Fix empty case statement normalizes to condition expression #6915
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asterite
reviewed
Oct 7, 2018
| @@ -13,6 +13,14 @@ describe "Code gen: case" do | |||
| run("require \"prelude\"; case 1; when 0; 2; else; 3; end").to_i.should eq(3) | |||
| end | |||
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| it "codegens case without whens" do | |||
| run("require \"prelude\"; case 1; end").to_string.should eq "" | |||
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I'm not sure it's a good idea to turn a nil into a string like this... it probably works, but it's not clear why (I wouldn't add a test for this if the normalizer is already tested, and same for the test below).
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to_string actually just returns @output of Crystal::SpecRunOutput which is already a string.
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But I can remove these specs, if their not considered particularly useful.
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Ah, you are right. You can leave them if you want.
asterite
approved these changes
Oct 7, 2018
bcardiff
approved these changes
Oct 7, 2018
sdogruyol
approved these changes
Oct 8, 2018
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After #6367, an empty case statement (without
whenorelse) would be normalized to just the condition. This means thatcase "foo"; elseis normalized to"foo". But that's semantically incorrect. The return type of an emptycaseshould just benilbecause there is no branch that could return anything else.This fix adds a
nilafter the condition when there are nowhenorelsebranches, so the example normalizes to"foo"; nil.This PR also adds two codegen specs which are not necessary to document this fix, but they should have been added in #6367.