graphql-engine/server/src-test/Hasura/GraphQL/Parser/MonadParseTest.hs
Samir Talwar eab4f75212 An ErrorMessage type, to encapsulate.
This introduces an `ErrorMessage` newtype which wraps `Text` in a manner which is designed to be easy to construct, and difficult to deconstruct.

It provides functionality similar to `Data.Text.Extended`, but designed _only_ for error messages. Error messages are constructed through `fromString`, concatenation, or the `toErrorValue` function, which is designed to be overridden for all meaningful domain types that might show up in an error message. Notably, there are not and should never be instances of `ToErrorValue` for `String`, `Text`, `Int`, etc. This is so that we correctly represent the value in a way that is specific to its type. For example, all `Name` values (from the _graphql-parser-hs_ library) are single-quoted now; no exceptions.

I have mostly had to add `instance ToErrorValue` for various backend types (and also add newtypes where necessary). Some of these are not strictly necessary for this changeset, as I had bigger aspirations when I started. These aspirations have been tempered by trying and failing twice.

As such, in this changeset, I have started by introducing this type to the `parseError` and `parseErrorWith` functions. In the future, I would like to extend this to the `QErr` record and the various `throwError` functions, but this is a much larger task and should probably be done in stages.

For now, `toErrorMessage` and `fromErrorMessage` are provided for conversion to and from `Text`, but the intent is to stop exporting these once all error messages are converted to the new type.

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/5018
GitOrigin-RevId: 84b37e238992e4312255a87ca44f41af65e2d89a
2022-07-18 20:27:06 +00:00

30 lines
1018 B
Haskell

module Hasura.GraphQL.Parser.MonadParseTest (spec) where
import Data.Aeson.Internal
import Hasura.Base.Error
import Hasura.Base.Error.TestInstances ()
import Hasura.Base.ErrorMessage
import Hasura.GraphQL.Parser.Class.Parse
import Hasura.GraphQL.Parser.Monad
import Hasura.Prelude
import Test.Hspec
runParse' :: Parse () -> Either QErr ()
runParse' = runParse @_ @()
errorMessage :: ErrorMessage
errorMessage = "oh no"
spec :: Spec
spec = do
describe "withKey" $ do
it "Path is empty when no keys added" $ do
let parser = parseError errorMessage
expected = (err400 ValidationFailed (fromErrorMessage errorMessage)) {qePath = mempty}
runParse' parser `shouldBe` Left expected
it "Path has two items in the order they were added" $ do
let parser = withKey (Key "dog") (withKey (Key "log") (parseError errorMessage))
expected = (err400 ValidationFailed (fromErrorMessage errorMessage)) {qePath = [Key "dog", Key "log"]}
runParse' parser `shouldBe` Left expected