pyroscope: address review feedback

pkgs/by-name/py/pyroscope/package.nix

@@ -1,7 +1,10 @@
 {
+  stdenv,
   buildGoModule,
   lib,
   fetchFromGitHub,
+  versionCheckHook,
+  installShellFiles,
   nix-update-script,
   ...
 }:
@@ -32,10 +35,25 @@ buildGoModule (finalAttrs: {
     "-X=github.com/grafana/pyroscope/pkg/util/build.BuildDate=1970-01-01T00:00:00Z"
   ];
 
+  # We're overriding the version in 'ldFlags', so we should check that the
+  # derivation 'version' string is found in 'pyroscope --version'.
+  nativeInstallCheckInputs = [ versionCheckHook ];
+  doInstallCheck = true;
+  versionCheckProgram = "${placeholder "out"}/bin/${finalAttrs.meta.mainProgram}";
+  versionCheckProgramArg = "--version";
+
+  nativeBuildInputs = [ installShellFiles ];
+  postInstall = lib.optionalString (stdenv.buildPlatform.canExecute stdenv.hostPlatform) ''
+    installShellCompletion --cmd pyroscope \
+      --bash <($out/bin/pyroscope completion bash) \
+      --fish <($out/bin/pyroscope completion fish) \
+      --zsh <($out/bin/pyroscope completion zsh)
+  '';
+
   passthru.updateScript = nix-update-script { };
 
   meta = {
-    description = "Continuous Profiling Platform. Debug performance issues down to a single line of code";
+    description = "Continuous profiling platform; debug performance issues down to a single line of code";
     homepage = "https://github.com/grafana/pyroscope";
     changelog = "https://github.com/grafana/pyroscope/blob/${finalAttrs.src.rev}/CHANGELOG.md";
     license = lib.licenses.agpl3Only;