util: preserve function names without source map names by privatenumber · Pull Request #65108 · nodejs/node

privatenumber · 2026-08-07T15:37:14Z

Problem

util.getCallSites({ sourceMap: true }) replaced a generated function name with an empty string when a valid source map omitted a name segment. Source-map names are optional, so tooling that consumes mapped call sites loses useful stack context.

For example, a generated foo() call mapped by a source map with an empty names array reported functionName: '' instead of functionName: 'foo'.

Changes

Preserve the V8 function name when the source map does not provide a replacement, matching Node.js's source-mapped stack-trace behavior. A regression fixture covers source maps with no name entries.

Fixes: #65104

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com>

codecov · 2026-08-07T17:11:20Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.31%. Comparing base (e2d7b34) to head (bdae980).
⚠️ Report is 102 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #65108 +/- ##
==========================================
- Coverage 90.31% 90.31% -0.01% 
==========================================
Files 759 759 Lines 248290 248289 -1 Branches 46859 46861 +2 ==========================================
- Hits 224241 224232 -9 + Misses 15472 15468 -4 - Partials 8577 8589 +12

Files with missing lines	Coverage Δ
lib/util.js	`100.00% <100.00%> (ø)`

... and 28 files with indirect coverage changes

🚀 New features to boost your workflow:

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nodejs-github-bot · 2026-08-07T23:17:07Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75631/

nodejs-github-bot · 2026-08-13T16:13:30Z

Landed in c3d68ef

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Signed-off-by: Juan José Arboleda <soyjuanarbol@gmail.com>

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>

privatenumber · 2026-08-07T15:37:14Z

Problem

util.getCallSites({ sourceMap: true }) replaced a generated function name with an empty string when a valid source map omitted a name segment. Source-map names are optional, so tooling that consumes mapped call sites loses useful stack context.

For example, a generated foo() call mapped by a source map with an empty names array reported functionName: '' instead of functionName: 'foo'.

Changes

Preserve the V8 function name when the source map does not provide a replacement, matching Node.js's source-mapped stack-trace behavior. A regression fixture covers source maps with no name entries.

Fixes: #65104

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com>

codecov · 2026-08-07T17:11:20Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.31%. Comparing base (e2d7b34) to head (bdae980).
⚠️ Report is 102 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #65108 +/- ##
==========================================
- Coverage 90.31% 90.31% -0.01% 
==========================================
Files 759 759 Lines 248290 248289 -1 Branches 46859 46861 +2 ==========================================
- Hits 224241 224232 -9 + Misses 15472 15468 -4 - Partials 8577 8589 +12

Files with missing lines	Coverage Δ
lib/util.js	`100.00% <100.00%> (ø)`

... and 28 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

nodejs-github-bot · 2026-08-07T23:17:07Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75631/

nodejs-github-bot · 2026-08-13T16:13:30Z

Landed in c3d68ef

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Signed-off-by: Juan José Arboleda <soyjuanarbol@gmail.com>

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>

privatenumber · 2026-08-07T15:37:14Z

Problem

util.getCallSites({ sourceMap: true }) replaced a generated function name with an empty string when a valid source map omitted a name segment. Source-map names are optional, so tooling that consumes mapped call sites loses useful stack context.

For example, a generated foo() call mapped by a source map with an empty names array reported functionName: '' instead of functionName: 'foo'.

Changes

Preserve the V8 function name when the source map does not provide a replacement, matching Node.js's source-mapped stack-trace behavior. A regression fixture covers source maps with no name entries.

Fixes: #65104

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com>

codecov · 2026-08-07T17:11:20Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.31%. Comparing base (e2d7b34) to head (bdae980).
⚠️ Report is 102 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #65108 +/- ##
==========================================
- Coverage 90.31% 90.31% -0.01% 
==========================================
Files 759 759 Lines 248290 248289 -1 Branches 46859 46861 +2 ==========================================
- Hits 224241 224232 -9 + Misses 15472 15468 -4 - Partials 8577 8589 +12

Files with missing lines	Coverage Δ
lib/util.js	`100.00% <100.00%> (ø)`

... and 28 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

nodejs-github-bot · 2026-08-07T23:17:07Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75631/

nodejs-github-bot · 2026-08-13T16:13:30Z

Landed in c3d68ef

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Signed-off-by: Juan José Arboleda <soyjuanarbol@gmail.com>

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>

privatenumber · 2026-08-07T15:37:14Z

Problem

util.getCallSites({ sourceMap: true }) replaced a generated function name with an empty string when a valid source map omitted a name segment. Source-map names are optional, so tooling that consumes mapped call sites loses useful stack context.

For example, a generated foo() call mapped by a source map with an empty names array reported functionName: '' instead of functionName: 'foo'.

Changes

Preserve the V8 function name when the source map does not provide a replacement, matching Node.js's source-mapped stack-trace behavior. A regression fixture covers source maps with no name entries.

Fixes: #65104

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com>

codecov · 2026-08-07T17:11:20Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.31%. Comparing base (e2d7b34) to head (bdae980).
⚠️ Report is 102 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #65108 +/- ##
==========================================
- Coverage 90.31% 90.31% -0.01% 
==========================================
Files 759 759 Lines 248290 248289 -1 Branches 46859 46861 +2 ==========================================
- Hits 224241 224232 -9 + Misses 15472 15468 -4 - Partials 8577 8589 +12

Files with missing lines	Coverage Δ
lib/util.js	`100.00% <100.00%> (ø)`

... and 28 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

nodejs-github-bot · 2026-08-07T23:17:07Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75631/

nodejs-github-bot · 2026-08-13T16:13:30Z

Landed in c3d68ef

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Signed-off-by: Juan José Arboleda <soyjuanarbol@gmail.com>

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>

privatenumber · 2026-08-07T15:37:14Z

Problem

util.getCallSites({ sourceMap: true }) replaced a generated function name with an empty string when a valid source map omitted a name segment. Source-map names are optional, so tooling that consumes mapped call sites loses useful stack context.

For example, a generated foo() call mapped by a source map with an empty names array reported functionName: '' instead of functionName: 'foo'.

Changes

Preserve the V8 function name when the source map does not provide a replacement, matching Node.js's source-mapped stack-trace behavior. A regression fixture covers source maps with no name entries.

Fixes: #65104

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com>

codecov · 2026-08-07T17:11:20Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.31%. Comparing base (e2d7b34) to head (bdae980).
⚠️ Report is 102 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #65108 +/- ##
==========================================
- Coverage 90.31% 90.31% -0.01% 
==========================================
Files 759 759 Lines 248290 248289 -1 Branches 46859 46861 +2 ==========================================
- Hits 224241 224232 -9 + Misses 15472 15468 -4 - Partials 8577 8589 +12

Files with missing lines	Coverage Δ
lib/util.js	`100.00% <100.00%> (ø)`

... and 28 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

nodejs-github-bot · 2026-08-07T23:17:07Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75631/

nodejs-github-bot · 2026-08-13T16:13:30Z

Landed in c3d68ef

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Signed-off-by: Juan José Arboleda <soyjuanarbol@gmail.com>

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>

privatenumber · 2026-08-07T15:37:14Z

Problem

util.getCallSites({ sourceMap: true }) replaced a generated function name with an empty string when a valid source map omitted a name segment. Source-map names are optional, so tooling that consumes mapped call sites loses useful stack context.

For example, a generated foo() call mapped by a source map with an empty names array reported functionName: '' instead of functionName: 'foo'.

Changes

Preserve the V8 function name when the source map does not provide a replacement, matching Node.js's source-mapped stack-trace behavior. A regression fixture covers source maps with no name entries.

Fixes: #65104

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com>

codecov · 2026-08-07T17:11:20Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.31%. Comparing base (e2d7b34) to head (bdae980).
⚠️ Report is 102 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #65108 +/- ##
==========================================
- Coverage 90.31% 90.31% -0.01% 
==========================================
Files 759 759 Lines 248290 248289 -1 Branches 46859 46861 +2 ==========================================
- Hits 224241 224232 -9 + Misses 15472 15468 -4 - Partials 8577 8589 +12

Files with missing lines	Coverage Δ
lib/util.js	`100.00% <100.00%> (ø)`

... and 28 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

nodejs-github-bot · 2026-08-07T23:17:07Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75631/

nodejs-github-bot · 2026-08-13T16:13:30Z

Landed in c3d68ef

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Signed-off-by: Juan José Arboleda <soyjuanarbol@gmail.com>

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>

privatenumber · 2026-08-07T15:37:14Z

Problem

util.getCallSites({ sourceMap: true }) replaced a generated function name with an empty string when a valid source map omitted a name segment. Source-map names are optional, so tooling that consumes mapped call sites loses useful stack context.

For example, a generated foo() call mapped by a source map with an empty names array reported functionName: '' instead of functionName: 'foo'.

Changes

Preserve the V8 function name when the source map does not provide a replacement, matching Node.js's source-mapped stack-trace behavior. A regression fixture covers source maps with no name entries.

Fixes: #65104

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com>

codecov · 2026-08-07T17:11:20Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.31%. Comparing base (e2d7b34) to head (bdae980).
⚠️ Report is 102 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #65108 +/- ##
==========================================
- Coverage 90.31% 90.31% -0.01% 
==========================================
Files 759 759 Lines 248290 248289 -1 Branches 46859 46861 +2 ==========================================
- Hits 224241 224232 -9 + Misses 15472 15468 -4 - Partials 8577 8589 +12

Files with missing lines	Coverage Δ
lib/util.js	`100.00% <100.00%> (ø)`

... and 28 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

nodejs-github-bot · 2026-08-07T23:17:07Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75631/

nodejs-github-bot · 2026-08-13T16:13:30Z

Landed in c3d68ef

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Signed-off-by: Juan José Arboleda <soyjuanarbol@gmail.com>

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>

privatenumber · 2026-08-07T15:37:14Z

Problem

util.getCallSites({ sourceMap: true }) replaced a generated function name with an empty string when a valid source map omitted a name segment. Source-map names are optional, so tooling that consumes mapped call sites loses useful stack context.

For example, a generated foo() call mapped by a source map with an empty names array reported functionName: '' instead of functionName: 'foo'.

Changes

Preserve the V8 function name when the source map does not provide a replacement, matching Node.js's source-mapped stack-trace behavior. A regression fixture covers source maps with no name entries.

Fixes: #65104

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com>

codecov · 2026-08-07T17:11:20Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.31%. Comparing base (e2d7b34) to head (bdae980).
⚠️ Report is 102 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #65108 +/- ##
==========================================
- Coverage 90.31% 90.31% -0.01% 
==========================================
Files 759 759 Lines 248290 248289 -1 Branches 46859 46861 +2 ==========================================
- Hits 224241 224232 -9 + Misses 15472 15468 -4 - Partials 8577 8589 +12

Files with missing lines	Coverage Δ
lib/util.js	`100.00% <100.00%> (ø)`

... and 28 files with indirect coverage changes

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

nodejs-github-bot · 2026-08-07T23:17:07Z

CI: https://ci.nodejs.org/job/node-test-pull-request/75631/

nodejs-github-bot · 2026-08-13T16:13:30Z

Landed in c3d68ef

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Signed-off-by: Juan José Arboleda <soyjuanarbol@gmail.com>

Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com> PR-URL: #65108Fixes: #65104 Reviewed-By: Chengzhong Wu <legendecas@gmail.com> Reviewed-By: Aviv Keller <me@aviv.sh> Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>

util: preserve function names without source map names
bdae980
Signed-off-by: Hiroki Osame <hiroki.osame@gmail.com>

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privatenumber mentioned this pull request Aug 8, 2026
Missing function names in getCallSites() with sourcemaps enabled privatenumber/tsx#692
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nodejs-github-bot merged commit c3d68ef into nodejs:mainAug 13, 2026
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This was referenced Aug 20, 2026
2026-09-01, Version 22.23.3 'Jod' (LTS) #65443
Closed
2026-09-01, Version 22.23.3 'Jod' (LTS) #65448
Open

lazerg mentioned this pull request Aug 22, 2026
util: keep function name for mapped call sites #65107
Closed

aduh95 mentioned this pull request Aug 25, 2026
2026-08-26, Version 26.8.0 (Current) #65551
Merged