CSV coming out as pipe-delimited
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I created a Rails file outputting values separated by commas, called posts.csv.erb.

When I click on the link, it downloads as a CSV file, but the commas are now pipes. Also, Vim tries to auto-correct the commas into pipes for some reason (but I got around that, so they are actually commas). It works fine if I call the file posts.txt.erb - I see actual commas. But somehow it seems Rails or ERB wants to output pipes for a CSV file?