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Unexpected token at ''

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
36/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
objective-c, ruby, swift
Domain
testing-qa

Research direction

Start with Slather::Project#pathnames_per_binary in lib/slather/project.rb:135, where the stack trace shows JSON parsing fails after coverage loading reports no data for the binary. Check how the coverage command handles that failed load and identify why the JSON input is empty. Done means the failure is reported or handled clearly for this Xcode coverage case; the issue gives no reproduction project or test to run.

Written by the indexing model from the issue text.

Description

Hi,
I'm trying to use slather to convert Xcode coverage output to Cobertura XML format.
The project contains both objective-c and swift files.

The output from Xcode seems OK, there is the profdata file which is not empty, also the .gcdo, .dia etc files...

But slather ends up with the below error:

Slathering...

Processing coverage file: /Users/marcbiosca/Library/Developer/Xcode/DerivedData/MobileSDK-cdwqzqnpwqkarzdkewkdznfastpf/Build/ProfileData/21968B43-AFA4-4330-B505-45D1D0DB1F57/Coverage.profdata
Against binary files:
	/Users/marcbiosca/Library/Developer/Xcode/DerivedData/MobileSDK-cdwqzqnpwqkarzdkewkdznfastpf/Build/Products/PlotDebug-iphonesimulator/libSelligentMobile.a

error: /Users/marcbiosca/Library/Developer/Xcode/DerivedData/MobileSDK-cdwqzqnpwqkarzdkewkdznfastpf/Build/Products/PlotDebug-iphonesimulator/libSelligentMobile.a: Failed to load coverage: No coverage data found
error: Could not load coverage information

/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/json/common.rb:156:in 'parse': 767: unexpected token at '' (JSON::ParserError)
	from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/json/common.rb:156:in 'parse'
	from /Library/Ruby/Gems/2.6.0/gems/slather-2.7.2/lib/slather/project.rb:135:in 'pathnames_per_binary'
	from /Library/Ruby/Gems/2.6.0/gems/slather-2.7.2/lib/slather/project.rb:124:in 'block in profdata_coverage_files'
	from /Library/Ruby/Gems/2.6.0/gems/slather-2.7.2/lib/slather/project.rb:123:in 'each'
	from /Library/Ruby/Gems/2.6.0/gems/slather-2.7.2/lib/slather/project.rb:123:in 'profdata_coverage_files'
	from /Library/Ruby/Gems/2.6.0/gems/slather-2.7.2/lib/slather/project.rb:98:in 'coverage_files'
	from /Library/Ruby/Gems/2.6.0/gems/slather-2.7.2/lib/slather/coverage_service/simple_output.rb:17:in 'post'
	from /Library/Ruby/Gems/2.6.0/gems/slather-2.7.2/lib/slather/command/coverage_command.rb:101:in 'post'
	from /Library/Ruby/Gems/2.6.0/gems/slather-2.7.2/lib/slather/command/coverage_command.rb:61:in 'execute'
	from /Library/Ruby/Gems/2.6.0/gems/clamp-1.3.2/lib/clamp/command.rb:66:in 'run'
	from /Library/Ruby/Gems/2.6.0/gems/clamp-1.3.2/lib/clamp/subcommand/execution.rb:18:in 'execute'
	from /Library/Ruby/Gems/2.6.0/gems/clamp-1.3.2/lib/clamp/command.rb:66:in 'run'
	from /Library/Ruby/Gems/2.6.0/gems/clamp-1.3.2/lib/clamp/command.rb:140:in 'run'
	from /Library/Ruby/Gems/2.6.0/gems/slather-2.7.2/bin/slather:17:in '<top (required)>'
	from /usr/local/bin/slather:23:in 'load'
	from /usr/local/bin/slather:23:in '<main>'

Any idea what could go wrong here?

Dominant language
Ruby
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Merged PRs (30d)
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