13 files changed, 174 insertions, 38 deletions
diff --git a/doc/languages-frameworks/rust.section.md b/doc/languages-frameworks/rust.section.md
index cec3373cbee6..7e5cff8ff607 100644
--- a/doc/languages-frameworks/rust.section.md
+++ b/doc/languages-frameworks/rust.section.md
@@ -75,6 +75,72 @@ pkgs.rustPlatform.buildRustPackage {
 }
 ```
 
+### Running package tests
+
+When using `buildRustPackage`, the `checkPhase` is enabled by default and runs
+`cargo test` on the package to build. To make sure that we don't compile the
+sources twice and to actually test the artifacts that will be used at runtime, 
+the tests will be ran in the `release` mode by default.
+
+However, in some cases the test-suite of a package doesn't work properly in the
+`release` mode. For these situations, the mode for `checkPhase` can be changed like
+so:
+
+```nix
+rustPlatform.buildRustPackage {
+  /* ... */
+  checkType = "debug";
+}
+```
+
+Please note that the code will be compiled twice here: once in `release` mode
+for the `buildPhase`, and again in `debug` mode for the `checkPhase`.
+
+#### Tests relying on the structure of the `target/` directory
+
+Some tests may rely on the structure of the `target/` directory. Those tests
+are likely to fail because we use `cargo --target` during the build. This means that
+the artifacts
+[are stored in `target/<architecture>/release/`](https://doc.rust-lang.org/cargo/guide/build-cache.html),
+rather than in `target/release/`.
+
+This can only be worked around by patching the affected tests accordingly.
+
+#### Disabling package-tests
+
+In some instances, it may be necessary to disable testing altogether (with `doCheck = false;`):
+
+* If no tests exist -- the `checkPhase` should be explicitly disabled to skip
+  unnecessary build steps to speed up the build.
+* If tests are highly impure (e.g. due to network usage).
+
+There will obviously be some corner-cases not listed above where it's sensible to disable tests.
+The above are just guidelines, and exceptions may be granted on a case-by-case basis.
+
+However, please check if it's possible to disable a problematic subset of the
+test suite and leave a comment explaining your reasoning.
+
+### Building a package in `debug` mode
+
+By default, `buildRustPackage` will use `release` mode for builds. If a package
+should be built in `debug` mode, it can be configured like so:
+
+```nix
+rustPlatform.buildRustPackage {
+  /* ... */
+  buildType = "debug";
+}
+```
+
+In this scenario, the `checkPhase` will be ran in `debug` mode as well.
+
+### Custom `build`/`install`-procedures
+
+Some packages may use custom scripts for building/installing, e.g. with a `Makefile`.
+In these cases, it's recommended to override the `buildPhase`/`installPhase`/`checkPhase`.
+
+Otherwise, some steps may fail because of the modified directory structure of `target/`.
+
 ## Compiling Rust crates using Nix instead of Cargo
 
 ### Simple operation
diff --git a/nixos/doc/manual/release-notes/rl-2009.xml b/nixos/doc/manual/release-notes/rl-2009.xml
index 428aeec23415..c65be35bea50 100644
--- a/nixos/doc/manual/release-notes/rl-2009.xml
+++ b/nixos/doc/manual/release-notes/rl-2009.xml
@@ -474,9 +474,21 @@ systemd.services.nginx.serviceConfig.ReadWritePaths = [ "/var/www" ];
     </para>
    </listitem>
    <listitem>
-   <para>
-     The default output of <literal>buildGoPackage</literal> is now <literal>$out</literal> instead of <literal>$bin</literal>.
-   </para>
+    <para>
+      The default output of <literal>buildGoPackage</literal> is now <literal>$out</literal> instead of <literal>$bin</literal>.
+    </para>
+   </listitem>
+   <listitem>
+    <para>
+     Packages built using <literal>buildRustPackage</literal> now use <literal>release</literal>
+     mode for the <literal>checkPhase</literal> by default.
+    </para>
+    <para>
+     Please note that Rust packages utilizing a custom build/install procedure
+     (e.g. by using a <filename>Makefile</filename>) or test suites that rely on the
+     structure of the <filename>target/</filename> directory may break due to those assumptions.
+     For further information, please read the Rust section in the Nixpkgs manual.
+    </para>
    </listitem>
    <listitem>
    <para>
diff --git a/pkgs/applications/editors/neovim/gnvim/default.nix b/pkgs/applications/editors/neovim/gnvim/default.nix
index e9f42d2b9b5e..3693ff322338 100644
--- a/pkgs/applications/editors/neovim/gnvim/default.nix
+++ b/pkgs/applications/editors/neovim/gnvim/default.nix
@@ -33,6 +33,10 @@ rustPlatform.buildRustPackage rec {
     EOF
   '';
 
+  buildPhase = ''
+    make build
+  '';
+
   installPhase = ''
     make install PREFIX="${placeholder "out"}"
   '';
diff --git a/pkgs/applications/networking/nym/default.nix b/pkgs/applications/networking/nym/default.nix
index 6bb86c016ba3..1ff449eab0cc 100644
--- a/pkgs/applications/networking/nym/default.nix
+++ b/pkgs/applications/networking/nym/default.nix
@@ -24,6 +24,8 @@ rustPlatform.buildRustPackage rec {
 
   buildInputs = [ openssl ];
 
+  checkType = "debug";
+
   /*
   Nym's test presence::converting_mixnode_presence_into_topology_mixnode::it_returns_resolved_ip_on_resolvable_hostname tries to resolve nymtech.net.
   Since there is no external DNS resolution available in the build sandbox, we point cargo and its children (that's what we remove the 'unsetenv' call for) to a hosts file in which we statically resolve nymtech.net.
diff --git a/pkgs/build-support/rust/default.nix b/pkgs/build-support/rust/default.nix
index a6b47930c274..d3e13b913f38 100644
--- a/pkgs/build-support/rust/default.nix
+++ b/pkgs/build-support/rust/default.nix
@@ -28,6 +28,13 @@
 , meta ? {}
 , target ? null
 , cargoVendorDir ? null
+, checkType ? buildType
+
+# Needed to `pushd`/`popd` into a subdir of a tarball if this subdir
+# contains a Cargo.toml, but isn't part of a workspace (which is e.g. the
+# case for `rustfmt`/etc from the `rust-sources).
+# Otherwise, everything from the tarball would've been built/tested.
+, buildAndTestSubdir ? null
 , ... } @ args:
 
 assert cargoVendorDir == null -> cargoSha256 != "unset";
@@ -161,6 +168,7 @@ stdenv.mkDerivation (args // {
   '';
 
   buildPhase = with builtins; args.buildPhase or ''
+    ${stdenv.lib.optionalString (buildAndTestSubdir != null) "pushd ${buildAndTestSubdir}"}
     runHook preBuild
 
     (
@@ -176,22 +184,29 @@ stdenv.mkDerivation (args // {
         --frozen ${concatStringsSep " " cargoBuildFlags}
     )
 
-    # rename the output dir to a architecture independent one
-    mapfile -t targets < <(find "$NIX_BUILD_TOP" -type d | grep '${releaseDir}$')
-    for target in "''${targets[@]}"; do
-      rm -rf "$target/../../${buildType}"
-      ln -srf "$target" "$target/../../"
-    done
-
     runHook postBuild
+
+    ${stdenv.lib.optionalString (buildAndTestSubdir != null) "popd"}
+
+    # This needs to be done after postBuild: packages like `cargo` do a pushd/popd in
+    # the pre/postBuild-hooks that need to be taken into account before gathering
+    # all binaries to install.
+    bins=$(find $releaseDir \
+      -maxdepth 1 \
+      -type f \
+      -executable ! \( -regex ".*\.\(so.[0-9.]+\|so\|a\|dylib\)" \))
   '';
 
-  checkPhase = args.checkPhase or ''
+  checkPhase = args.checkPhase or (let
+    argstr = "${stdenv.lib.optionalString (checkType == "release") "--release"} --target ${rustTarget} --frozen";
+  in ''
+    ${stdenv.lib.optionalString (buildAndTestSubdir != null) "pushd ${buildAndTestSubdir}"}
     runHook preCheck
-    echo "Running cargo cargo test -- ''${checkFlags} ''${checkFlagsArray+''${checkFlagsArray[@]}}"
-    cargo test -- ''${checkFlags} ''${checkFlagsArray+"''${checkFlagsArray[@]}"}
+    echo "Running cargo test ${argstr} -- ''${checkFlags} ''${checkFlagsArray+''${checkFlagsArray[@]}}"
+    cargo test ${argstr} -- ''${checkFlags} ''${checkFlagsArray+"''${checkFlagsArray[@]}"}
     runHook postCheck
-  '';
+    ${stdenv.lib.optionalString (buildAndTestSubdir != null) "popd"}
+  '');
 
   doCheck = args.doCheck or true;
 
@@ -201,13 +216,16 @@ stdenv.mkDerivation (args // {
 
   installPhase = args.installPhase or ''
     runHook preInstall
+
+    # rename the output dir to a architecture independent one
+    mapfile -t targets < <(find "$NIX_BUILD_TOP" -type d | grep '${releaseDir}$')
+    for target in "''${targets[@]}"; do
+      rm -rf "$target/../../${buildType}"
+      ln -srf "$target" "$target/../../"
+    done
     mkdir -p $out/bin $out/lib
 
-    find $releaseDir \
-      -maxdepth 1 \
-      -type f \
-      -executable ! \( -regex ".*\.\(so.[0-9.]+\|so\|a\|dylib\)" \) \
-      -print0 | xargs -r -0 cp -t $out/bin
+    xargs -r cp -t $out/bin <<< $bins
     find $releaseDir \
       -maxdepth 1 \
       -regex ".*\.\(so.[0-9.]+\|so\|a\|dylib\)" \
diff --git a/pkgs/development/compilers/rust/cargo.nix b/pkgs/development/compilers/rust/cargo.nix
index 65614b9480e7..dfea7f6c8ef6 100644
--- a/pkgs/development/compilers/rust/cargo.nix
+++ b/pkgs/development/compilers/rust/cargo.nix
@@ -9,8 +9,7 @@ rustPlatform.buildRustPackage {
 
   # the rust source tarball already has all the dependencies vendored, no need to fetch them again
   cargoVendorDir = "vendor";
-  preBuild = "pushd src/tools/cargo";
-  postBuild = "popd";
+  buildAndTestSubdir = "src/tools/cargo";
 
   passthru.rustc = rustc;
 
diff --git a/pkgs/development/compilers/rust/clippy.nix b/pkgs/development/compilers/rust/clippy.nix
index 4857b587847e..0546ad9bac1a 100644
--- a/pkgs/development/compilers/rust/clippy.nix
+++ b/pkgs/development/compilers/rust/clippy.nix
@@ -5,8 +5,7 @@ rustPlatform.buildRustPackage {
 
   # the rust source tarball already has all the dependencies vendored, no need to fetch them again
   cargoVendorDir = "vendor";
-  preBuild = "pushd src/tools/clippy";
-  postBuild = "popd";
+  buildAndTestSubdir = "src/tools/clippy";
 
   # changes hash of vendor directory otherwise
   dontUpdateAutotoolsGnuConfigScripts = true;
diff --git a/pkgs/development/compilers/rust/rls/default.nix b/pkgs/development/compilers/rust/rls/default.nix
index 4cf507fbf5c7..a050be7c2bfd 100644
--- a/pkgs/development/compilers/rust/rls/default.nix
+++ b/pkgs/development/compilers/rust/rls/default.nix
@@ -10,8 +10,9 @@ rustPlatform.buildRustPackage {
   dontUpdateAutotoolsGnuConfigScripts = true;
 
   cargoVendorDir = "vendor";
+  buildAndTestSubdir = "src/tools/rls";
+
   preBuild = ''
-    pushd src/tools/rls
     # client tests are flaky
     rm tests/client.rs
   '';
@@ -28,8 +29,6 @@ rustPlatform.buildRustPackage {
 
   doCheck = true;
 
-  preInstall = "popd";
-
   doInstallCheck = true;
   installCheckPhase = ''
     $out/bin/rls --version
diff --git a/pkgs/development/compilers/rust/rustfmt.nix b/pkgs/development/compilers/rust/rustfmt.nix
index f8ed0bce2e0d..66a18f40ad42 100644
--- a/pkgs/development/compilers/rust/rustfmt.nix
+++ b/pkgs/development/compilers/rust/rustfmt.nix
@@ -6,8 +6,7 @@ rustPlatform.buildRustPackage rec {
 
   # the rust source tarball already has all the dependencies vendored, no need to fetch them again
   cargoVendorDir = "vendor";
-  preBuild = "pushd src/tools/rustfmt";
-  preInstall = "popd";
+  buildAndTestSubdir = "src/tools/rustfmt";
 
   # changes hash of vendor directory otherwise
   dontUpdateAutotoolsGnuConfigScripts = true;
@@ -17,12 +16,6 @@ rustPlatform.buildRustPackage rec {
   # As of 1.0.0 and rustc 1.30 rustfmt requires a nightly compiler
   RUSTC_BOOTSTRAP = 1;
 
-  # we run tests in debug mode so tests look for a debug build of
-  # rustfmt. Anyway this adds nearly no compilation time.
-  preCheck = ''
-    cargo build
-  '';
-
   meta = with stdenv.lib; {
     description = "A tool for formatting Rust code according to style guidelines";
     homepage = "https://github.com/rust-lang-nursery/rustfmt";
diff --git a/pkgs/development/tools/rust/rust-analyzer/generic.nix b/pkgs/development/tools/rust/rust-analyzer/generic.nix
index de755ec17ff5..ae6ad80cdd9a 100644
--- a/pkgs/development/tools/rust/rust-analyzer/generic.nix
+++ b/pkgs/development/tools/rust/rust-analyzer/generic.nix
@@ -15,9 +15,7 @@ rustPlatform.buildRustPackage {
     inherit rev sha256;
   };
 
-  preBuild = "pushd crates/rust-analyzer";
-  # Do not checking other crates in checkPhase.
-  preInstall = "popd";
+  buildAndTestSubdir = "crates/rust-analyzer";
 
   cargoBuildFlags = lib.optional useJemalloc "--features=jemalloc";
 
diff --git a/pkgs/tools/package-management/cargo-deb/default.nix b/pkgs/tools/package-management/cargo-deb/default.nix
index c6e8b4803ccf..96ef0eef8c5a 100644
--- a/pkgs/tools/package-management/cargo-deb/default.nix
+++ b/pkgs/tools/package-management/cargo-deb/default.nix
@@ -2,7 +2,9 @@
 , lib
 , fetchFromGitHub
 , rustPlatform
-, Security }:
+, rust
+, Security
+}:
 
 rustPlatform.buildRustPackage rec {
   pname = "cargo-deb";
@@ -19,6 +21,13 @@ rustPlatform.buildRustPackage rec {
 
   cargoSha256 = "1vqnnqn6rzkdi239bh3lk7gaxr7w6v3c4ws4ya1ah04g6v9hkzlw";
 
+  checkType = "debug";
+
+  preCheck = ''
+    substituteInPlace tests/command.rs \
+      --replace 'target/debug' "target/${rust.toRustTarget stdenv.buildPlatform}/debug"
+  '';
+
   meta = with lib; {
     description = "Generate Debian packages from information in Cargo.toml";
     homepage = "https://github.com/mmstick/cargo-deb";
diff --git a/pkgs/tools/security/ripasso/cursive.nix b/pkgs/tools/security/ripasso/cursive.nix
index c8a55d3f397f..29229bff0028 100644
--- a/pkgs/tools/security/ripasso/cursive.nix
+++ b/pkgs/tools/security/ripasso/cursive.nix
@@ -12,6 +12,8 @@ buildRustPackage rec {
     sha256 = "164da20j727p8l7hh37j2r8pai9sj402nhswvg0nrlgj53nr6083";
   };
 
+  patches = [ ./fix-tests.patch ];
+
   cargoSha256 = "1wpn67v0xmxhn1dgzhh1pwz1yc3cizmfxhpb7qv9b27ynx4486ji";
 
   cargoBuildFlags = [ "-p ripasso-cursive -p ripasso-man" ];
diff --git a/pkgs/tools/security/ripasso/fix-tests.patch b/pkgs/tools/security/ripasso/fix-tests.patch
new file mode 100644
index 000000000000..433ff933b1f7
--- /dev/null
+++ b/pkgs/tools/security/ripasso/fix-tests.patch
@@ -0,0 +1,35 @@
+diff --git a/src/pass/test.rs b/src/pass/test.rs
+index c980a2f..2e6c8cc 100644
+--- a/src/pass/test.rs
++++ b/src/pass/test.rs
+@@ -56,6 +56,7 @@ fn populate_password_list_small_repo() {
+     base_path.pop();
+     base_path.pop();
+     base_path.pop();
++    base_path.pop();
+     base_path.push("testres");
+ 
+     let mut password_dir: PathBuf = base_path.clone();
+@@ -84,6 +85,7 @@ fn populate_password_list_repo_with_deleted_files() {
+     base_path.pop();
+     base_path.pop();
+     base_path.pop();
++    base_path.pop();
+     base_path.push("testres");
+ 
+     let mut password_dir: PathBuf = base_path.clone();
+@@ -112,6 +114,7 @@ fn populate_password_list_directory_without_git() {
+     base_path.pop();
+     base_path.pop();
+     base_path.pop();
++    base_path.pop();
+     base_path.push("testres");
+ 
+     let mut password_dir: PathBuf = base_path.clone();
+@@ -149,4 +152,4 @@ fn parse_signing_keys_empty() {
+     let result = PasswordStore::parse_signing_keys(&None).unwrap();
+ 
+     assert_eq!(result.len(), 0);
+-}
+\ No newline at end of file
++}