Merge pull request #231483 from hacker1024/feature/flutter-on-dart

If the upstream source is missing a `pubspec.lock` file, you'll have to vendor one and specify it using `pubspecLockFile`. If it is needed, one will be generated for you and printed when attempting to build the derivation.

The `depsListFile` must always be provided when packaging in Nixpkgs. It will be generated and printed if the derivation is attempted to be built without one. Alternatively, `autoDepsList` may be set to `true` only when outside of Nixpkgs, as it relies on import-from-derivation.

The `dart` commands run can be overridden through `pubGetScript` and `dartCompileCommand`, you can also add flags using `dartCompileFlags` or `dartJitFlags`.

Dart supports multiple [outputs types](https://dart.dev/tools/dart-compile#types-of-output), you can choose between them using `dartOutputType` (defaults to `exe`). If you want to override the binaries path or the source path they come from, you can use `dartEntryPoints`. Outputs that require a runtime will automatically be wrapped with the relevant runtime (`dartaotruntime` for `aot-snapshot`, `dart run` for `jit-snapshot` and `kernel`, `node` for `js`), this can be overridden through `dartRuntimeCommand`.

  };

  pubspecLockFile = ./pubspec.lock;

  depsListFile = ./deps.json;

  vendorHash = "sha256-Atm7zfnDambN/BmmUf4BG0yUz/y6xWzf0reDw3Ad41s=";

}

```

The function `buildFlutterApplication` builds Flutter applications.

The deps.json file must always be provided when packaging in Nixpkgs. It will be generated and printed if the derivation is attempted to be built without one. Alternatively, `autoDepsList` may be set to `true` when outside of Nixpkgs, as it relies on import-from-derivation.

A `pubspec.lock` file must be available. See the [Dart documentation](#ssec-dart-applications) for more details.

See the [Dart documentation](#ssec-dart-applications) for more details on required files and arguments.

```nix

{  flutter, fetchFromGitHub }:

{ lib, stdenv, fetchDartDeps, runCommand, writeText, dartHooks, makeWrapper, dart, cacert, nodejs, darwin }:

{ lib, stdenv, callPackage, fetchDartDeps, runCommand, writeText, dartHooks, makeWrapper, dart, cacert, nodejs, darwin, jq }:

{ pubGetScript ? "dart pub get"

{ sdkSetupScript ? ""

, pubGetScript ? "dart pub get"

  # Output type to produce. Can be any kind supported by dart

  # https://dart.dev/tools/dart-compile#types-of-output

, dartEntryPoints ? null

  # Used when wrapping aot, jit, kernel, and js builds.

  # Set to null to disable wrapping.

, dartRuntimeCommand ?

    if dartOutputType == "aot-snapshot" then "${dart}/bin/dartaotruntime"

, dartRuntimeCommand ? if dartOutputType == "aot-snapshot" then "${dart}/bin/dartaotruntime"

  else if (dartOutputType == "jit-snapshot" || dartOutputType == "kernel") then "${dart}/bin/dart"

  else if dartOutputType == "js" then "${nodejs}/bin/node"

  else null

, runtimeDependencies ? [ ]

, extraWrapProgramArgs ? ""

, customPackageOverrides ? { }

, autoDepsList ? false

, depsListFile ? null

, pubspecLockFile ? null

, vendorHash ? ""

, ...

    '';

  }) {

    buildDrvArgs = args;

    inherit pubGetScript vendorHash pubspecLockFile;

    inherit sdkSetupScript pubGetScript vendorHash pubspecLockFile;

  };

  inherit (dartHooks.override { inherit dart; }) dartConfigHook dartBuildHook dartInstallHook;

in

assert !(builtins.isString dartOutputType && dartOutputType != "") ->

  throw "dartOutputType must be a non-empty string";

stdenv.mkDerivation (args // {

  inherit pubGetScript dartCompileCommand dartOutputType dartRuntimeCommand

    dartCompileFlags dartJitFlags;

  inherit (dartHooks.override { inherit dart; }) dartConfigHook dartBuildHook dartInstallHook dartFixupHook;

  baseDerivation = stdenv.mkDerivation (finalAttrs: args // {

    inherit sdkSetupScript pubGetScript dartCompileCommand dartOutputType

      dartRuntimeCommand dartCompileFlags dartJitFlags runtimeDependencies;

    dartEntryPoints =

      if (dartEntryPoints != null)

      then writeText "entrypoints.json" (builtins.toJSON dartEntryPoints)

      else null;

    runtimeDependencyLibraryPath = lib.makeLibraryPath finalAttrs.runtimeDependencies;

    nativeBuildInputs = (args.nativeBuildInputs or [ ]) ++ [

      dart

      dartDeps

      dartConfigHook

      dartBuildHook

      dartInstallHook

      dartFixupHook

      makeWrapper

      jq

    ] ++ lib.optionals stdenv.isDarwin [

      darwin.sigtool

    ];

    preUnpack = ''

      ${lib.optionalString (!autoDepsList) ''

        if ! { [ '${lib.boolToString (depsListFile != null)}' = 'true' ] ${lib.optionalString (depsListFile != null) "&& cmp -s <(jq -Sc . '${depsListFile}') <(jq -Sc . '${finalAttrs.passthru.dartDeps.depsListFile}')"}; }; then

          echo 1>&2 -e '\nThe dependency list file was either not given or differs from the expected result.' \

                      '\nPlease choose one of the following solutions:' \

                      '\n - Duplicate the following file and pass it to the depsListFile argument.' \

                      '\n   ${finalAttrs.passthru.dartDeps.depsListFile}' \

                      '\n - Set autoDepsList to true (not supported by Hydra or permitted in Nixpkgs)'.

          exit 1

        fi

      ''}

      ${args.preUnpack or ""}

    '';

    # When stripping, it seems some ELF information is lost and the dart VM cli

    # runs instead of the expected program. Don't strip if it's an exe output.

    dontStrip = args.dontStrip or (dartOutputType == "exe");

    passthru = { inherit dartDeps; } // (args.passthru or { });

    meta = (args.meta or { }) // { platforms = args.meta.platforms or dart.meta.platforms; };

  });

  packageOverrideRepository = (callPackage ../../../development/compilers/dart/package-overrides { }) // customPackageOverrides;

  productPackages = builtins.filter (package: package.kind != "dev")

    (if autoDepsList

    then lib.importJSON dartDeps.depsListFile

    else

      if depsListFile == null

      then [ ]

      else lib.importJSON depsListFile);

in

assert !(builtins.isString dartOutputType && dartOutputType != "") ->

throw "dartOutputType must be a non-empty string";

builtins.foldl'

  (prev: package:

  if packageOverrideRepository ? ${package.name}

  then

    prev.overrideAttrs

      (packageOverrideRepository.${package.name} {

        inherit (package)

          name

          version

          kind

          source

          dependencies;

      })

  else prev)

  baseDerivation

  productPackages

dartConfigHook() {

    echo "Executing dartConfigHook"

    echo "Setting up SDK"

    eval "$sdkSetupScript"

    echo "Installing dependencies"

    eval doPubGet "$pubGetScript" --offline

# shellcheck shell=bash

dartFixupHook() {

    echo "Executing dartFixupHook"

    declare -a wrapProgramArgs

    # Add runtime library dependencies to the LD_LIBRARY_PATH.

    # For some reason, the RUNPATH of the executable is not used to load dynamic libraries in dart:ffi with DynamicLibrary.open().

    #

    # This could alternatively be fixed with patchelf --add-needed, but this would cause all the libraries to be opened immediately,

    # which is not what application authors expect.

    echo "$runtimeDependencyLibraryPath"

    if [[ ! -z "$runtimeDependencyLibraryPath" ]]; then

        wrapProgramArgs+=(--suffix LD_LIBRARY_PATH : \"$runtimeDependencyLibraryPath\")

    fi

    if [[ ! -z "$extraWrapProgramArgs" ]]; then

        wrapProgramArgs+=("$extraWrapProgramArgs")

    fi

    if [ ${#wrapProgramArgs[@]} -ne 0 ]; then

        for f in "$out"/bin/*; do

            echo "Wrapping $f..."

            eval "wrapProgram \"$f\" ${wrapProgramArgs[@]}"

        done

    fi

    echo "Finished dartFixupHook"

}

postFixupHooks+=(dartFixupHook)

  dartInstallHook = makeSetupHook {

    name = "dart-install-hook";

  } ./dart-install-hook.sh;

  dartFixupHook = makeSetupHook {

    name = "dart-fixup-hook";

  } ./dart-fixup-hook.sh;

}