From b63743645f2870ccac9ee3d727dc6ef036c18689 Mon Sep 17 00:00:00 2001
From: Tyler Veness <calcmogul@gmail.com>
Date: Sat, 15 Nov 2025 17:04:09 -0800
Subject: [PATCH] [wpimath] Only print Sleipnir diagnostics on test failure
 (#8382)

Bazel and CMake's CTest already do this by default since they run tests
in parallel, but Gradle doesn't.
---
 .../cpp/optimization/NonlinearProblemTest.cpp | 38 ++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/wpimath/src/test/native/cpp/optimization/NonlinearProblemTest.cpp b/wpimath/src/test/native/cpp/optimization/NonlinearProblemTest.cpp
index 60ccf2562c..eb1f0c345b 100644
--- a/wpimath/src/test/native/cpp/optimization/NonlinearProblemTest.cpp
+++ b/wpimath/src/test/native/cpp/optimization/NonlinearProblemTest.cpp
@@ -2,9 +2,9 @@
 // Open Source Software; you can modify and/or share it under the terms of
 // the WPILib BSD license file in the root directory of this project.
 
-#include <concepts>
 #include <ranges>
 
+#include <fmt/base.h>
 #include <gtest/gtest.h>
 #include <sleipnir/autodiff/expression_type.hpp>
 #include <sleipnir/optimization/problem.hpp>
@@ -17,6 +17,8 @@ auto Range(T start, T end, T step) {
 }
 
 TEST(ProblemTest, Quartic) {
+  testing::internal::CaptureStdout();
+
   slp::Problem problem;
 
   auto x = problem.decision_variable();
@@ -33,9 +35,15 @@ TEST(ProblemTest, Quartic) {
   EXPECT_EQ(problem.solve({.diagnostics = true}), slp::ExitStatus::SUCCESS);
 
   EXPECT_NEAR(x.value(), 1.0, 1e-6);
+
+  if (auto output = testing::internal::GetCapturedStdout(); HasFailure()) {
+    fmt::println("{}", output);
+  }
 }
 
 TEST(ProblemTest, RosenbrockWithCubicAndLineConstraint) {
+  testing::internal::CaptureStdout();
+
   // https://en.wikipedia.org/wiki/Test_functions_for_optimization#Test_functions_for_constrained_optimization
   for (auto x0 : Range(-1.5, 1.5, 0.1)) {
     for (auto y0 : Range(-0.5, 2.5, 0.1)) {
@@ -68,9 +76,15 @@ TEST(ProblemTest, RosenbrockWithCubicAndLineConstraint) {
       EXPECT_TRUE((near(0.0, y.value(), 1e-2) || near(1.0, y.value(), 1e-2)));
     }
   }
+
+  if (auto output = testing::internal::GetCapturedStdout(); HasFailure()) {
+    fmt::println("{}", output);
+  }
 }
 
 TEST(ProblemTest, RosenbrockWithDiskConstraint) {
+  testing::internal::CaptureStdout();
+
   // https://en.wikipedia.org/wiki/Test_functions_for_optimization#Test_functions_for_constrained_optimization
   for (auto x0 : Range(-1.5, 1.5, 0.1)) {
     for (auto y0 : Range(-1.5, 1.5, 0.1)) {
@@ -96,9 +110,15 @@ TEST(ProblemTest, RosenbrockWithDiskConstraint) {
       EXPECT_NEAR(y.value(), 1.0, 1e-3);
     }
   }
+
+  if (auto output = testing::internal::GetCapturedStdout(); HasFailure()) {
+    fmt::println("{}", output);
+  }
 }
 
 TEST(ProblemTest, Minimum2DDistanceWithLinearConstraint) {
+  testing::internal::CaptureStdout();
+
   slp::Problem problem;
 
   auto x = problem.decision_variable();
@@ -126,9 +146,15 @@ TEST(ProblemTest, Minimum2DDistanceWithLinearConstraint) {
 
   EXPECT_NEAR(x.value(), 2.5, 1e-2);
   EXPECT_NEAR(y.value(), 2.5, 1e-2);
+
+  if (auto output = testing::internal::GetCapturedStdout(); HasFailure()) {
+    fmt::println("{}", output);
+  }
 }
 
 TEST(ProblemTest, ConflictingBounds) {
+  testing::internal::CaptureStdout();
+
   slp::Problem problem;
 
   auto x = problem.decision_variable();
@@ -147,9 +173,15 @@ TEST(ProblemTest, ConflictingBounds) {
 
   EXPECT_EQ(problem.solve({.diagnostics = true}),
             slp::ExitStatus::GLOBALLY_INFEASIBLE);
+
+  if (auto output = testing::internal::GetCapturedStdout(); HasFailure()) {
+    fmt::println("{}", output);
+  }
 }
 
 TEST(ProblemTest, WachterAndBieglerLineSearchFailure) {
+  testing::internal::CaptureStdout();
+
   // See example 19.2 of [1]
   //
   // [1] Nocedal, J. and Wright, S. "Numerical Optimization", 2nd. ed., Ch. 19.
@@ -183,4 +215,8 @@ TEST(ProblemTest, WachterAndBieglerLineSearchFailure) {
   // EXPECT_EQ(x.value(), 1.0);
   // EXPECT_EQ(s1.value(), 0.0);
   // EXPECT_EQ(s2.value(), 0.5);
+
+  if (auto output = testing::internal::GetCapturedStdout(); HasFailure()) {
+    fmt::println("{}", output);
+  }
 }