fix --stdin behaviour to match the Rust version

[brianmcgee]

Describe the bug

See #274 for more info, but the short version is that --stdin doesn't work as it's supposed to.

[nifoc]

I don't think this is fixed, or maybe I'm running into a different issue?

Version 1:

$ treefmt --version
treefmt 0.6.1

$ cat home/config/nvim/after/ftplugin/elixir.fnl | treefmt elixir.fnl --stdin
[INFO ] running #fnlfmt
(let [lo vim.opt_local]
  (set lo.spell true)
  (set lo.textwidth 120)
  (set lo.colorcolumn :+1))

Version 2:

$ treefmt --version
treefmt v2.0.2

$ cat home/config/nvim/after/ftplugin/elixir.fnl | treefmt elixir.fnl --stdin
fnlfmt error:
File not found: _9bc10y_0w0000gn/T/1209928017.fnl

treefmt: error: formatting failure: formatter '/nix/store/ihkzf1njld48inl1kjsgdk1v61f1hqjx-fnlfmt-0.3.1/bin/fnlfmt' with options '[--fix]' failed to apply: exit status 1

Edit

Not related specifically to fnlfmt:

$ treefmt --version
treefmt v2.0.2

$ cat flake.nix | treefmt --stdin flake.nix
nixpkgs-fmt error:
No such file or directory (os error 2)

treefmt: error: formatting failure: formatter '/nix/store/0zgggwjqgxisg5ba8g902z18jkf580df-nixpkgs-fmt-1.3.0/bin/nixpkgs-fmt' with options '[]' failed to apply: exit status 1

[brianmcgee]

@nifoc 🤔 thanks for the test case; I think I have some time this afternoon to look at this.

[brianmcgee]

@nifoc in the meantime can you run your test command with -vv: cat flake.nix | treefmt --stdin -vv flake.nix

I just checked out the v2.0.2 branch and ran the following from the root directory without issue:

✦ ❯ cat flake.nix | nix run .# -- --config-file test/examples/nixpkgs.toml --stdin flake.nix
{
  description = "Treefmt: once CLI to format your repo";

  nixConfig = {
    extra-substituters = [ "https://numtide.cachix.org" ];
    extra-trusted-public-keys = [ "numtide.cachix.org-1:2ps1kLBUWjxIneOy1Ik6cQjb41X0iXVXeHigGmycPPE=" ];
  };

  inputs = {
    blueprint = {
      url = "github:numtide/blueprint";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    devshell = {
      url = "github:numtide/devshell";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    gomod2nix = {
      url = "github:nix-community/gomod2nix";
      inputs.nixpkgs.follows = "nixpkgs";
      inputs.flake-utils.follows = "devshell/flake-utils";
    };
    flake-compat.url = "github:nix-community/flake-compat";
    nix-filter.url = "github:numtide/nix-filter";
    nix-github-actions = {
      url = "github:nix-community/nix-github-actions";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
    treefmt-nix = {
      url = "github:numtide/treefmt-nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = inputs:
    let
      inherit (inputs.nixpkgs) lib;
    in
    inputs.blueprint
      {
        inherit inputs;
        prefix = "nix/";
        nixpkgs.config = {
          allowUnfreePredicate = pkg: builtins.elem (lib.getName pkg) [ "terraform" ];
        };
      }
    // {
      githubActions = inputs.nix-github-actions.lib.mkGithubMatrix {
        checks =
          lib.getAttrs [
            "x86_64-linux"
            "x86_64-darwin"
          ]
            inputs.self.checks;
      };
    };
}

[brianmcgee]

@nifoc and can you provide your treefmt.toml as well.

[nifoc]

Not sure if it's relevant, but I make use of treefmt using the flake-parts module and I'm on macOS.

I also tried treefmt without the flake-parts "wrapper" (but using the same config file) and ran into the same issue.

cat flake.nix | treefmt --stdin -vv flake.nix
DEBU format: config-file=/nix/store/p65hy55vr5pbhv765cp2j1zirs49phjp-treefmt.toml tree-root=/Users/daniel/.config/nixpkgs
DEBU format | nixpkgs-fmt: match: /var/folders/wf/l_vqfv6976qc30_9bc10y_0w0000gn/T/3014005140.nix
DEBU format | nixpkgs-fmt: executing: /nix/store/0zgggwjqgxisg5ba8g902z18jkf580df-nixpkgs-fmt-1.3.0/bin/nixpkgs-fmt _9bc10y_0w0000gn/T/3014005140.nix
nixpkgs-fmt error:
No such file or directory (os error 2)

treefmt: error: formatting failure: formatter '/nix/store/0zgggwjqgxisg5ba8g902z18jkf580df-nixpkgs-fmt-1.3.0/bin/nixpkgs-fmt' with options '[]' failed to apply: exit status 1

Config:

$ cat /nix/store/p65hy55vr5pbhv765cp2j1zirs49phjp-treefmt.toml
[formatter]
[formatter.fnlfmt]
command = "/nix/store/ihkzf1njld48inl1kjsgdk1v61f1hqjx-fnlfmt-0.3.1/bin/fnlfmt"
excludes = []
includes = ["*.fnl"]
options = ["--fix"]

[formatter.nixpkgs-fmt]
command = "/nix/store/0zgggwjqgxisg5ba8g902z18jkf580df-nixpkgs-fmt-1.3.0/bin/nixpkgs-fmt"
excludes = []
includes = ["*.nix"]
options = []

[formatter.shfmt]
command = "/nix/store/whzcdk13r9l10nbs24dbld7395vhma2v-shfmt-3.8.0/bin/shfmt"
excludes = []
includes = ["*.sh", "*.bash", "*.envrc"]
options = ["-i", "2", "-s", "-w"]

[formatter.yamlfmt]
command = "/nix/store/3k0q89mvqmn833vkchy4k45xk897sdva-yamlfmt-0.13.0/bin/yamlfmt"
excludes = []
includes = ["*.yaml", "*.yml"]
options = []

[global]
excludes = ["*.lock", "*.patch", ".gitignore", ".gitmodules", ".hgignore", ".svnignore"]

[brianmcgee]

The path that was matched:

DEBU format | nixpkgs-fmt: match: /var/folders/wf/l_vqfv6976qc30_9bc10y_0w0000gn/T/3014005140.nix

The same path passed to the formatter is truncated:

DEBU format | nixpkgs-fmt: executing: /nix/store/0zgggwjqgxisg5ba8g902z18jkf580df-nixpkgs-fmt-1.3.0/bin/nixpkgs-fmt _9bc10y_0w0000gn/T/3014005140.nix

I ran this on my mac:

❯ cat flake.nix | result/bin/treefmt --config-file test/examples/nixpkgs.toml  -stdin flake.nix -vv
DEBU format: config-file=/Users/brian/Development/com/github/numtide/treefmt/test/examples/nixpkgs.toml tree-root=/Users/brian/Development/com/github/numtide/treefmt/test/examples
DEBU format | nixpkgs-fmt[2]: match: /var/folders/3r/0x4fl3z97l3ffql__8xst2cm0000gn/T/3984232970.nix
DEBU format | deadnix[1]: match: /var/folders/3r/0x4fl3z97l3ffql__8xst2cm0000gn/T/3984232970.nix
DEBU format | deadnix[1]: executing: /nix/store/wlqykhn3yvq9hcn8sf1d2s34d732cjfy-devshell-dir/bin/deadnix --edit ../../../../../../../../../var/folders/3r/0x4fl3z97l3ffql__8xst2cm0000gn/T/3984232970.nix
INFO format | deadnix[1]: 1 files processed in 5.322125ms
DEBU format | nixpkgs-fmt[2]: executing: /nix/store/wlqykhn3yvq9hcn8sf1d2s34d732cjfy-devshell-dir/bin/nixpkgs-fmt ../../../../../../../../../var/folders/3r/0x4fl3z97l3ffql__8xst2cm0000gn/T/3984232970.nix
INFO format | nixpkgs-fmt[2]: 1 files processed in 5.374042ms
{
  description = "Treefmt: once CLI to format your repo";

  nixConfig = {
    extra-substituters = [ "https://numtide.cachix.org" ];
    extra-trusted-public-keys = [ "numtide.cachix.org-1:2ps1kLBUWjxIneOy1Ik6cQjb41X0iXVXeHigGmycPPE=" ];
  };

  inputs = {
    blueprint = {
      url = "github:numtide/blueprint";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    devshell = {
      url = "github:numtide/devshell";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    gomod2nix = {
      url = "github:nix-community/gomod2nix";
      inputs.nixpkgs.follows = "nixpkgs";
      inputs.flake-utils.follows = "devshell/flake-utils";
    };
    flake-compat.url = "github:nix-community/flake-compat";
    nix-filter.url = "github:numtide/nix-filter";
    nix-github-actions = {
      url = "github:nix-community/nix-github-actions";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
    treefmt-nix = {
      url = "github:numtide/treefmt-nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = inputs:
    let
      inherit (inputs.nixpkgs) lib;
    in
    inputs.blueprint
      {
        inherit inputs;
        prefix = "nix/";
        nixpkgs.config = {
          allowUnfreePredicate = pkg: builtins.elem (lib.getName pkg) [ "terraform" ];
        };
      }
    // {
      githubActions = inputs.nix-github-actions.lib.mkGithubMatrix {
        checks =
          lib.getAttrs [
            "x86_64-linux"
            "x86_64-darwin"
          ]
            inputs.self.checks;
      };
    };
}

It is able to resolve the relative path to the temp file, unlike in your example. 🤔

[brianmcgee]

@nifoc I'm pretty sure this is the culprit:

treefmt/walk/filesystem.go

Lines 22 to 29 in 65152cb

	relPathFn := func(path string) (string, error) {
	// quick optimisation for the majority of use cases
	// todo check that root is a prefix in path?
	if len(path) >= relPathOffset {
	return path[relPathOffset:], nil
	}
	return filepath.Rel(f.root, path)
	}

[brianmcgee]

@nifoc I have a fix inbound #348

You should be able to try it out by adding a treefmt flake input with url = github:numtide/treefmt/fix/relative-path-resolution and override the package option in the flake.parts module to point to inputs.treefmt.packages.${system}.treefmt.

[nifoc]

Sorry for not being able to respond earlier.

It works for me, too. Thank you for the very quick fix!