaveBeenCalledTimes(2)
+      expect(pane.terminal.refresh).toHaveBeenNthCalledWith(2, 0, 23)
     })
   })
 })

src/renderer/src/lib/pane-manager/pane-webgl-context-loss-policy.ts

@@ -9,6 +9,12 @@ function recentContextLosses(pane: ManagedPaneInternal, now: number): number[] {
   return (pane.webglContextLossTimestamps ?? []).filter((timestamp) => timestamp > cutoff)
 }
 
+export function prunePaneWebglContextLosses(pane: ManagedPaneInternal, now = Date.now()): number {
+  const losses = recentContextLosses(pane, now)
+  pane.webglContextLossTimestamps = losses
+  return losses.length
+}
+
 export function recordPaneWebglContextLoss(pane: ManagedPaneInternal, now = Date.now()): number {
   const losses = recentContextLosses(pane, now)
   losses.push(now)
@@ -20,9 +26,7 @@ export function canRetryPaneWebglAfterContextLoss(
   pane: ManagedPaneInternal,
   now = Date.now()
 ): boolean {
-  const losses = recentContextLosses(pane, now)
-  pane.webglContextLossTimestamps = losses
-  return losses.length < WEBGL_CONTEXT_LOSS_RETRY_LIMIT
+  return prunePaneWebglContextLosses(pane, now) < WEBGL_CONTEXT_LOSS_RETRY_LIMIT
 }
 
 export function resetPaneWebglContextLosses(pane: ManagedPaneInternal): void {

src/renderer/src/lib/pane-manager/pane-webgl-context-recovery.test.ts

@@ -2,6 +2,7 @@ import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import { setTerminalWebglDiagnosticRecorder } from '../../../../shared/terminal-webgl-diagnostics'
 import type { ManagedPaneInternal } from './pane-manager-types'
 import { resumePaneRendering, suspendPaneRendering } from './pane-rendering-control'
+import { collectPaneRenderingDiagnostics } from './pane-rendering-diagnostics'
 import { attachWebgl, resetTerminalWebglSuggestion } from './pane-webgl-renderer'
 import { rebuildAttachedWebgl } from './pane-webgl-reattach'
 
@@ -216,4 +217,16 @@ describe('terminal WebGL context recovery', () => {
       }
     ])
   })
+
+  it('reports only recent context losses in rendering diagnostics', () => {
+    const now = 1_700_000_000_000
+    vi.spyOn(Date, 'now').mockReturnValue(now)
+    const pane = createPane()
+    pane.webglContextLossTimestamps = [now - 60_001, now - 1_000]
+
+    const [diagnostics] = collectPaneRenderingDiagnostics(new Map([[pane.id, pane]]))
+
+    expect(diagnostics.webglContextLossesInWindow).toBe(1)
+    expect(pane.webglContextLossTimestamps).toEqual([now - 1_000])
+  })
 })