Reapply "fix: restore terminal redraw after tab reactivation (#11275)"

This reverts commit b5fa811137.

tabby-terminal/src/api/baseTerminalTab.component.ts

@@ -9,6 +9,7 @@ import { BaseSession } from '../session'
 
 import { Frontend } from '../frontends/frontend'
 import { XTermFrontend, XTermWebGLFrontend } from '../frontends/xtermFrontend'
+import { syncTerminalVisibility } from '../frontends/visibility'
 import { ResizeEvent, BaseTerminalProfile } from './interfaces'
 import { TerminalDecorator } from './decorator'
 import { SearchPanelComponent } from '../components/searchPanel.component'
@@ -446,17 +447,7 @@ export class BaseTerminalTabComponent<P extends BaseTerminalProfile> extends Bas
             .pipe(debounce(visibility => interval(visibility ? 0 : INACTIVE_TAB_UNLOAD_DELAY)))
             .subscribe(visibility => {
                 if (this.frontend instanceof XTermFrontend) {
-                    if (visibility) {
-                        // this.frontend.resizeHandler()
-                        const term = this.frontend.xterm as any
-                        term._core._renderService?.clear()
-                        term._core._renderService?.handleResize(term.cols, term.rows)
-                    } else {
-                        this.frontend.xterm.element?.querySelectorAll('canvas').forEach(c => {
-                            c.height = c.width = 0
-                            c.style.height = c.style.width = '0px'
-                        })
-                    }
+                    syncTerminalVisibility(this.frontend, visibility)
                 }
             })
     }

tabby-terminal/src/frontends/visibility.test.js

@@ -0,0 +1,38 @@
+import assert from 'node:assert/strict'
+import test from 'node:test'
+
+import { syncTerminalVisibility } from './visibility.ts'
+
+test('syncTerminalVisibility reactivates the frontend when the tab becomes visible', () => {
+    let reactivated = 0
+    let deactivated = 0
+
+    syncTerminalVisibility({
+        reactivateAfterVisibilityChange: () => {
+            reactivated++
+        },
+        deactivateAfterVisibilityChange: () => {
+            deactivated++
+        },
+    }, true)
+
+    assert.equal(reactivated, 1)
+    assert.equal(deactivated, 0)
+})
+
+test('syncTerminalVisibility releases hidden-tab resources when the tab becomes invisible', () => {
+    let reactivated = 0
+    let deactivated = 0
+
+    syncTerminalVisibility({
+        reactivateAfterVisibilityChange: () => {
+            reactivated++
+        },
+        deactivateAfterVisibilityChange: () => {
+            deactivated++
+        },
+    }, false)
+
+    assert.equal(reactivated, 0)
+    assert.equal(deactivated, 1)
+})

tabby-terminal/src/frontends/visibility.ts

@@ -0,0 +1,12 @@
+export interface VisibilityManagedTerminalFrontend {
+    reactivateAfterVisibilityChange: () => void
+    deactivateAfterVisibilityChange: () => void
+}
+
+export function syncTerminalVisibility (frontend: VisibilityManagedTerminalFrontend, visible: boolean): void {
+    if (visible) {
+        frontend.reactivateAfterVisibilityChange()
+    } else {
+        frontend.deactivateAfterVisibilityChange()
+    }
+}

tabby-terminal/src/frontends/xtermFrontend.ts

@@ -98,15 +98,20 @@ export class XTermFrontend extends Frontend {
         this.hostApp = injector.get(HostAppService)
         this.themes = injector.get(ThemesService)
 
-        this.xterm = new Terminal({
+        const terminalOptions = {
             allowTransparency: true,
             allowProposedApi: true,
-            overviewRulerWidth: 8,
             windowsPty: process.platform === 'win32' ? {
-                backend: this.configService.store.terminal.useConPTY ? 'conpty' : 'winpty',
+                backend: this.configService.store.terminal.useConPTY ? 'conpty' as const : 'winpty' as const,
                 buildNumber: getWindows10Build(),
             } : undefined,
-        })
+        }
+        ;(terminalOptions as Record<string, unknown>).overviewRuler = {
+            width: 8,
+            showBottomBorder: false,
+            showTopBorder: false,
+        }
+        this.xterm = new Terminal(terminalOptions)
         this.flowControl = new FlowControl(this.xterm)
         this.xtermCore = this.xterm['_core']
 
@@ -360,6 +365,17 @@ export class XTermFrontend extends Frontend {
         delete this.resizeObserver
     }
 
+    reactivateAfterVisibilityChange (): void {
+        this.resizeHandler()
+    }
+
+    deactivateAfterVisibilityChange (): void {
+        this.xterm.element?.querySelectorAll('canvas').forEach(c => {
+            c.height = c.width = 0
+            c.style.height = c.style.width = '0px'
+        })
+    }
+
     destroy (): void {
         super.destroy()
         this.webGLAddon?.dispose()