Ruby » Ruby master

Bug #13928

Updated by nobu (Nobuyoshi Nakada) over 6 years ago

After upgrading a Rails project from 2.3.1 to 2.4.2 I ran into a number of failing tests. Seems like to behaviour of fdiv and conjuction with bigdecimal is wrong. 

 ### Reproduce **Reproduce by running: 
 ```ruby 
 running:** 

 irb(main):001:0> require 'bigdecimal' 
 => true 
 irb(main):002:0> 1.fdiv(1-BigDecimal.new("0")) 
 => 2.1296133346e-314 
 ``` 
 

 Ruby version: ruby 2.4.2p198 (2017-09-14 revision 59899) [x86_64-darwin16] 

 ### I **I would expect the calculation to return 1, which is correctly done if converting the big decimal to a float first: 
 ```ruby 
 first:** 

 irb(main):006:0> 1.fdiv(1-BigDecimal.new("0").to_f) 
 => 1.0 
 ``` 

 ### Using **Using ruby 2.3.1p112, it also looks OK: 
 ```ruby 
 OK:** 

 irb(main):001:0> require 'bigdecimal' 
 => true 
 irb(main):002:0> 1.fdiv(1-BigDecimal.new("0")) 
 => #<BigDecimal:7fb6b8949690,'0.1E1',9(36)> 
 irb(main):003:0> 1.fdiv(1-BigDecimal.new("0")).to_i 
 => 1 

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