Microsoft/vscode

[engineering] sourcemap issues

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#251,233 opened on Jun 11, 2025

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 (4 comments) (0 reactions) (1 assignee)TypeScript (39,847 forks)batch import
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Description

  1. source files are duplicated inside sourcemap
❯ npm run gulp compile-build-without-mangling

❯ cat out-build/main.js.map | jq .sourceRoot
"file:///Users/tmm1/code/vscode/src"

❯ cat out-build/main.js.map | jq .sources
[
  "file:///Users/tmm1/code/vscode/src/main.ts",
  "main.ts"
]
  1. duplicated paths are further corrupted during minification
❯ npm run gulp minify-vscode

❯ cat out-vscode/main.js.map | jq '.sources[0,1]'
"../file:/Users/tmm1/code/vscode/src/vs/base/common/performance.ts"
"../vs/base/common/performance.ts"

❯ cat out-vscode-min/main.js.map | jq '.sources[0,1]'
"./file:/Users/tmm1/code/vscode/src/vs/base/common/performance.ts"
"vs/base/common/performance.ts"

Contributor guide

Research direction
Examine the Gulp build scripts for sourcemap generation, specifically the compile build without mangling task, and identify where duplicate source paths are introduced.
Tech stack
typescriptnodejs
Domain
build system
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Mostly clear
Prerequisites
GitnpmNode.js
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
40