Testing Guidelines

Frost uses Hspec with Hspec Discover for its testing framework. This approach provides a structured and expressive way to write and organize tests for the Frost compiler.

Hspec is a popular testing framework for Haskell that allows developers to write human-readable specifications of their code's behavior. Hspec Discover is an extension that automatically finds and runs all test files in a project, simplifying test organization and execution.

To use Hspec with Hspec Discover in Frost:

1. Test files are placed in the test/ directory, mirroring the structure of the lib/ directory.

2. Each test file should end with Spec.hs, for example:

   test/
     Ast/
       Parser/
         ExprSpec.hs
         LiteralSpec.hs
     ...

3. A main test file (Spec.hs) in the test/ directory uses Hspec Discover:

   {-# OPTIONS_GHC -F -pgmF hspec-discover #-}

4. Individual test files use Hspec to describe and test specific components:

   module Ast.Parser.ExprSpec where
   
   import Test.Hspec
   import Ast.Parser.Expr
   
   spec :: Spec
   spec = do
     describe "parseExpr" $ do
       it "parses a simple addition" $ do
         -- Test code here

5. Run tests using cabal test, which will automatically discover and execute all test specs.

This setup allows for organized, maintainable, and easily extensible tests as the Frost compiler evolves.