fix: Inspect implementation for Absinthe.Resolution on Elixir 1.19+

[dorian-marchal]

Related issue: #1403

Problem

On Elixir 1.19+, inspecting an Absinthe.Resolution struct crashes with:

** (FunctionClauseError) no function clause matching in Inspect.Algebra.concat/2

This is caused by a breaking change in Elixir 1.19 where Inspect.List.inspect/2 now returns a tuple {doc, opts} instead of just a document. The current implementation passes this tuple directly to concat/1, which expects a valid document.

Solution

Replace Inspect.List.inspect(opts) with Inspect.Algebra.to_doc(opts).

Changes

• lib/absinthe/resolution.ex: Updated the Inspect protocol implementation to use to_doc/2 instead of Inspect.List.inspect/2

Fixes #1403

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Co-authored by Augment Code

[cschiewek]

@dorian-marchal Can you please address the CI failures. I'm happy to review and potentially merge once CI passes.

[dorian-marchal]

@cschiewek thanks, not sure how to fix this: https://github.com/absinthe-graphql/absinthe/actions/runs/20960390649/job/60235699604?pr=1409

Run mix dialyzer
Finding suitable PLTs
Checking PLT...
[:absinthe, :crypto, :dataloader, :decimal, :elixir, :ex_unit, :kernel, :logger, :mix, :nimble_parsec, :opentelemetry_process_propagator, :stdlib, :telemetry]
PLT is up to date!
No :ignore_warnings opt specified in mix.exs. Using default: .dialyzer_ignore.exs.

Starting Dialyzer
[
  check_plt: false,
  init_plt: ~c"/home/runner/work/absinthe/absinthe/priv/plts/project.plt",
  files: [~c"/home/runner/work/absinthe/absinthe/_build/test/lib/absinthe/ebin/Elixir.Absinthe.Middleware.PassParent.beam",
   ~c"/home/runner/work/absinthe/absinthe/_build/test/lib/absinthe/ebin/Elixir.Inspect.Absinthe.Blueprint.Schema.ObjectTypeDefinition.beam",
   ~c"/home/runner/work/absinthe/absinthe/_build/test/lib/absinthe/ebin/Elixir.Absinthe.Phase.Document.Complexity.Analysis.beam",
   ~c"/home/runner/work/absinthe/absinthe/_build/test/lib/absinthe/ebin/Elixir.Absinthe.Fixtures.Directive.TestSchemaArgDescriptionKeyword.Compiled.beam",
   ~c"/home/runner/work/absinthe/absinthe/_build/test/lib/absinthe/ebin/Elixir.Absinthe.Utils.Render.beam",
   ...],
  warnings: [:unknown]
]
:dialyzer.run error: Old PLT file /home/runner/work/absinthe/absinthe/priv/plts/project.plt

Halting VM with exit status 1
Error: Process completed with exit code 1.

[dorian-marchal]

Hey @cschiewek,

I looked into the Dialyzer failure and it seems unrelated to my changes: the error Old PLT file usually means the cached PLT was built with a different Erlang/OTP version than what's running now.

Would you be able to clear the Actions cache for the PLT files?

Edit: here is an other merge request with the same CI fail but no code change: #1410