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Type:
Spec Change
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Resolution: Unresolved
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Priority:
Minor - P4
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None
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Component/s: Extended JSON
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None
MRI Ruby and JRuby differ in how they stringify large floats.
MRI:
irb(main):014:0> 1e15.to_s
=> "1.0e+15"
JRuby:
irb(main):001:0> 1e15.to_s
=> "1000000000000000.0"
1e14 in both interpreters stringifies the same:
irb(main):003:0> 1e14.to_s
=> "100000000000000.0"
The spec tests implicitly require that there is a single stringification of floats done by all implementations, as the following test fails on JRuby:
2) BSON Corpus spec tests (double.json): Double type valid: -1.2345678901234568e+18 - precision adjusted for Ruby converts bson to canonical extended json Failure/Error: decoded_canonical_bson.as_extended_json.should == test.canonical_extjson_doc expected: {"d"=>{"$numberDouble"=>"-1.2345678901234568e+18"}} got: {"d"=>{"$numberDouble"=>"-1234567890123456770.0"}} (using ==) Diff: @@ -1,2 +1,2 @@ -"d" => {"$numberDouble"=>"-1.2345678901234568e+18"}, +"d" => {"$numberDouble"=>"-1234567890123456770.0"}, # ./spec/spec_tests/corpus_spec.rb:35:in `block in <main>'
The extended json spec has the following language regarding float stringification:
>
{"$numberDouble": <64-bit signed floating point as a decimal string>}This language does not mandate a particular representation.
When I changed Ruby extended json serializer to use %g format, a number of other tests failed that expect zero floats to be serialized to "0.0" rather than "0". Example:
7) BSON Corpus spec tests (double.json): Double type valid: 0.0 converts bson to canonical extended json Failure/Error: decoded_canonical_bson.as_extended_json.should == test.canonical_extjson_doc expected: {"d"=>{"$numberDouble"=>"0.0"}} got: {"d"=>{"$numberDouble"=>"0"}} (using ==) Diff: @@ -1,2 +1,2 @@ -"d" => {"$numberDouble"=>"0.0"}, +"d" => {"$numberDouble"=>"0"}, # ./spec/spec_tests/corpus_spec.rb:35:in `block in <main>' 8) BSON Corpus spec tests (double.json): Double type valid: -0.0 converts bson to canonical extended json Failure/Error: decoded_canonical_bson.as_extended_json.should == test.canonical_extjson_doc expected: {"d"=>{"$numberDouble"=>"-0.0"}} got: {"d"=>{"$numberDouble"=>"-0"}} (using ==) Diff: @@ -1,2 +1,2 @@ -"d" => {"$numberDouble"=>"-0.0"}, +"d" => {"$numberDouble"=>"-0"}, # ./spec/spec_tests/corpus_spec.rb:35:in `block in <main>'
- related to
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RUBY-2066 Extended json serialization
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- Closed
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