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Only generate a mapping at a generated location for the most specific mapping

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#61 9 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
javascript
Domain
devtools

Research direction

Start with the three map.addMapping examples in the issue and determine the expected behavior when generated positions and original locations overlap. Review the source-map mapping-generation entry points and existing tests, if available, then document or test whether the most specific mapping wins or whether multiple mappings are retained.

Written by the indexing model from the issue text.

Description

feat spec

If we have the following mappings, should we generate them all in the source map or only the most specific mapping?

map.addMapping({
  generated: { line: 3, column: 5 }
});
map.addMapping({
  generated: { line: 3, column: 5 },
  original: { line: 6, column: 7 },
  source: 'foo.js'
});
map.addMapping({
  generated: { line: 3, column: 5 },
  original: { line: 6, column: 7 },
  source: 'foo.js',
  name: 'bar'
});

What should be the behavior if there is different original locations for the same generated position? Should we still use the most specific/detailed mapping and ignore the others?

Dominant language
JavaScript
Stars
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Forks
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