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Failing to load coverage

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Assessment

Difficulty
4/5
Estimated time
1-2 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
ios, ruby
Domain
testing, tooling

Research direction

Start at lib/slather/project.rb, especially pathnames_per_binary and profdata_coverage_files, which the reported stack trace identifies. Check how coverage data is located for the described workspace and test harness, then compare the behavior with the Xcode 14 and 15 reports. Done means Slather handles this setup without the coverage-loading and JSON parsing errors, with a regression test for the reported case.

Written by the indexing model from the issue text.

Description

This might be because of how my workspace is setup, but whenever I run slather I get error: Failed to load coverage .... no coverage data found. I know there is coverage, because if I open the xcresults, I see all the coverage data.

My project has a testing harness workspace that contains all the frameworks to be tested which are pulled in a submodules. The framework projects themselves have the tests in them, but the testing harness contains a project that has all the test plans.

Here is the full error message, any thoughts?

<user>@<machine> Debug % slather coverage -s --scheme <project name>NoHardwareTests --workspace /Users/<user>/Projects/<project name>-Harness/<project name>Harness.xcworkspace /Users/<user>/Projects/<project name>-Harness/<project name>TestHarness/<project name>TestHarness.xcodeproj
Slathering...
error: Failed to load coverage: '/Users/<user>/Library/Developer/Xcode/DerivedData/<project name>Harness-czjbpsoximqkdwftaumjsowuxllm/Build/Products/Debug/<project name>TestHarnessUnitTests.xctest/Contents/MacOS/<project name>TestHarnessUnitTests': No coverage data found
error: Could not load coverage information
/Users/<user>/.rubies/ruby-3.1.4/lib/ruby/3.1.0/json/common.rb:216:in `parse': 859: unexpected token at '' (JSON::ParserError)
	from /Users/<user>/.rubies/ruby-3.1.4/lib/ruby/3.1.0/json/common.rb:216:in `parse'
	from /Users/<user>/.gem/ruby/3.1.4/gems/slather-2.7.4/lib/slather/project.rb:135:in `pathnames_per_binary'
	from /Users/<user>/.gem/ruby/3.1.4/gems/slather-2.7.4/lib/slather/project.rb:124:in `block in profdata_coverage_files'
	from /Users/<user>/.gem/ruby/3.1.4/gems/slather-2.7.4/lib/slather/project.rb:123:in `each'
	from /Users/<user>/.gem/ruby/3.1.4/gems/slather-2.7.4/lib/slather/project.rb:123:in `profdata_coverage_files'
	from /Users/<user>/.gem/ruby/3.1.4/gems/slather-2.7.4/lib/slather/project.rb:98:in `coverage_files'
	from /Users/<user>/.gem/ruby/3.1.4/gems/slather-2.7.4/lib/slather/coverage_service/simple_output.rb:17:in `post'
	from /Users/<user>/.gem/ruby/3.1.4/gems/slather-2.7.4/lib/slather/command/coverage_command.rb:101:in `post'
	from /Users/<user>/.gem/ruby/3.1.4/gems/slather-2.7.4/lib/slather/command/coverage_command.rb:61:in `execute'
	from /Users/<user>/.gem/ruby/3.1.4/gems/clamp-1.3.2/lib/clamp/command.rb:66:in `run'
	from /Users/<user>/.gem/ruby/3.1.4/gems/clamp-1.3.2/lib/clamp/subcommand/execution.rb:18:in `execute'
	from /Users/<user>/.gem/ruby/3.1.4/gems/clamp-1.3.2/lib/clamp/command.rb:66:in `run'
	from /Users/<user>/.gem/ruby/3.1.4/gems/clamp-1.3.2/lib/clamp/command.rb:140:in `run'
	from /Users/<user>/.gem/ruby/3.1.4/gems/slather-2.7.4/bin/slather:17:in `<top (required)>'
	from /Users/<user>/.gem/ruby/3.1.4/bin/slather:25:in `load'
	from /Users/<user>/.gem/ruby/3.1.4/bin/slather:25:in `<main>'

edit: this is on Xcode 15 if it matters. It also doesn't seem to work on Xcode 14.

Dominant language
Ruby
Stars
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Forks
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Avg merge
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Merged PRs (30d)
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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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