Clamp viewport line numbers in getCompletelyVisibleViewRange

[Copilot]

getCompletelyVisibleViewRange() and getCompletelyVisibleViewRangeAtScrollTop() use line numbers from viewLayout.getLinesViewportData() without clamping, causing Cannot read properties of undefined (reading 'getViewLineMinColumn') when viewport data is stale after a model change (e.g., during editor input transitions triggering updateOptions → config change → mainThreadEditor reading visible ranges).

The sibling method getVisibleRangesPlusViewportAboveBelow() already clamps correctly. Applied the same Math.max(1, ...) / Math.min(this.getLineCount(), ...) pattern to both methods.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• redirector.gvt1.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --no-sandbox --crashpad-handler-pid=6743 --enable-crash-reporter=20c4b431-3a5f-48a4-8742-e59c04dc8e8b,no_channel --user-data-dir=/tmp/vscode-tests-1771360825840 --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,8433739414279652828,12731713229849147524,262144 --enable-features=PdfUseShowSaveFilePicker --disable-features=LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TraceSiteInstanceGetProcessCreation --variations-seed-version --trace-process-track-uuid=3190708989122997041 (dns block)
  • Triggering command: .build/electron/code-oss .build/electron/code-oss test/unit/electron/index.js --crash-reporter-directory=/home/REDACTED/work/vscode/vscode/.build/crashes --run src/vs/editor/test/browser/viewModel/viewModelImpl.test.ts (dns block)
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --no-sandbox --crashpad-handler-pid=8509 --enable-crash-reporter=20c4b431-3a5f-48a4-8742-e59c04dc8e8b,no_channel --user-data-dir=/tmp/vscode-tests-1771361181084 --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,10414167561713765848,5024585337175371328,262144 --enable-features=PdfUseShowSaveFilePicker --disable-features=LocalNetworkAccessChecks,ScreenAIOCREnabled,SpareRendererForSitePerProcess,TraceSiteInstanceGetProcessCreation --variations-seed-version --trace-process-track-uuid=3190708989122997041 e_modules/.bin/sh Map --inlineSourbash --sourceMap --inlineSources sh (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

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This section details on the original issue you should resolve

<issue_title>[Unhandled Error] Cannot read properties of undefined (reading 'getViewLineMinColumn')</issue_title>
<issue_description>Issue created from VS Code Errors Analysis Dashboard

Error Bucket

278407ff-ebf2-a32b-7ba2-246abc37bf68

Error Message

Cannot read properties of undefined (reading 'getViewLineMinColumn')

Stack Trace

    at Phs.getViewLineMinColumn (./src/vs/editor/common/viewModel/viewModelLines.ts:739:61)
    at Vhs.getLineMinColumn (./src/vs/editor/common/viewModel/viewModelImpl.ts:804:21)
    at Vhs.getCompletelyVisibleViewRange (./src/vs/editor/common/viewModel/viewModelImpl.ts:685:29)
    at Vhs.getVisibleRanges (./src/vs/editor/common/viewModel/viewModelImpl.ts:626:32)
    at _u.getVisibleRanges (./src/vs/editor/browser/widget/codeEditor/codeEditorWidget.ts:563:35)
    at I4.f (./src/vs/workbench/api/browser/mainThreadEditor.ts:92:21)
    at I4.readFromEditor (./src/vs/workbench/api/browser/mainThreadEditor.ts:36:55)
    at GMs.p (./src/vs/workbench/api/browser/mainThreadEditor.ts:214:34)
    at i (./src/vs/workbench/api/browser/mainThreadEditor.ts:291:10)
    at updateProperties (./src/vs/workbench/api/browser/mainThreadEditor.ts:317:4)
    at L.C (./src/vs/base/common/event.ts:1295:12)
    at L.D (./src/vs/base/common/event.ts:1306:8)
    at L.fire (./src/vs/base/common/event.ts:1330:8)
    at cde.value (./src/vs/editor/browser/widget/codeEditor/codeEditorWidget.ts:306:28)
    at L.C (./src/vs/base/common/event.ts:1295:12)
    at L.fire (./src/vs/base/common/event.ts:1326:8)
    at Gue.C (./src/vs/editor/browser/config/editorConfiguration.ts:113:20)
    at Gue.updateOptions (./src/vs/editor/browser/config/editorConfiguration.ts:174:7)
    at _u.updateOptions (./src/vs/editor/browser/widget/codeEditor/codeEditorWidget.ts:442:22)
    at _u.rc (./src/vs/editor/browser/widget/codeEditor/embeddedCodeEditorWidget.ts:55:8)
    at cde.value (./src/vs/editor/browser/widget/codeEditor/embeddedCodeEditorWidget.ts:47:94)
    at L.C (./src/vs/base/common/event.ts:1295:12)
    at L.D (./src/vs/base/common/event.ts:1306:8)
    at L.fire (./src/vs/base/common/event.ts:1330:8)
    at cde.value (./src/vs/editor/browser/widget/codeEditor/codeEditorWidget.ts:301:34)
    at L.C (./src/vs/base/common/event.ts:1295:12)
    at L.fire (./src/vs/base/common/event.ts:1326:8)
    at Gue.C (./src/vs/editor/browser/config/editorConfiguration.ts:113:20)
    at Gue.updateOptions (./src/vs/editor/browser/config/editorConfiguration.ts:174:7)
    at fl.updateOptions (./src/vs/editor/browser/widget/codeEditor/codeEditorWidget.ts:442:22)
    at HRe.Mb (./src/vs/workbench/browser/parts/editor/textCodeEditor.ts:49:22)
    at HRe.Qb (./src/vs/workbench/browser/parts/editor/textEditor.ts:323:8)
    at HRe.setInput (./src/vs/workbench/browser/parts/editor/textEditor.ts:248:7)
    at async HRe.setInput (./src/vs/workbench/contrib/files/browser/editors/textFileEditor.ts:106:2)
    at async Pet.S (./src/vs/workbench/browser/parts/editor/editorPanes.ts:466:3)
    at async Pet.L (./src/vs/workbench/browser/parts/editor/editorPanes.ts:259:33)
    at async Pet.openEditor (./src/vs/workbench/browser/parts/editor/editorPanes.ts:136:10)
    at async (./src/vs/workbench/browser/parts/editor/editorGroupView.ts:1260:48)

Related Information

• Version: 1.109.4
• Commit: c3a26841
• Platforms: Mac, Windows, Linux
• Dashboard: View in Errors Dashboard

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This issue was created from the VS Code Errors Dashboard</issue_description>

<agent_instructions>follow instructions from ./.github/prompts/fix-error.prompt.md to investigate this unhandled error.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes [Unhandled Error] Cannot read properties of undefined (reading 'getViewLineMinColumn') #295854

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[alexdima]

Let's close in favor of #296709