testers.shfmt: init (#385939)

Author: philiptaron

doc/build-helpers/testers.chapter.md

@@ -165,6 +165,64 @@ testers.shellcheck {
 A derivation that runs `shellcheck` on the given script(s).
 The build will fail if `shellcheck` finds any issues.
 
+## `shfmt` {#tester-shfmt}
+
+Run files through `shfmt`, a shell script formatter, failing if any files are reformatted.
+
+:::{.example #ex-shfmt}
+# Run `testers.shfmt`
+
+A single script
+
+```nix
+testers.shfmt {
+  name = "script";
+  src = ./script.sh;
+}
+```
+
+Multiple files
+
+```nix
+let
+  inherit (lib) fileset;
+in
+testers.shfmt {
+  name = "nixbsd";
+  src = fileset.toSource {
+    root = ./.;
+    fileset = fileset.unions [
+      ./lib.sh
+      ./nixbsd-activate
+    ];
+  };
+}
+```
+
+:::
+
+### Inputs {#tester-shfmt-inputs}
+
+`name` (string)
+: The name of the test.
+  `name` is required because it massively improves traceability of test failures.
+  The name of the derivation produced by the tester is `shfmt-${name}`.
+
+`src` (path-like)
+: The path to the shell script(s) to check.
+  This can be a single file or a directory containing shell files.
+  All files in `src` will be checked, so you may want to provide `fileset`-based source instead of a whole directory.
+
+`indent` (integer, optional)
+: The number of spaces to use for indentation.
+  Defaults to `2`.
+  A value of `0` indents with tabs.
+
+### Return value {#tester-shfmt-return}
+
+A derivation that runs `shfmt` on the given script(s), producing an empty output upon success.
+The build will fail if `shfmt` reformats anything.
+
 ## `testVersion` {#tester-testVersion}
 
 Checks that the output from running a command contains the specified version string in it as a whole word.

doc/redirects.json

@@ -8,6 +8,9 @@
   "ex-build-helpers-extendMkDerivation": [
     "index.html#ex-build-helpers-extendMkDerivation"
   ],
+  "ex-shfmt": [
+    "index.html#ex-shfmt"
+  ],
   "ex-testBuildFailurePrime-doc-example": [
     "index.html#ex-testBuildFailurePrime-doc-example"
   ],
@@ -338,6 +341,15 @@
   "footnote-stdenv-find-inputs-location.__back.0": [
     "index.html#footnote-stdenv-find-inputs-location.__back.0"
   ],
+  "tester-shfmt": [
+    "index.html#tester-shfmt"
+  ],
+  "tester-shfmt-inputs": [
+    "index.html#tester-shfmt-inputs"
+  ],
+  "tester-shfmt-return": [
+    "index.html#tester-shfmt-return"
+  ],
   "tester-testBuildFailurePrime": [
     "index.html#tester-testBuildFailurePrime"
   ],

pkgs/build-support/testers/default.nix

@@ -194,4 +194,6 @@
   testMetaPkgConfig = callPackage ./testMetaPkgConfig/tester.nix { };
 
   shellcheck = callPackage ./shellcheck/tester.nix { };
+
+  shfmt = callPackage ./shfmt { };
 }

pkgs/build-support/testers/shfmt/default.nix

@@ -0,0 +1,29 @@
+{
+  lib,
+  shfmt,
+  stdenvNoCC,
+}:
+# See https://nixos.org/manual/nixpkgs/unstable/#tester-shfmt
+# or doc/build-helpers/testers.chapter.md
+{
+  name,
+  src,
+  indent ? 2,
+}:
+stdenvNoCC.mkDerivation (finalAttrs: {
+  __structuredAttrs = true;
+  strictDeps = true;
+  inherit src indent;
+  name = "shfmt-${name}";
+  dontUnpack = true; # Unpack phase tries to extract archive
+  nativeBuildInputs = [ shfmt ];
+  doCheck = true;
+  dontConfigure = true;
+  dontBuild = true;
+  checkPhase = ''
+    shfmt --diff --indent $indent --simplify "$src"
+  '';
+  installPhase = ''
+    touch "$out"
+  '';
+})

pkgs/build-support/testers/shfmt/src/indent2.sh

@@ -0,0 +1,3 @@
+hello() {
+  echo "hello"
+}

pkgs/build-support/testers/shfmt/tests.nix

@@ -0,0 +1,43 @@
+{ lib, testers }:
+lib.recurseIntoAttrs {
+  # Positive tests
+  indent2 = testers.shfmt {
+    name = "indent2";
+    indent = 2;
+    src = ./src/indent2.sh;
+  };
+  indent2Bin = testers.shfmt {
+    name = "indent2Bin";
+    indent = 2;
+    src = ./src;
+  };
+  # Negative tests
+  indent2With0 = testers.testBuildFailure' {
+    drv = testers.shfmt {
+      name = "indent2";
+      indent = 0;
+      src = ./src/indent2.sh;
+    };
+  };
+  indent2BinWith0 = testers.testBuildFailure' {
+    drv = testers.shfmt {
+      name = "indent2Bin";
+      indent = 0;
+      src = ./src;
+    };
+  };
+  indent2With4 = testers.testBuildFailure' {
+    drv = testers.shfmt {
+      name = "indent2";
+      indent = 4;
+      src = ./src/indent2.sh;
+    };
+  };
+  indent2BinWith4 = testers.testBuildFailure' {
+    drv = testers.shfmt {
+      name = "indent2Bin";
+      indent = 4;
+      src = ./src;
+    };
+  };
+}

pkgs/build-support/testers/test/default.nix

@@ -39,6 +39,8 @@ lib.recurseIntoAttrs {
 
   shellcheck = pkgs.callPackage ../shellcheck/tests.nix { };
 
+  shfmt = pkgs.callPackages ../shfmt/tests.nix { };
+
   runCommand = lib.recurseIntoAttrs {
     bork = pkgs.python3Packages.bork.tests.pytest-network;