[Unhandled Error] Soft Assertion Failed

[vs-code-engineering]

Error Message

Soft Assertion Failed

Stack Trace

    at FYt (./src/vs/base/common/assert.ts:63:20)
    at softAssert (./src/vs/editor/browser/widget/diffEditor/diffEditorViewModel.ts:527:2)
    at (anonymous) (./src/vs/editor/browser/widget/diffEditor/diffEditorViewModel.ts:178:14)
    at s (./src/vs/editor/browser/widget/diffEditor/diffEditorViewModel.ts:175:7)
    at updateUnchangedRegions (./src/vs/editor/browser/widget/diffEditor/diffEditorViewModel.ts:312:4)
    at fn (./src/vs/base/common/observableInternal/transaction.ts:19:2)
    at transaction (./src/vs/editor/browser/widget/diffEditor/diffEditorViewModel.ts:310:3)

Raw Stack Trace (minified)

Error: Soft Assertion Failed     at FYt (out/vs/workbench/workbench.desktop.main.js:386:325)     at new a (out/vs/workbench/workbench.desktop.main.js:850:24683)     at out/vs/workbench/workbench.desktop.main.js:850:18815     at Array.map (<anonymous>)     at s (out/vs/workbench/workbench.desktop.main.js:850:18755)     at out/vs/workbench/workbench.desktop.main.js:850:21920     at Ji (out/vs/workbench/workbench.desktop.main.js:406:109163)     at out/vs/workbench/workbench.desktop.main.js:850:21913

Details

Property	Value
Bucket ID	e734f19e-0300-0a78-ae46-d326665ac84b
Version	1.113.0
Commit	cfbea10c
Last Seen	Thu Mar 26 2026 23:59:02 GMT+0000 (Coordinated Universal Time)
Platforms	Mac, Windows, Linux
Product	VSCode

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This issue was automatically created from the VS Code Errors Dashboard

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Trend

This error is increasing across recent stable releases:

Version	Users	Hits
1.107.0	4.1K	10.4K
1.107.1	11K	28K
1.108.0	6.9K	17K
1.108.1	9.4K	23.2K
1.108.2	19.1K	47.1K
1.110.0	29.1K	64.1K
1.110.1	38.4K	88K
1.113.0	25.4K	34.4K

1.113.0 was released 3 days ago and already has 25.4K users affected. All platforms (Mac, Windows, Linux).

Related Issues

This is a new-format replacement for the existing open old-format issue #211616 which tracks the same Soft Assertion Failed in diffEditorViewModel.ts (updateUnchangedRegions → softAssert). Other related closed issues: #267092, #260072, #248828, #232394, #229302.

The root cause is in src/vs/editor/browser/widget/diffEditor/diffEditorViewModel.ts — a soft assertion failure triggered during updateUnchangedRegions via softAssert at line 527.

Generated by errors-triage · ◷

[vs-code-engineering]

Related Error Buckets

These additional error buckets are tracked by this issue (v1.123.0):

Bucket ID	Error Message	Version
875fae1f	Soft Assertion Failed	1.123.0

Same Soft Assertion Failed error in diffEditorViewModel.ts with a different stack signature (30.3K users, 40.9K hits).

Generated by errors-triage · ● 25.8M · ◷

[vs-code-engineering]

Related Error Buckets

These additional error buckets are tracked by this issue (v1.128.0-insider):

Bucket ID	Error Message	Users	Hits	Version
f3d4f377	Soft Assertion Failed	36	43	1.128.0-insider

Same Soft Assertion Failed in diffEditorViewModel.ts (softAssert ~L527), reached via the unchanged-regions autorun (hideUnchangedRegionsFeature.ts → diff editor view model) during a text-model edit. Different stack signature, same assertion. Surfaced as a new bucket ID on the 1.128.0-insider regression scan; linked here rather than filed separately.

Generated by errors-regression-scan · 1.7K AIC · ⌖ 69.9 AIC · ⊞ 45.6K · ◷

[vs-code-engineering]

Related Error Buckets

This error bucket continues to appear in v1.129.0-insider (previously tracked since v1.113.0 — surfaced as a new bucket ID due to minification drift):

Bucket ID	Error Message	Users	Hits	Version
62128b74	Soft Assertion Failed	31	47	1.129.0-insider

Product: VSCode
Regression type: new bucket variant (continuing error)

Surfaced as a "new" bucket in the 1.129.0-insider regression scan (baseline 1.128.0 stable). The deminified stack matches this issue: assert.ts:63 → softAssert at diffEditorViewModel.ts:527, reached via the unchanged-regions autorun (autorunImpl.ts → transaction.ts) during a text-model resolve/reload edit. Same assertion, different stack signature. Linked here rather than filed separately.

Generated by errors-regression-scan · 576.7 AIC · ⌖ 27.4 AIC · ⊞ 45.6K · ◷

[vs-code-engineering]

Related Error Buckets

This error continues to appear in v1.129.0-insider (previously tracked since v1.113.0 — surfacing as new bucket IDs due to minification drift). Two bucket-ID variants of the same Soft Assertion Failed were seen in the 1.129.0-insider regression scan:

Bucket ID	Error Message	Users	Hits	Version	Commit
62128b74	Soft Assertion Failed	31	47	1.129.0-insider	e8a3eada
1ed37066	Soft Assertion Failed	41	55	1.129.0-insider	323fd70

Product: VSCode
Regression type: continuing error (new bucket-ID variants)

Both deminify to the same signature as this issue: assert.ts:63 → softAssert at diffEditorViewModel.ts (~L527/528), reached via the unchanged-regions autorun (autorunImpl.ts → transaction.ts) during a text-model resolve/reload edit. Same assertion, different stack signatures. Linked here rather than filed separately. This consolidates the earlier single-bucket comment for v1.129.0-insider.

Generated by errors-regression-scan · 636.6 AIC · ⌖ 27.6 AIC · ⊞ 45.6K · ◷

[vs-code-engineering]

Related Error Buckets

This error continues to appear in v1.130.0-insider (previously tracked since v1.113.0 — surfacing as new bucket IDs due to minification drift):

Bucket ID	Error Message	Users	Hits	Version	Commit
7efcaaed	Soft Assertion Failed	22	28	1.130.0-insider	bc2ac764

Product: VSCode
Regression type: continuing error (new bucket-ID variant)

Surfaced as a "new" bucket in the 1.130.0-insider regression scan (baseline 1.129.0 stable). The deminified stack matches this issue: assert.ts:63 → softAssert at diffEditorViewModel.ts:527, reached via the unchanged-regions autorun (autorunImpl.ts → transaction.ts) during a text-model resolve/reload edit. Same assertion, different stack signature. Linked here rather than filed separately.

Generated by errors-regression-scan · 640.5 AIC · ⌖ 27.4 AIC · ⊞ 45.6K · ◷

[vs-code-engineering]

Related Error Buckets

This error continues to appear in v1.131.0-insider (previously tracked since v1.113.0 — surfacing as new bucket IDs due to minification drift):

Bucket ID	Error Message	Users	Hits	Version	Commit
16adec57	Soft Assertion Failed	29	38	1.131.0-insider	9aab2f5

Product: VSCode
Regression type: continuing error (new bucket-ID variant)

Surfaced as a "new" bucket in the 1.131.0-insider regression scan (baseline 1.130.0 stable). The deminified stack matches this issue: assert.ts:63 → softAssert at diffEditorViewModel.ts:528, reached via the unchanged-regions autorun (hideUnchangedRegionsFeature.ts:83 → autorunImpl.ts → transaction.ts) during a diff-editor view-model update. Same assertion, different stack signature. Linked here rather than filed separately.

Generated by errors-regression-scan · 561.1 AIC · ⌖ 24.5 AIC · ⊞ 46.2K · ◷