From bbe1d0cd5612109ec87e3a2c8ed4ae508e90fade Mon Sep 17 00:00:00 2001
From: Vinzent Steinberg <Vinzent.Steinberg@gmail.com>
Date: Sat, 10 Apr 2021 00:48:58 -0300
Subject: [PATCH 1/3] Improve error message for `cargo test`

There is a custom compiler error, hinting that the "debug", "compare"
and "rand" feature are required for compiling and running the tests.
However, this error was not displayed when running `cargo test` due to
other compilation errors taking precedence.

This is now avoided by just not compiling the integration tests when the
necessary features are not enabled.
---
 tests/lib.rs | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/tests/lib.rs b/tests/lib.rs
index add7a468..8ee85f07 100644
--- a/tests/lib.rs
+++ b/tests/lib.rs
@@ -1,8 +1,4 @@
-#[cfg(any(
-    not(feature = "debug"),
-    not(feature = "compare"),
-    not(feature = "rand")
-))]
+#[cfg(not(all(feature = "debug", feature = "compare", feature = "rand")))]
 compile_error!(
     "Please enable the `debug`, `compare`, and `rand` features in order to compile and run the tests.
      Example: `cargo test --features debug,compare,rand`"
@@ -10,18 +6,25 @@ compile_error!(
 
 #[cfg(feature = "abomonation-serialize")]
 extern crate abomonation;
+#[cfg(all(feature = "debug", feature = "compare", feature = "rand"))]
 #[macro_use]
 extern crate approx;
 extern crate nalgebra as na;
 extern crate num_traits as num;
+#[cfg(feature = "rand")]
 extern crate rand_package as rand;
 
+#[cfg(all(feature = "debug", feature = "compare", feature = "rand"))]
 mod core;
+#[cfg(all(feature = "debug", feature = "compare", feature = "rand"))]
 mod geometry;
+#[cfg(all(feature = "debug", feature = "compare", feature = "rand"))]
 mod linalg;
 
+#[cfg(all(feature = "debug", feature = "compare", feature = "rand"))]
 #[cfg(feature = "proptest-support")]
 mod proptest;
 
+//#[cfg(all(feature = "debug", feature = "compare", feature = "rand"))]
 //#[cfg(feature = "sparse")]
 //mod sparse;

From df33dec457d57a6f910ab7c0429ecf95fc14fb13 Mon Sep 17 00:00:00 2001
From: Vinzent Steinberg <Vinzent.Steinberg@gmail.com>
Date: Sat, 10 Apr 2021 00:52:54 -0300
Subject: [PATCH 2/3] Make "compare" a required feature for the `matrixcompare`
 example

This avoids distracting error messages when running `cargo test` and
gives a better error when trying to run the example without the required
feature.
---
 Cargo.toml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Cargo.toml b/Cargo.toml
index d9418a88..39dbb555 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -92,6 +92,10 @@ itertools = "0.10"
 [workspace]
 members = [ "nalgebra-lapack", "nalgebra-glm", "nalgebra-sparse" ]
 
+[[example]]
+name = "matrixcompare"
+required-features = ["compare"]
+
 [[bench]]
 name = "nalgebra_bench"
 harness = false

From 260ee54288a70d9ff388f7c2b57539b166719c45 Mon Sep 17 00:00:00 2001
From: Vinzent Steinberg <Vinzent.Steinberg@gmail.com>
Date: Sat, 10 Apr 2021 01:00:12 -0300
Subject: [PATCH 3/3] Disable some tests if "rand" feature is disabled

This avoids some misleading errors for `cargo test`.
---
 src/geometry/quaternion_construction.rs | 1 +
 src/linalg/symmetric_eigen.rs           | 1 +
 2 files changed, 2 insertions(+)

diff --git a/src/geometry/quaternion_construction.rs b/src/geometry/quaternion_construction.rs
index 89911b91..50807907 100644
--- a/src/geometry/quaternion_construction.rs
+++ b/src/geometry/quaternion_construction.rs
@@ -891,6 +891,7 @@ where
 }
 
 #[cfg(test)]
+#[cfg(feature = "rand")]
 mod tests {
     extern crate rand_xorshift;
     use super::*;
diff --git a/src/linalg/symmetric_eigen.rs b/src/linalg/symmetric_eigen.rs
index 64d3515a..d30c2f80 100644
--- a/src/linalg/symmetric_eigen.rs
+++ b/src/linalg/symmetric_eigen.rs
@@ -337,6 +337,7 @@ mod test {
         }
     }
 
+    #[cfg(feature = "rand")]
     #[test]
     fn wilkinson_shift_random() {
         for _ in 0..1000 {