How Go cache tests

A presentation at Go 1.10 Release Party.

Transcript

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2. Seiji Takahashi
   @__timakin__
   • Career
   • DeNA
   • Platform Development
   • Serverside Engineering (Perl)

   • Translimit
   • Game Development: Craft Warrirors
   • Game Client Side (Cocos-2dx, C++)

   • Gunosy
   • Application Dev: LUCRA
   • Serverside Engineering (Go)
   • iOS Client Side (Swift)
   • Engieering
   • Language: Go (Contributed), Swift
   • Platform: GAE, AWS
   

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   if the test executable and 

   command line match a previous run and 

   the files and environment variables consulted by that run
   have not changed either, go test will print the previous test
   output, replacing the elapsed time with the string “(cached).”
   

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7. 8IBUJTUFTUDBDIJOH
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   • -cpu
   • -list
   • -parallel
   • -run
   • -short
   • -v
   

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   • -count=1
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   • go clean -testcache
   

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9. 8IBUJTUFTUDBDIJOH
   Benchmarking, and cpu/mem profiling might slightly
   change from run to run.
   So they aren’t cached.
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20. In the process of code-reading and implementing,
    
    code is often written near an original caching execution.
    
    By chance I’ve read that code before I actually use the
    
    caching strategy.
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