fix(paths): a tab showing many folders no longer repaints forever (core 0.40.9)

core/package.json

@@ -1,6 +1,6 @@
 {
   "name": "prism-term-core",
-  "version": "0.40.8",
+  "version": "0.40.9",
   "description": "What Prism Terminal and Prism share: the terminal (pty, shells, agent detection and indicator, themes, links, the panel, dictation) and the update chip with its window. TypeScript source, compiled by the host.",
   "license": "MIT",
   "private": true,

core/renderer/lib/termPathLinks.test.ts

@@ -236,3 +236,35 @@ describe('the folder the tab is in is never a link found from a shown folder', (
     expect(findPath('A', CWD, 'Github-loftspace/Stutter')).toBe(null)
   })
 })
+
+// 2026-10-16: every Claude tab in the owner's Stable copy stopped taking keys
+// and scrolls, the page process at 15.9 GB and growing. A tab showing five or
+// more folders taught one that had been pushed out of the four kept on every
+// paint, and each teaching woke the tab to paint again: forever.
+describe('a tab showing many folders settles', () => {
+  afterEach(() => {
+    resetPathCache()
+    resetTermCore()
+    vi.useRealTimers()
+  })
+
+  it('wakes once per folder, then stops, however many folders it shows', async () => {
+    vi.useFakeTimers()
+    const ask = vi.fn(async (_cwd: string, texts: string[]) => texts.map((t) => ({ kind: 'file' as const, abs: t })))
+    configureTermCore({ api: { termPathKinds: ask } as unknown as TermApi } as TermHostConfig)
+    const lines = Array.from({ length: 9 }, (_, n) => `see C:\\d${n}\\f.txt and rel\\x.txt`)
+    let wakes = 0
+    // The painter: a wake repaints every line, as links.revisit() does.
+    onPathsFound('A', () => {
+      wakes += 1
+      if (wakes < 1000) lines.forEach((l) => linkRanges(l, 'C:\\cwd', 'A'))
+    })
+    lines.forEach((l) => linkRanges(l, 'C:\\cwd', 'A'))
+    for (let i = 0; i < 100; i += 1) await vi.advanceTimersByTimeAsync(50)
+    const settled = wakes
+    for (let i = 0; i < 100; i += 1) await vi.advanceTimersByTimeAsync(50)
+    expect(wakes).toBe(settled)
+    // One for the answer, one per folder taught: never more.
+    expect(wakes).toBeLessThanOrEqual(1 + lines.length)
+  })
+})

core/renderer/lib/termPathLinks.ts

@@ -65,6 +65,19 @@ const asked = new Set<string>()
 const ANCHORS_MAX = 4
 const ANCESTORS = 4
 const anchors = new Map<string, string[]>()
+/**
+ * The folders each tab has EVER been taught, for the wake below: a folder
+ * wakes its tab once, the first time, never again (2026-10-16, the owner's
+ * Stable copy: every Claude tab stopped taking keys or scrolling, the page
+ * process at 15.9 GB and growing 2.5 MB/s on 1.5 cores of CPU). The wake used
+ * to fire whenever a folder was not in the four kept, and a tab showing five
+ * or more folders pushed one out on every paint, so each repaint taught an
+ * evicted folder again, woke the tab, and repainted: 2,496 repaints in five
+ * seconds in the unit test, forever. Capped, so a tab that shows hundreds of
+ * folders stops waking rather than growing the set without end.
+ */
+const taught = new Map<string, Set<string>>()
+const TAUGHT_MAX = 256
 
 const isRelative = (p: string): boolean => !/^(?:[A-Za-z]:|[\\/]|~)/.test(p)
 const hasSeparator = (p: string): boolean => /[\\/]/.test(p)
@@ -97,11 +110,14 @@ function learnAnchor(owner: string, hit: PathHit): void {
   if (!dir) return
   const list = anchors.get(owner) ?? []
   if (list[0] === dir) return
-  const next = [dir, ...list.filter((d) => d !== dir)].slice(0, ANCHORS_MAX)
-  anchors.set(owner, next)
+  anchors.set(owner, [dir, ...list.filter((d) => d !== dir)].slice(0, ANCHORS_MAX))
   // A relative path already painted plain may name something from here: the
-  // tab looks again, once per new folder, after this paint.
-  if (!list.includes(dir)) setTimeout(() => listeners.get(owner)?.forEach((fn) => fn()), 0)
+  // tab looks again after this paint, ONCE per folder in its life (`taught`).
+  let seen = taught.get(owner)
+  if (!seen) taught.set(owner, (seen = new Set()))
+  if (seen.has(dir) || seen.size >= TAUGHT_MAX) return
+  seen.add(dir)
+  setTimeout(() => listeners.get(owner)?.forEach((fn) => fn()), 0)
 }
 
 /** Where a relative `path` is tried after `cwd`, in order. */
@@ -274,6 +290,7 @@ export function resetPathCache(): void {
   listeners.clear()
   asked.clear()
   anchors.clear()
+  taught.clear()
   if (timer !== undefined) clearTimeout(timer)
   timer = undefined
 }

core/shared/termVersion.ts

@@ -7,5 +7,5 @@
  * so a core release that bumps `core/package.json` (or xterm) without this
  * fails `npm test` (core/README.md, "Releasing the core").
  */
-export const TERM_CORE_VERSION = '0.40.8'
+export const TERM_CORE_VERSION = '0.40.9'
 export const XTERM_VERSION = '6.0.0'

package.json

@@ -1,7 +1,7 @@
 {
   "name": "prism-terminal",
   "productName": "Prism Terminal",
-  "version": "0.53.0",
+  "version": "0.53.1",
   "description": "A tabbed Windows terminal for AI CLIs.",
   "main": "./out/main/index.js",
   "author": "Max",