SyncValsverifier → artifact → classifier → verdict
SyncVals · Trajectory

pipeflow-colebrook-solver

claude-code claude-opus-4-8 ✗ failed GOOD_FAILURE ↑ View task
Solved from the instruction alone, tests/ and solution/ were withheld from the agent's workspace and restored only for grading.
Reward = tests/test.sh exit code (0 → resolved); the classification below is post-hoc and cannot change it.
Classification , post-hoc; cannot change the reward
GOOD_FAILUREHonest miss, the agent ran correctly but couldn't solve it. Expected for a hard task; the task is sound.
SubtypeIncomplete Implementation - Solver works on simple cases but fails on complex networks
EvidenceAgent trajectory shows the solver passes the smoke test (1/1) but the verifier's hidden tests (which replace the smoke tests) show 33% pass rate with failures: 'edge energy residual within tolerance' (5 failures), 'check-valve complementarity within tolerance' (1 failure), and 'no reverse flow through the check valve' (1 failure). The agent implemented a damped Newton solver that converges correctly on the two-loop example but fails on more complex networks including those with cycles, multiple reservoirs, and valve interactions. Test output shows 9/27 tests passing across analytic, minor, valve, and soak test suites."
Root causeThe agent implemented a reasonable but incomplete damped Newton solver that handles simple networks and the smoke test correctly, but fails to accurately solve complex networks with multiple loops, cycles, and check valve complementarity constraints that are verified by the hidden test suite.
RecommendationN/A - task is fine. The instruction is clear (implement steady-state solver), baseline validation confirmed oracle passes and nop fails, hidden tests validate legitimate physics constraints (continuity, energy balance, valve complementarity). The agent's implementation is simply insufficient for the harder cases; this is normal for a complex numerical problem.
Trajectory
Tool-by-tool agent trajectory
24 tool calls · 4 tool types · 38 steps
# Ticket: Implement the steady-state hydraulic pipe-network solver ## Context `pipeflow` is a C++17 hydraulics engine. The surrounding framework is complete; `src/solver.cpp` contains the failing stub for `NetworkSolver::solve()`. The project is at `/opt/pipeflow` in the build image. ## Your Task Implement `NetworkSolver::solve()` in `/opt/pipeflow/src/solver.cpp` so the project builds and the test suite passes. Only edit `src/solver.cpp`; do not change the public headers or signatures. Refer to the headers under `include/` and the shipped kernel primitives for the API you must implement. ## Build and Test ``` cmake -S /opt/pipeflow -B /opt/pipeflow/build -DCMAKE_BUILD_TYPE=Release cmake --build /opt/pipeflow/build --parallel cd /opt/pipeflow/build && ctest --output-on-failure ```
I'll start by exploring the project structure to understand the codebase.

List project structure

shell
ls -R --ignore=build --ignore=.git 2>/dev/null | head -100
output
.:
CMakeLists.txt
examples
include
src
tests

./examples:
two_loop_network.net

./include:
pipeflow

./include/pipeflow:
io.hpp
solver.hpp
types.hpp

./src:
io.cpp
kernel.cpp
main.cpp
solver.cpp
types.cpp

./tests:
CMakeLists.txt
test_smoke.cpp
test_util.hpp

[stdout]
.:
CMakeLists.txt
examples
include
src
tests

./examples:
two_loop_network.net

./include:
pipeflow

./include/pipeflow:
io.hpp
solver.hpp
types.hpp

./src:
io.cpp
kernel.cpp
main.cpp
solver.cpp
types.cpp

./tests:
CMakeLists.txt
test_smoke.cpp
test_util.hpp

/opt/pipeflow/src/solver.cpp

contents
1	#include "pipeflow/solver.hpp"
2	
3	#include <cstddef>
4	#include <vector>
5	
6	#include "pipeflow/types.hpp"
7	
8	namespace pipeflow {
9	
10	// TODO(candidate): solve the coupled continuity + energy system.
11	// The energy law uses piezometric head, static elevation lift, and the sum of
12	// shipped friction plus directional minor-loss primitives. Do not change public
13	// signatures or reimplement the kernel primitives. The solving method is yours;
14	// only the returned physical state is checked.
15	
16	NetworkSolver::NetworkSolver(const Network& network,
17	                             const SolverOptions& options)
18	    : network_(network), options_(options) {}
19	
20	Solution NetworkSolver::solve() const {
21	    network_.validate();
22	
23	    Solution sol;
24	    sol.pipe_flow.assign(network_.pipe_count(), 0.0);
25	    sol.node_head.assign(network_.node_count(), 0.0);
26	    for (const auto& nd : network_.nodes) {
27	        if (nd.is_reservoir) sol.node_head[nd.id] = nd.head;
28	    }
29	
30	    // TODO(candidate): solve the coupled continuity + energy system here.
31	    sol.report.iterations = 0;
32	    sol.report.residual = 0.0;
33	    sol.report.converged = false;
34	    return sol;
35	}
36	
37	} // namespace pipeflow
38
Let me read the headers and kernel to understand the API.

/opt/pipeflow/include/pipeflow/types.hpp

contents
1	#ifndef PIPEFLOW_TYPES_HPP
2	#define PIPEFLOW_TYPES_HPP
3	
4	#include <cstddef>
5	#include <string>
6	#include <vector>
7	
8	namespace pipeflow {
9	
10	
11	
12	
13	
14	
15	
16	
17	
18	struct Fluid {
19	    double density{998.0};      
20	    double viscosity{1.002e-3}; 
21	    double gravity{9.80665};    
22	
23	    
24	    void validate() const;
25	};
26	
27	
28	
29	
30	
31	
32	
33	
34	
35	
36	
37	
38	
39	
40	
41	
42	
43	
44	
45	
46	
47	class Pipe {
48	public:
49	    Pipe(std::size_t from, std::size_t to, double diameter, double length,
50	         double roughness, double minor_K = 0.0, bool check_valve = false,
51	         double minor_K_rev = -1.0);
52	
53	    std::size_t from() const { return from_; }
54	    std::size_t to() const { return to_; }
55	    double diameter() const { return diameter_; }
56	    double length() const { return length_; }
57	    double roughness() const { return roughness_; }
58	    double minor_K() const { return minor_K_; }
59	    double minor_K_rev() const { return minor_K_rev_; }
60	    bool check_valve() const { return check_valve_; }
61	
62	    
63	    double area() const;
64	
65	    
66	    double relative_roughness() const { return roughness_ / diameter_; }
67	
68	    
69	    double velocity(double Q) const;
70	
71	    
72	    
73	    double reynolds(double Q, const Fluid& fluid) const;
74	
75	    
76	    
77	    void validate() const;
78	
79	private:
80	    std::size_t from_;
81	    std::size_t to_;
82	    double diameter_;
83	    double length_;
84	    double roughness_;
85	    double minor_K_;
86	    double minor_K_rev_;
87	    bool check_valve_;
88	};
89	
90	
91	
92	
93	
94	
95	
96	
97	
98	
99	
100	
101	struct Node {
102	    std::size_t id{0};        
103	    bool is_reservoir{false}; 
104	    double head{0.0};         
105	    double demand{0.0};       
106	    double elevation{0.0};    
107	    double emitter_coeff{0.0}; 
108	    bool is_emitter{false};   
109	};
110	
111	
112	
113	
114	
115	struct Network {
116	    Fluid fluid{};
117	    std::vector<Node> nodes{};
118	    std::vector<Pipe> pipes{};
119	
120	    std::size_t node_count() const { return nodes.size(); }
121	    std::size_t pipe_count() const { return pipes.size(); }
122	
123	    
124	    std::size_t reservoir_count() const;
125	
126	    
127	    
128	    
129	    
130	    
131	    
132	    
133	    
134	    
135	    
136	    
137	    void validate() const;
138	
139	    
140	    std::vector<std::size_t> incident_pipes(std::size_t n) const;
141	};
142	
143	} 
144	
145	#endif 
146

/opt/pipeflow/include/pipeflow/solver.hpp

contents
1	#ifndef PIPEFLOW_SOLVER_HPP
2	#define PIPEFLOW_SOLVER_HPP
3	
4	#include <cstddef>
5	#include <vector>
6	
7	#include "pipeflow/types.hpp"
8	
9	namespace pipeflow {
10	
11	
12	
13	
14	
15	
16	constexpr double kLaminarReynolds = 2300.0;
17	
18	
19	
20	
21	
22	
23	
24	
25	
26	
27	
28	
29	double friction_factor(double Re, double rel_roughness);
30	
31	
32	
33	
34	double pipe_head_loss(const Pipe& pipe, double Q, const Fluid& fluid);
35	
36	
37	
38	
39	
40	double pipe_head_loss_deriv(const Pipe& pipe, double Q, const Fluid& fluid);
41	
42	
43	
44	
45	
46	double minor_loss(const Pipe& pipe, double Q, const Fluid& fluid);
47	
48	
49	double minor_loss_deriv(const Pipe& pipe, double Q, const Fluid& fluid);
50	
51	
52	struct SolverOptions {
53	    int max_iterations{200};     
54	    double tolerance{1e-10};     
55	    double min_damping{1e-4};    
56	};
57	
58	
59	struct SolveReport {
60	    int iterations{0};       
61	    double residual{0.0};    
62	    bool converged{false};   
63	};
64	
65	
66	
67	
68	struct Solution {
69	    std::vector<double> pipe_flow;  
70	    std::vector<double> node_head;  
71	    SolveReport report;
72	};
73	
74	
75	
76	
77	
78	
79	
80	
81	
82	
83	
84	class NetworkSolver {
85	public:
86	    explicit NetworkSolver(const Network& network,
87	                           const SolverOptions& options = SolverOptions{});
88	
89	    
90	    
91	    
92	    
93	    Solution solve() const;
94	
95	    const Network& network() const { return network_; }
96	    const SolverOptions& options() const { return options_; }
97	
98	private:
99	    const Network& network_;
100	    SolverOptions options_;
101	};
102	
103	} 
104	
105	#endif 
106

/opt/pipeflow/include/pipeflow/io.hpp

contents
1	#ifndef PIPEFLOW_IO_HPP
2	#define PIPEFLOW_IO_HPP
3	
4	#include <iosfwd>
5	#include <string>
6	
7	#include "pipeflow/types.hpp"
8	
9	namespace pipeflow {
10	
11	
12	
13	
14	
15	
16	
17	
18	
19	
20	
21	
22	
23	
24	
25	
26	
27	
28	
29	
30	Network parse_network(std::istream& in);
31	
32	
33	Network parse_network_file(const std::string& path);
34	
35	
36	
37	
38	void write_report(std::ostream& out, const Network& network);
39	
40	} 
41	
42	#endif 
43
Now let me read the kernel primitives and the types implementation to understand the physics conventions.

/opt/pipeflow/src/kernel.cpp

contents
1	#include <algorithm>
2	#include <cmath>
3	#include <stdexcept>
4	
5	#include "pipeflow/solver.hpp"
6	#include "pipeflow/types.hpp"
7	
8	// Framework "kernel" primitives shared by the network solver and the tests:
9	//   * the Darcy friction factor (exact laminar law + Newton solve of the
10	//     implicit Colebrook-White equation), and
11	//   * the signed Darcy-Weisbach per-pipe head loss h_f(Q) and its derivative.
12	// These are fully implemented support code; the candidate implements only the
13	// NetworkSolver in src/solver.cpp.
14	
15	namespace pipeflow {
16	
17	double friction_factor(double Re, double rel_roughness) {
18	    if (!(Re > 0.0)) {
19	        throw std::runtime_error(
20	            "friction_factor: Reynolds number must be positive");
21	    }
22	    if (rel_roughness < 0.0) {
23	        throw std::runtime_error(
24	            "friction_factor: relative roughness must be non-negative");
25	    }
26	
27	    // Laminar regime: exact, explicit.
28	    if (Re <= kLaminarReynolds) {
29	        return 64.0 / Re;
30	    }
31	
32	    // Turbulent regime: solve  1/sqrt(f) = -2 log10(rr/3.7 + 2.51/(Re sqrt(f))).
33	    // Let x = 1/sqrt(f); find the root of
34	    //   g(x) = x + 2 log10(rr/3.7 + 2.51 x / Re).
35	    const double rr = rel_roughness;
36	    const double ln10 = std::log(10.0);
37	
38	    // Initial guess from the explicit Swamee-Jain correlation.
39	    const double sj_denom = std::log10(rr / 3.7 + 5.74 / std::pow(Re, 0.9));
40	    double f0 = 0.25 / (sj_denom * sj_denom);
41	    if (!(f0 > 0.0) || !std::isfinite(f0)) f0 = 0.02;
42	    double x = 1.0 / std::sqrt(f0);
43	
44	    const int max_iter = 100;
45	    bool converged = false;
46	    for (int it = 0; it < max_iter; ++it) {
47	        const double arg = rr / 3.7 + 2.51 * x / Re;
48	        const double g = x + 2.0 * std::log10(arg);
49	        const double dg = 1.0 + (2.0 / ln10) * (2.51 / Re) / arg;
50	        const double dx = g / dg;
51	        x -= dx;
52	        if (std::fabs(g) < 1e-12 || std::fabs(dx) < 1e-14) {
53	            converged = true;
54	            break;
55	        }
56	    }
57	    if (!converged) {
58	        throw std::runtime_error(
59	            "friction_factor: Colebrook Newton iteration failed to converge");
60	    }
61	    return 1.0 / (x * x);
62	}
63	
64	double pipe_head_loss(const Pipe& pipe, double Q, const Fluid& fluid) {
65	    if (Q == 0.0) return 0.0;
66	    const double absQ = std::fabs(Q);
67	    const double V = absQ / pipe.area();
68	    const double Re = pipe.reynolds(Q, fluid);
69	    const double f = friction_factor(Re, pipe.relative_roughness());
70	    const double mag = f * (pipe.length() / pipe.diameter()) * (V * V) /
71	                       (2.0 * fluid.gravity);
72	    return (Q > 0.0) ? mag : -mag;
73	}
74	
75	double pipe_head_loss_deriv(const Pipe& pipe, double Q, const Fluid& fluid) {
76	    // h_f(Q) is an odd, monotone function, so d h_f/dQ is even and positive.
77	    // In the laminar regime f = 64/Re = 64 mu / (rho |V| D) with V = |Q|/A, so
78	    //   |h_f| = 64 mu L / (rho D^2 A 2 g) * |Q|   (LINEAR in |Q|)  =>  slope c.
79	    // In the turbulent regime f varies slowly, so a tight central difference on
80	    // the magnitude gives an accurate, robust derivative everywhere.
81	    const double A = pipe.area();
82	    const double Re = pipe.reynolds(Q, fluid);
83	    if (Re <= kLaminarReynolds) {
84	        // Exact laminar slope d|h_f|/d|Q|.
85	        return 64.0 * fluid.viscosity * pipe.length() /
86	               (fluid.density * pipe.diameter() * pipe.diameter() * A * 2.0 *
87	                fluid.gravity);
88	    }
89	    const double absQ = std::fabs(Q);
90	    // Relative step, floored so we never differentiate at exactly zero flow.
91	    const double h = std::max(1e-9, 1e-7 * absQ);
92	    const double qp = absQ + h;
93	    const double qm = std::max(absQ - h, 0.5 * h);
94	    const double hp = pipe_head_loss(pipe, qp, fluid);
95	    const double hm = pipe_head_loss(pipe, qm, fluid);
96	    return (hp - hm) / (qp - qm);
97	}
98	
99	double minor_loss(const Pipe& pipe, double Q, const Fluid& fluid) {
100	    const double K = Q >= 0.0 ? pipe.minor_K() : pipe.minor_K_rev();
101	    if (Q == 0.0 || K == 0.0) return 0.0;
102	    const double V = std::fabs(Q) / pipe.area();
103	    const double mag = K * (V * V) / (2.0 * fluid.gravity);
104	    return (Q > 0.0) ? mag : -mag;
105	}
106	
107	double minor_loss_deriv(const Pipe& pipe, double Q, const Fluid& fluid) {
108	    const double K = Q >= 0.0 ? pipe.minor_K() : pipe.minor_K_rev();
109	    if (K == 0.0 || Q == 0.0) return 0.0;
110	    const double A = pipe.area();
111	    return K * std::fabs(Q) / (A * A * fluid.gravity);
112	}
113	
114	} // namespace pipeflow
115

/opt/pipeflow/src/types.cpp

contents
1	#include "pipeflow/types.hpp"
2	
3	#include <cmath>
4	#include <queue>
5	#include <stdexcept>
6	#include <string>
7	#include <vector>
8	
9	namespace pipeflow {
10	
11	void Fluid::validate() const {
12	    if (!(density > 0.0)) {
13	        throw std::invalid_argument("Fluid: density must be positive");
14	    }
15	    if (!(viscosity > 0.0)) {
16	        throw std::invalid_argument("Fluid: viscosity must be positive");
17	    }
18	    if (!(gravity > 0.0)) {
19	        throw std::invalid_argument("Fluid: gravity must be positive");
20	    }
21	}
22	
23	Pipe::Pipe(std::size_t from, std::size_t to, double diameter, double length,
24	           double roughness, double minor_K, bool check_valve,
25	           double minor_K_rev)
26	    : from_(from),
27	      to_(to),
28	      diameter_(diameter),
29	      length_(length),
30	      roughness_(roughness),
31	      minor_K_(minor_K),
32	      minor_K_rev_(minor_K_rev < 0.0 ? minor_K : minor_K_rev),
33	      check_valve_(check_valve) {
34	    validate();
35	}
36	
37	double Pipe::area() const {
38	    constexpr double pi = 3.14159265358979323846;
39	    return 0.25 * pi * diameter_ * diameter_;
40	}
41	
42	double Pipe::velocity(double Q) const { return std::fabs(Q) / area(); }
43	
44	double Pipe::reynolds(double Q, const Fluid& fluid) const {
45	    return fluid.density * velocity(Q) * diameter_ / fluid.viscosity;
46	}
47	
48	void Pipe::validate() const {
49	    if (from_ == to_) {
50	        throw std::invalid_argument("Pipe: endpoints must be distinct");
51	    }
52	    if (!(diameter_ > 0.0)) {
53	        throw std::invalid_argument("Pipe: diameter must be positive");
54	    }
55	    if (!(length_ > 0.0)) {
56	        throw std::invalid_argument("Pipe: length must be positive");
57	    }
58	    if (roughness_ < 0.0) {
59	        throw std::invalid_argument("Pipe: roughness must be non-negative");
60	    }
61	    if (minor_K_ < 0.0) {
62	        throw std::invalid_argument(
63	            "Pipe: minor-loss coefficient must be non-negative");
64	    }
65	    if (minor_K_rev_ < 0.0) {
66	        throw std::invalid_argument(
67	            "Pipe: reverse minor-loss coefficient must be non-negative");
68	    }
69	}
70	
71	std::size_t Network::reservoir_count() const {
72	    std::size_t n = 0;
73	    for (const auto& nd : nodes) {
74	        if (nd.is_reservoir) ++n;
75	    }
76	    return n;
77	}
78	
79	std::vector<std::size_t> Network::incident_pipes(std::size_t n) const {
80	    std::vector<std::size_t> out;
81	    for (std::size_t p = 0; p < pipes.size(); ++p) {
82	        if (pipes[p].from() == n || pipes[p].to() == n) out.push_back(p);
83	    }
84	    return out;
85	}
86	
87	void Network::validate() const {
88	    fluid.validate();
89	
90	    const std::size_t n = nodes.size();
91	    if (n == 0) {
92	        throw std::invalid_argument("Network: no nodes");
93	    }
94	    if (pipes.empty()) {
95	        throw std::invalid_argument("Network: no pipes");
96	    }
97	
98	    for (std::size_t i = 0; i < n; ++i) {
99	        if (nodes[i].id != i) {
100	            throw std::invalid_argument(
101	                "Network: node " + std::to_string(i) +
102	                " has inconsistent id " + std::to_string(nodes[i].id));
103	        }
104	        if (nodes[i].emitter_coeff < 0.0) {
105	            throw std::invalid_argument(
106	                "Network: node " + std::to_string(i) +
107	                " has negative emitter coefficient");
108	        }
109	    }
110	
111	    for (std::size_t p = 0; p < pipes.size(); ++p) {
112	        pipes[p].validate();
113	        if (pipes[p].from() >= n || pipes[p].to() >= n) {
114	            throw std::invalid_argument(
115	                "Network: pipe " + std::to_string(p) +
116	                " references an out-of-range node index");
117	        }
118	    }
119	
120	    if (reservoir_count() == 0) {
121	        throw std::invalid_argument(
122	            "Network: at least one fixed-head reservoir node is required "
123	            "(the head datum is otherwise undefined / under-determined)");
124	    }
125	
126	    // Every node must touch at least one pipe.
127	    std::vector<int> degree(n, 0);
128	    for (const auto& pp : pipes) {
129	        ++degree[pp.from()];
130	        ++degree[pp.to()];
131	    }
132	    for (std::size_t i = 0; i < n; ++i) {
133	        if (degree[i] == 0) {
134	            throw std::invalid_argument(
135	                "Network: node " + std::to_string(i) +
136	                " is disconnected (incident on no pipe)");
137	        }
138	    }
139	
140	    // Every junction must reach a reservoir through the pipe graph. Multi-source
141	    // BFS from all reservoirs; any unreached node has no head reference.
142	    std::vector<std::vector<std::size_t>> adj(n);
143	    for (const auto& pp : pipes) {
144	        adj[pp.from()].push_back(pp.to());
145	        adj[pp.to()].push_back(pp.from());
146	    }
147	    std::vector<char> seen(n, 0);
148	    std::queue<std::size_t> bfs;
149	    for (std::size_t i = 0; i < n; ++i) {
150	        if (nodes[i].is_reservoir) {
151	            seen[i] = 1;
152	            bfs.push(i);
153	        }
154	    }
155	    while (!bfs.empty()) {
156	        const std::size_t u = bfs.front();
157	        bfs.pop();
158	        for (std::size_t v : adj[u]) {
159	            if (!seen[v]) {
160	                seen[v] = 1;
161	                bfs.push(v);
162	            }
163	        }
164	    }
165	    for (std::size_t i = 0; i < n; ++i) {
166	        if (!seen[i]) {
167	            throw std::invalid_argument(
168	                "Network: node " + std::to_string(i) +
169	                " has no path to any fixed-head reservoir");
170	        }
171	    }
172	}
173	
174	} // namespace pipeflow
175
Now let me look at the tests and IO to understand expectations and conventions.

/opt/pipeflow/tests/test_smoke.cpp

contents
1	#include <stdexcept>
2	
3	#include "pipeflow/solver.hpp"
4	#include "pipeflow/types.hpp"
5	#include "test_util.hpp"
6	
7	using namespace pipeflow;
8	
9	PIPEFLOW_TEST("single_pipe_smoke") {
10	    Network net;
11	    net.fluid = Fluid{998.0, 1.002e-3, 9.80665};
12	    net.nodes = {Node{0, true, 20.0, 0.0}, Node{1, true, 10.0, 0.0}};
13	    net.pipes = {Pipe(0, 1, 0.15, 250.0, 4.5e-5)};
14	
15	    const Solution sol = NetworkSolver(net).solve();
16	    pipeflow_test::expect(sol.report.converged, "solver reports convergence");
17	    pipeflow_test::expect(sol.pipe_flow.size() == 1, "one pipe flow returned");
18	    pipeflow_test::expect(sol.pipe_flow[0] > 0.0,
19	                          "flow runs from high head to low head");
20	}
21	
22	PIPEFLOW_TEST("no_reservoir_throws") {
23	    Network net;
24	    net.fluid = Fluid{998.0, 1.002e-3, 9.80665};
25	    net.nodes = {Node{0, false, 0.0, 0.01}, Node{1, false, 0.0, 0.0}};
26	    net.pipes = {Pipe(0, 1, 0.1, 100.0, 1e-5)};
27	
28	    bool threw = false;
29	    try {
30	        (void)NetworkSolver(net).solve();
31	    } catch (const std::invalid_argument&) {
32	        threw = true;
33	    }
34	    pipeflow_test::expect(threw, "network without reservoir throws");
35	}
36	
37	PIPEFLOW_TEST_MAIN()
38

/opt/pipeflow/tests/test_util.hpp

contents
1	#ifndef PIPEFLOW_TEST_UTIL_HPP
2	#define PIPEFLOW_TEST_UTIL_HPP
3	
4	// Minimal dependency-free test harness for the pipeflow suite.
5	//
6	// Each test executable defines test functions and registers them with
7	// PIPEFLOW_TEST(name) { ... }. main() (provided by PIPEFLOW_TEST_MAIN) runs
8	// every registered test and returns non-zero if any assertion fails, which
9	// CTest interprets as a failure.
10	
11	#include <cmath>
12	#include <cstddef>
13	#include <functional>
14	#include <iostream>
15	#include <string>
16	#include <vector>
17	
18	namespace pipeflow_test {
19	
20	struct Case {
21	    std::string name;
22	    std::function<void()> fn;
23	};
24	
25	inline std::vector<Case>& registry() {
26	    static std::vector<Case> cases;
27	    return cases;
28	}
29	
30	struct Registrar {
31	    Registrar(const std::string& name, std::function<void()> fn) {
32	        registry().push_back(Case{name, std::move(fn)});
33	    }
34	};
35	
36	// Thrown by an assertion failure to abort the current test case.
37	struct AssertionError {
38	    std::string message;
39	};
40	
41	inline void expect(bool cond, const std::string& what) {
42	    if (!cond) {
43	        throw AssertionError{what};
44	    }
45	}
46	
47	inline void expect_near(double got, double want, double tol, const std::string& what) {
48	    if (std::fabs(got - want) > tol) {
49	        throw AssertionError{what + " (got " + std::to_string(got) +
50	                             ", want " + std::to_string(want) +
51	                             ", tol " + std::to_string(tol) + ")"};
52	    }
53	}
54	
55	// Relative-error check (with an absolute floor) for quantities whose scale
56	// varies widely across cases.
57	inline void expect_rel(double got, double want, double rel_tol,
58	                       const std::string& what) {
59	    const double denom = std::fabs(want) > 1e-300 ? std::fabs(want) : 1.0;
60	    if (std::fabs(got - want) / denom > rel_tol) {
61	        throw AssertionError{what + " (got " + std::to_string(got) +
62	                             ", want " + std::to_string(want) +
63	                             ", rel_tol " + std::to_string(rel_tol) + ")"};
64	    }
65	}
66	
67	inline int run_all() {
68	    int failures = 0;
69	    for (const auto& c : registry()) {
70	        try {
71	            c.fn();
72	            std::cout << "[ PASS ] " << c.name << "\n";
73	        } catch (const AssertionError& e) {
74	            std::cout << "[ FAIL ] " << c.name << ": " << e.message << "\n";
75	            ++failures;
76	        } catch (const std::exception& e) {
77	            std::cout << "[ FAIL ] " << c.name
78	                      << ": unexpected exception: " << e.what() << "\n";
79	            ++failures;
80	        } catch (...) {
81	            std::cout << "[ FAIL ] " << c.name << ": unknown exception\n";
82	            ++failures;
83	        }
84	    }
85	    std::cout << "----\n"
86	              << (registry().size() - failures) << "/" << registry().size()
87	              << " tests passed\n";
88	    return failures == 0 ? 0 : 1;
89	}
90	
91	} // namespace pipeflow_test
92	
93	#define PIPEFLOW_CONCAT_INNER(a, b) a##b
94	#define PIPEFLOW_CONCAT(a, b) PIPEFLOW_CONCAT_INNER(a, b)
95	
96	#define PIPEFLOW_TEST(NAME)                                                    \
97	    static void PIPEFLOW_CONCAT(pipeflow_test_fn_, __LINE__)();                \
98	    static ::pipeflow_test::Registrar PIPEFLOW_CONCAT(pipeflow_test_reg_,     \
99	                                                      __LINE__){               \
100	        NAME, &PIPEFLOW_CONCAT(pipeflow_test_fn_, __LINE__)};                  \
101	    static void PIPEFLOW_CONCAT(pipeflow_test_fn_, __LINE__)()
102	
103	#define PIPEFLOW_TEST_MAIN()                                                   \
104	    int main() { return ::pipeflow_test::run_all(); }
105	
106	#endif // PIPEFLOW_TEST_UTIL_HPP
107

/opt/pipeflow/src/io.cpp

contents
1	#include "pipeflow/io.hpp"
2	
3	#include <cstddef>
4	#include <fstream>
5	#include <iomanip>
6	#include <map>
7	#include <sstream>
8	#include <stdexcept>
9	#include <string>
10	#include <vector>
11	
12	#include "pipeflow/solver.hpp"
13	
14	namespace pipeflow {
15	
16	namespace {
17	
18	[[noreturn]] void fail(std::size_t line_no, const std::string& msg) {
19	    std::ostringstream oss;
20	    oss << "parse_network: line " << line_no << ": " << msg;
21	    throw std::runtime_error(oss.str());
22	}
23	
24	} // namespace
25	
26	Network parse_network(std::istream& in) {
27	    Fluid fluid{};
28	    bool have_fluid = false;
29	
30	    // Collect nodes by id (sparse) then compact into a contiguous vector.
31	    std::map<std::size_t, Node> node_by_id;
32	    struct RawPipe {
33	        std::size_t from, to;
34	        double D, L, eps;
35	        double minor_K{0.0};
36	        double minor_K_rev{-1.0};
37	        bool check_valve{false};
38	        std::size_t line;
39	    };
40	    std::vector<RawPipe> raw_pipes;
41	
42	    std::string line;
43	    std::size_t line_no = 0;
44	    while (std::getline(in, line)) {
45	        ++line_no;
46	        const auto hash = line.find('#');
47	        if (hash != std::string::npos) line.erase(hash);
48	        std::istringstream ls(line);
49	        std::string tag;
50	        if (!(ls >> tag)) continue;
51	
52	        if (tag == "fluid") {
53	            if (have_fluid) fail(line_no, "duplicate 'fluid' record");
54	            if (!(ls >> fluid.density >> fluid.viscosity >> fluid.gravity)) {
55	                fail(line_no, "fluid needs: <density> <viscosity> <gravity>");
56	            }
57	            have_fluid = true;
58	        } else if (tag == "node") {
59	            std::size_t id;
60	            std::string kind;
61	            double value;
62	            if (!(ls >> id >> kind >> value)) {
63	                fail(line_no, "node needs: <id> reservoir|demand <value>");
64	            }
65	            if (node_by_id.count(id)) {
66	                fail(line_no, "node id " + std::to_string(id) +
67	                                  " declared more than once");
68	            }
69	            Node nd;
70	            nd.id = id;
71	            if (kind == "reservoir") {
72	                nd.is_reservoir = true;
73	                nd.head = value;
74	            } else if (kind == "demand") {
75	                nd.is_reservoir = false;
76	                nd.demand = value;
77	            } else {
78	                fail(line_no, "node kind must be 'reservoir' or 'demand', got '" +
79	                                  kind + "'");
80	            }
81	            std::string opt;
82	            while (ls >> opt) {
83	                if (opt == "elev") {
84	                    if (!(ls >> nd.elevation)) {
85	                        fail(line_no, "'elev' needs a numeric elevation");
86	                    }
87	                } else {
88	                    fail(line_no, "unknown node option '" + opt + "'");
89	                }
90	            }
91	            node_by_id.emplace(id, nd);
92	        } else if (tag == "pipe") {
93	            RawPipe rp{};
94	            rp.line = line_no;
95	            if (!(ls >> rp.from >> rp.to >> rp.D >> rp.L >> rp.eps)) {
96	                fail(line_no,
97	                     "pipe needs: <from> <to> <diameter> <length> <roughness>");
98	            }
99	            std::string opt;
100	            while (ls >> opt) {
101	                if (opt == "minor") {
102	                    if (!(ls >> rp.minor_K)) {
103	                        fail(line_no, "'minor' needs a numeric coefficient");
104	                    }
105	                } else if (opt == "minor_rev") {
106	                    if (!(ls >> rp.minor_K_rev)) {
107	                        fail(line_no, "'minor_rev' needs a numeric coefficient");
108	                    }
109	                } else if (opt == "check") {
110	                    rp.check_valve = true;
111	                } else {
112	                    fail(line_no, "unknown pipe option '" + opt + "'");
113	                }
114	            }
115	            raw_pipes.push_back(rp);
116	        } else {
117	            fail(line_no, "unknown record '" + tag + "'");
118	        }
119	    }
120	
121	    if (node_by_id.empty()) fail(line_no, "no nodes declared");
122	
123	    // Node ids must be contiguous 0..n-1.
124	    const std::size_t n = node_by_id.size();
125	    Network net;
126	    net.fluid = fluid;
127	    net.nodes.reserve(n);
128	    for (std::size_t i = 0; i < n; ++i) {
129	        auto it = node_by_id.find(i);
130	        if (it == node_by_id.end()) {
131	            fail(line_no, "node ids must be contiguous 0.." +
132	                              std::to_string(n - 1) + " (missing id " +
133	                              std::to_string(i) + ")");
134	        }
135	        net.nodes.push_back(it->second);
136	    }
137	
138	    net.pipes.reserve(raw_pipes.size());
139	    for (const auto& rp : raw_pipes) {
140	        // Pipe's own ctor validates geometry; surface a line number on failure.
141	        try {
142	            net.pipes.emplace_back(rp.from, rp.to, rp.D, rp.L, rp.eps,
143	                                   rp.minor_K, rp.check_valve, rp.minor_K_rev);
144	        } catch (const std::exception& ex) {
145	            fail(rp.line, std::string("bad pipe geometry: ") + ex.what());
146	        }
147	    }
148	
149	    net.validate();
150	    return net;
151	}
152	
153	Network parse_network_file(const std::string& path) {
154	    std::ifstream in(path);
155	    if (!in) {
156	        throw std::runtime_error("parse_network_file: cannot open '" + path +
157	                                 "'");
158	    }
159	    return parse_network(in);
160	}
161	
162	void write_report(std::ostream& out, const Network& network) {
163	    NetworkSolver solver(network);
164	    const Solution sol = solver.solve();
165	
166	    out << std::scientific << std::setprecision(6);
167	    out << "# pipe-network (continuity + Darcy/Colebrook + directional fittings) report\n";
168	    out << "converged=" << (sol.report.converged ? "yes" : "no")
169	        << " iterations=" << sol.report.iterations
170	        << " residual=" << sol.report.residual << " m^3/s\n";
171	    out << "# nodes: id  type        head[m]      demand[m^3/s]  elev[m]\n";
172	    for (const auto& nd : network.nodes) {
173	        out << "node " << nd.id << "  "
174	            << (nd.is_reservoir ? "reservoir " : "junction  ") << "  "
175	            << sol.node_head[nd.id] << "  "
176	            << (nd.is_reservoir ? 0.0 : nd.demand) << "  "
177	            << nd.elevation << "\n";
178	    }
179	    out << "# pipes: from->to   Q[m^3/s]     V[m/s]       head_loss[m]\n";
180	    for (std::size_t p = 0; p < network.pipes.size(); ++p) {
181	        const Pipe& pp = network.pipes[p];
182	        const double Q = sol.pipe_flow[p];
183	        out << "pipe " << pp.from() << "->" << pp.to() << "  " << Q << "  "
184	            << pp.velocity(Q) << "  "
185	            << pipe_head_loss(pp, Q, network.fluid) +
186	                   minor_loss(pp, Q, network.fluid)
187	            << "\n";
188	    }
189	}
190	
191	} // namespace pipeflow
192
Let me check the example, main, and CMakeLists.

/opt/pipeflow/examples/two_loop_network.net

contents
1	# Two-loop water-distribution network fed by one elevated reservoir.
2	#
3	# A reservoir at 100 m of head (node 0) feeds a grid of commercial-steel mains
4	# (eps = 0.045 mm). Three interior junctions draw demand; the looped topology
5	# means flow can reach each demand by more than one path, so the split is set
6	# by the simultaneous continuity + Darcy-Weisbach/Colebrook balance.
7	#
8	#   0 (reservoir, H = 100 m)
9	#   |  p0
10	#   1 ---- p1 ---- 2
11	#   |              |
12	#   p2             p4
13	#   |     p5       |
14	#   3 ------------ 4
15	#
16	# Two independent loops: {p1,p4,p5,p2} and {p2,p5,p3} share interior links.
17	# Demands (m^3/s) sum to 0.30 = the reservoir supply.
18	
19	fluid     998.0  1.002e-3  9.80665
20	
21	node 0 reservoir 100.0
22	node 1 demand    0.00
23	node 2 demand    0.10
24	node 3 demand    0.08
25	node 4 demand    0.12
26	
27	# pipe  from to   D[m]   L[m]    eps[m]
28	pipe 0 1   0.30  300.0  4.5e-5
29	pipe 1 2   0.20  400.0  4.5e-5
30	pipe 1 3   0.20  400.0  4.5e-5
31	pipe 3 4   0.15  350.0  4.5e-5
32	pipe 2 4   0.15  350.0  4.5e-5
33	pipe 3 2   0.10  300.0  4.5e-5
34

/opt/pipeflow/src/main.cpp

contents
1	#include <iostream>
2	
3	#include "pipeflow/io.hpp"
4	
5	// Command-line demo driver: read a .net network scenario, solve the steady
6	// hydraulic state (junction heads + pipe flows), and print a report.
7	//   pipeflow_cli <scenario.net>
8	int main(int argc, char** argv) {
9	    if (argc != 2) {
10	        std::cerr << "usage: " << argv[0] << " <scenario.net>\n";
11	        return 2;
12	    }
13	    try {
14	        pipeflow::Network net = pipeflow::parse_network_file(argv[1]);
15	        pipeflow::write_report(std::cout, net);
16	    } catch (const std::exception& ex) {
17	        std::cerr << "error: " << ex.what() << "\n";
18	        return 1;
19	    }
20	    return 0;
21	}
22

/opt/pipeflow/tests/CMakeLists.txt

contents
1	add_executable(test_smoke test_smoke.cpp)
2	target_link_libraries(test_smoke PRIVATE pipeflow)
3	target_include_directories(test_smoke PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
4	add_test(NAME smoke COMMAND test_smoke)
5

/opt/pipeflow/CMakeLists.txt

contents
1	cmake_minimum_required(VERSION 3.16)
2	project(pipeflow LANGUAGES CXX)
3	
4	set(CMAKE_CXX_STANDARD 17)
5	set(CMAKE_CXX_STANDARD_REQUIRED ON)
6	set(CMAKE_CXX_EXTENSIONS OFF)
7	
8	if(NOT CMAKE_BUILD_TYPE)
9	  set(CMAKE_BUILD_TYPE Release)
10	endif()
11	
12	add_compile_options(-Wall -Wextra)
13	
14	# --- Core library -----------------------------------------------------------
15	# src/kernel.cpp, src/types.cpp and src/io.cpp are complete framework support
16	# code; src/solver.cpp ships as a stub for the candidate to implement.
17	add_library(pipeflow
18	  src/types.cpp
19	  src/kernel.cpp
20	  src/solver.cpp
21	  src/io.cpp
22	)
23	target_include_directories(pipeflow PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)
24	
25	# --- Demo CLI ---------------------------------------------------------------
26	add_executable(pipeflow_cli src/main.cpp)
27	target_link_libraries(pipeflow_cli PRIVATE pipeflow)
28	
29	# --- Tests ------------------------------------------------------------------
30	enable_testing()
31	add_subdirectory(tests)
32
I now understand the full API and physics. Let me check git/CLAUDE.md context and any memory, then implement.

Check docs, memory, feature usage

shell
cat /opt/pipeflow/CLAUDE.md 2>/dev/null; ls /logs/agent/sessions/projects/-opt-pipeflow/memory/ 2>/dev/null; echo "---grep features---"; grep -rn "emitter\|check_valve\|elevation" /opt/pipeflow/include /opt/pipeflow/src 2>/dev/null | grep -iv "validate\|//"
output
---grep features---
/opt/pipeflow/include/pipeflow/types.hpp:50:         double roughness, double minor_K = 0.0, bool check_valve = false,
/opt/pipeflow/include/pipeflow/types.hpp:60:    bool check_valve() const { return check_valve_; }
/opt/pipeflow/include/pipeflow/types.hpp:87:    bool check_valve_;
/opt/pipeflow/include/pipeflow/types.hpp:106:    double elevation{0.0};    
/opt/pipeflow/include/pipeflow/types.hpp:107:    double emitter_coeff{0.0}; 
/opt/pipeflow/include/pipeflow/types.hpp:108:    bool is_emitter{false};   
/opt/pipeflow/src/io.cpp:37:        bool check_valve{false};
/opt/pipeflow/src/io.cpp:84:                    if (!(ls >> nd.elevation)) {
/opt/pipeflow/src/io.cpp:85:                        fail(line_no, "'elev' needs a numeric elevation");
/opt/pipeflow/src/io.cpp:110:                    rp.check_valve = true;
/opt/pipeflow/src/io.cpp:143:                                   rp.minor_K, rp.check_valve, rp.minor_K_rev);
/opt/pipeflow/src/io.cpp:177:            << nd.elevation << "\n";
/opt/pipeflow/src/types.cpp:24:           double roughness, double minor_K, bool check_valve,
/opt/pipeflow/src/types.cpp:33:      check_valve_(check_valve) {
/opt/pipeflow/src/types.cpp:104:        if (nodes[i].emitter_coeff < 0.0) {
/opt/pipeflow/src/types.cpp:107:                " has negative emitter coefficient");

[stdout]
---grep features---
/opt/pipeflow/include/pipeflow/types.hpp:50:         double roughness, double minor_K = 0.0, bool check_valve = false,
/opt/pipeflow/include/pipeflow/types.hpp:60:    bool check_valve() const { return check_valve_; }
/opt/pipeflow/include/pipeflow/types.hpp:87:    bool check_valve_;
/opt/pipeflow/include/pipeflow/types.hpp:106:    double elevation{0.0};    
/opt/pipeflow/include/pipeflow/types.hpp:107:    double emitter_coeff{0.0}; 
/opt/pipeflow/include/pipeflow/types.hpp:108:    bool is_emitter{false};   
/opt/pipeflow/src/io.cpp:37:        bool check_valve{false};
/opt/pipeflow/src/io.cpp:84:                    if (!(ls >> nd.elevation)) {
/opt/pipeflow/src/io.cpp:85:                        fail(line_no, "'elev' needs a numeric elevation");
/opt/pipeflow/src/io.cpp:110:                    rp.check_valve = true;
/opt/pipeflow/src/io.cpp:143:                                   rp.minor_K, rp.check_valve, rp.minor_K_rev);
/opt/pipeflow/src/io.cpp:177:            << nd.elevation << "\n";
/opt/pipeflow/src/types.cpp:24:           double roughness, double minor_K, bool check_valve,
/opt/pipeflow/src/types.cpp:33:      check_valve_(check_valve) {
/opt/pipeflow/src/types.cpp:104:        if (nodes[i].emitter_coeff < 0.0) {
/opt/pipeflow/src/types.cpp:107:                " has negative emitter coefficient");
The IO parser handles elevation, check valves, and directional minor losses; emitters are set programmatically. I'll implement a full Global Gradient (Newton) solver handling all features. Let me write it.
write · /opt/pipeflow/src/solver.cpp
#include "pipeflow/solver.hpp"

#include <cmath>
#include <cstddef>
#include <stdexcept>
#include <vector>

#include "pipeflow/types.hpp"

namespace pipeflow {

// Steady-state hydraulic network solver.
//
// Unknowns are the volumetric flow Q_p in every pipe (positive = from->to) and
// the piezometric (total) head H_n at every junction; reservoir heads are fixed
// boundary data. Two physical laws close the system:
//
//   * Energy, one equation per pipe p (from u to v):
//         h_p(Q_p) = H_u - H_v
//     where h_p is the shipped Darcy-Weisbach friction loss plus the
//     directional minor-loss fitting term (both signed, odd in Q).
//
//   * Continuity, one equation per junction n (net inflow balances outflow):
//         sum_p C_{p,n} Q_p + demand_n + emitter_n(H_n) = 0,
//     with C_{p,n} = +1 if n == from(p), -1 if n == to(p). A pressure-driven
//     emitter draws q = K * sqrt(H_n - z_n) using the static elevation lift
//     (pressure head = total head minus node elevation).
//
// The coupled nonlinear system is solved with a damped Newton (global gradient)
// iteration: at each step the full sparse-structured Jacobian is assembled dense
// and solved by Gaussian elimination with partial pivoting, then a backtracking
// line search on the squared residual guarantees a monotone decrease.

namespace {

// A closed check valve must sustain reverse head with ~zero flow. Modelling it
// as a very large extra resistance for Q < 0 keeps the Jacobian non-singular
// (no topology changes) while driving any back-flow to a negligible level.
constexpr double kCheckValveResistance = 1e9;

// Floor on the pressure head used inside the emitter square-root so its
// derivative stays finite as the pressure approaches zero.
constexpr double kEmitterPressureFloor = 1e-9;

// Signed pipe head loss h_p(Q) = friction + directional minor loss, augmented
// with the check-valve reverse-flow penalty.
double pipe_loss(const Pipe& pipe, double Q, const Fluid& fluid) {
    double h = pipe_head_loss(pipe, Q, fluid) + minor_loss(pipe, Q, fluid);
    if (pipe.check_valve() && Q < 0.0) h += kCheckValveResistance * Q;
    return h;
}

// d h_p / dQ. Both shipped derivatives return the (positive, even) slope of the
// loss magnitude, which equals dh/dQ because h is odd.
double pipe_loss_deriv(const Pipe& pipe, double Q, const Fluid& fluid) {
    double d = pipe_head_loss_deriv(pipe, Q, fluid) +
               minor_loss_deriv(pipe, Q, fluid);
    if (pipe.check_valve() && Q < 0.0) d += kCheckValveResistance;
    return d;
}

// Pressure-driven emitter outflow and its derivative w.r.t. the node head.
// q = K * sqrt(max(H - z, 0)); no flow (and no slope) under zero gauge pressure.
double emitter_flow(const Node& nd, double H) {
    if (!nd.is_emitter || nd.emitter_coeff == 0.0) return 0.0;
    const double p = H - nd.elevation;
    if (p <= 0.0) return 0.0;
    return nd.emitter_coeff * std::sqrt(p);
}

double emitter_deriv(const Node& nd, double H) {
    if (!nd.is_emitter || nd.emitter_coeff == 0.0) return 0.0;
    const double p = H - nd.elevation;
    if (p <= 0.0) return 0.0;
    return 0.5 * nd.emitter_coeff / std::sqrt(std::max(p, kEmitterPressureFloor));
}

// Dense Gaussian elimination with partial pivoting. Solves A x = b in place;
// A is row-major m*m, b is length m and receives the solution. Returns false if
// the matrix is numerically singular.
bool solve_dense(std::vector<double>& A, std::vector<double>& b, std::size_t m) {
    for (std::size_t col = 0; col < m; ++col) {
        // Pivot: largest magnitude in this column at or below the diagonal.
        std::size_t piv = col;
        double best = std::fabs(A[col * m + col]);
        for (std::size_t r = col + 1; r < m; ++r) {
            const double v = std::fabs(A[r * m + col]);
            if (v > best) {
                best = v;
                piv = r;
            }
        }
        if (best == 0.0) return false;
        if (piv != col) {
            for (std::size_t c = 0; c < m; ++c)
                std::swap(A[col * m + c], A[piv * m + c]);
            std::swap(b[col], b[piv]);
        }
        const double diag = A[col * m + col];
        for (std::size_t r = col + 1; r < m; ++r) {
            const double factor = A[r * m + col] / diag;
            if (factor == 0.0) continue;
            for (std::size_t c = col; c < m; ++c)
                A[r * m + c] -= factor * A[col * m + c];
            b[r] -= factor * b[col];
        }
    }
    // Back substitution.
    for (std::size_t i = m; i-- > 0;) {
        double s = b[i];
        for (std::size_t c = i + 1; c < m; ++c) s -= A[i * m + c] * b[c];
        b[i] = s / A[i * m + i];
    }
    return true;
}

} // namespace

Solution NetworkSolver::solve() const {
    network_.validate();

    const Fluid& fluid = network_.fluid;
    const std::size_t np = network_.pipe_count();
    const std::size_t nn = network_.node_count();

    // Map every junction node to a compact unknown-head index; reservoirs (-1)
    // keep their fixed head and contribute no continuity equation.
    std::vector<std::ptrdiff_t> jidx(nn, -1);
    std::size_t nj = 0;
    double reservoir_head_sum = 0.0;
    for (std::size_t n = 0; n < nn; ++n) {
        if (network_.nodes[n].is_reservoir) {
            reservoir_head_sum += network_.nodes[n].head;
        } else {
            jidx[n] = static_cast<std::ptrdiff_t>(nj++);
        }
    }
    const std::size_t nres = nn - nj;
    const double mean_res_head =
        nres > 0 ? reservoir_head_sum / static_cast<double>(nres) : 0.0;

    // Unknown vector x = [ Q_0..Q_{np-1}, H_j0..H_j{nj-1} ].
    const std::size_t m = np + nj;
    std::vector<double> x(m, 0.0);

    // Initialise pipe flows to ~1 m/s forward (keeps the first step out of the
    // degenerate zero-flow slope) and junction heads to the mean reservoir head.
    for (std::size_t p = 0; p < np; ++p) {
        x[p] = network_.pipes[p].area() * 1.0;
    }
    for (std::size_t n = 0; n < nn; ++n) {
        if (jidx[n] >= 0) x[np + static_cast<std::size_t>(jidx[n])] = mean_res_head;
    }

    auto head_of = [&](std::size_t n) -> double {
        const Node& nd = network_.nodes[n];
        if (nd.is_reservoir) return nd.head;
        return x[np + static_cast<std::size_t>(jidx[n])];
    };

    // Residual R(x): energy rows [0,np), continuity rows [np, np+nj).
    auto residual = [&](const std::vector<double>& xv) {
        std::vector<double> R(m, 0.0);
        auto H = [&](std::size_t n) -> double {
            const Node& nd = network_.nodes[n];
            return nd.is_reservoir ? nd.head
                                   : xv[np + static_cast<std::size_t>(jidx[n])];
        };
        for (std::size_t p = 0; p < np; ++p) {
            const Pipe& pipe = network_.pipes[p];
            const double Q = xv[p];
            R[p] = pipe_loss(pipe, Q, fluid) - (H(pipe.from()) - H(pipe.to()));
        }
        for (std::size_t p = 0; p < np; ++p) {
            const Pipe& pipe = network_.pipes[p];
            const double Q = xv[p];
            const std::ptrdiff_t jf = jidx[pipe.from()];
            const std::ptrdiff_t jt = jidx[pipe.to()];
            if (jf >= 0) R[np + static_cast<std::size_t>(jf)] += Q;
            if (jt >= 0) R[np + static_cast<std::size_t>(jt)] -= Q;
        }
        for (std::size_t n = 0; n < nn; ++n) {
            if (jidx[n] < 0) continue;
            const Node& nd = network_.nodes[n];
            R[np + static_cast<std::size_t>(jidx[n])] +=
                nd.demand + emitter_flow(nd, H(n));
        }
        return R;
    };

    auto norm2 = [](const std::vector<double>& v) {
        double s = 0.0;
        for (double e : v) s += e * e;
        return s;
    };
    auto norm_inf = [](const std::vector<double>& v) {
        double s = 0.0;
        for (double e : v) s = std::max(s, std::fabs(e));
        return s;
    };

    const double tol = options_.tolerance;
    const double min_damping = options_.min_damping;
    const int max_iter = options_.max_iterations;

    std::vector<double> R = residual(x);
    int iter = 0;
    bool converged = norm_inf(R) <= tol;

    while (!converged && iter < max_iter) {
        // Assemble the dense Jacobian J (m x m, row-major).
        std::vector<double> J(m * m, 0.0);
        for (std::size_t p = 0; p < np; ++p) {
            const Pipe& pipe = network_.pipes[p];
            const double Q = x[p];
            // Energy row p: d/dQ_p, and -d(H_from - H_to) for junction heads.
            J[p * m + p] = pipe_loss_deriv(pipe, Q, fluid);
            const std::ptrdiff_t jf = jidx[pipe.from()];
            const std::ptrdiff_t jt = jidx[pipe.to()];
            if (jf >= 0) J[p * m + (np + static_cast<std::size_t>(jf))] -= 1.0;
            if (jt >= 0) J[p * m + (np + static_cast<std::size_t>(jt))] += 1.0;
            // Continuity rows: dC^T Q / dQ_p = C_{p,n}.
            if (jf >= 0)
                J[(np + static_cast<std::size_t>(jf)) * m + p] += 1.0;
            if (jt >= 0)
                J[(np + static_cast<std::size_t>(jt)) * m + p] -= 1.0;
        }
        for (std::size_t n = 0; n < nn; ++n) {
            if (jidx[n] < 0) continue;
            const std::size_t row = np + static_cast<std::size_t>(jidx[n]);
            J[row * m + row] += emitter_deriv(network_.nodes[n], head_of(n));
        }

        // Solve J * dx = -R.
        std::vector<double> rhs(m);
        for (std::size_t i = 0; i < m; ++i) rhs[i] = -R[i];
        if (!solve_dense(J, rhs, m)) break;  // singular: stop, report state.

        // Backtracking line search on the squared residual.
        const double f0 = norm2(R);
        double alpha = 1.0;
        std::vector<double> xn(m), Rn;
        while (true) {
            for (std::size_t i = 0; i < m; ++i) xn[i] = x[i] + alpha * rhs[i];
            Rn = residual(xn);
            if (norm2(Rn) < f0 || alpha <= min_damping) break;
            alpha *= 0.5;
        }

        x.swap(xn);
        R.swap(Rn);
        ++iter;
        converged = norm_inf(R) <= tol;
    }

    // Largest absolute nodal flow imbalance (m^3/s) over the continuity rows.
    double cont_residual = 0.0;
    for (std::size_t j = 0; j < nj; ++j)
        cont_residual = std::max(cont_residual, std::fabs(R[np + j]));

    Solution sol;
    sol.pipe_flow.assign(np, 0.0);
    for (std::size_t p = 0; p < np; ++p) sol.pipe_flow[p] = x[p];
    sol.node_head.assign(nn, 0.0);
    for (std::size_t n = 0; n < nn; ++n) sol.node_head[n] = head_of(n);

    sol.report.iterations = iter;
    sol.report.residual = cont_residual;
    sol.report.converged = converged;
    return sol;
}

} // namespace pipeflow
Let me add the missing includes for `std::max`/`std::swap`, then build and test.

/opt/pipeflow/src/solver.cpp

− removed
#include <cmath>
#include <cstddef>
#include <stdexcept>
#include <vector>
+ added
#include <algorithm>
#include <cmath>
#include <cstddef>
#include <utility>
#include <vector>

Configure, build, run tests

shell
cmake -S . -B build -DCMAKE_BUILD_TYPE=Release >/tmp/cm.log 2>&1 && cmake --build build --parallel >/tmp/build.log 2>&1 && echo BUILD_OK && cd build && ctest --output-on-failure 2>&1 | tail -20
output
Exit code 2

[error] tool reported failure

Show build errors

shell
tail -30 /tmp/cm.log; echo "===BUILD==="; tail -40 /tmp/build.log
output
-- The CXX compiler identification is GNU 11.4.0
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /opt/pipeflow/build
===BUILD===
[ 11%] Building CXX object CMakeFiles/pipeflow.dir/src/types.cpp.o
[ 22%] Building CXX object CMakeFiles/pipeflow.dir/src/solver.cpp.o
[ 33%] Building CXX object CMakeFiles/pipeflow.dir/src/kernel.cpp.o
[ 44%] Building CXX object CMakeFiles/pipeflow.dir/src/io.cpp.o
[ 55%] Linking CXX static library libpipeflow.a
[ 55%] Built target pipeflow
[ 66%] Building CXX object CMakeFiles/pipeflow_cli.dir/src/main.cpp.o
[ 77%] Building CXX object tests/CMakeFiles/test_smoke.dir/test_smoke.cpp.o
[ 88%] Linking CXX executable pipeflow_cli
/usr/bin/ld: libpipeflow.a(io.cpp.o): in function `pipeflow::write_report(std::ostream&, pipeflow::Network const&)':
io.cpp:(.text+0x221): undefined reference to `pipeflow::NetworkSolver::NetworkSolver(pipeflow::Network const&, pipeflow::SolverOptions const&)'
collect2: error: ld returned 1 exit status
gmake[2]: *** [CMakeFiles/pipeflow_cli.dir/build.make:98: pipeflow_cli] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:128: CMakeFiles/pipeflow_cli.dir/all] Error 2
gmake[1]: *** Waiting for unfinished jobs....
[100%] Linking CXX executable test_smoke
/usr/bin/ld: CMakeFiles/test_smoke.dir/test_smoke.cpp.o: in function `pipeflow_test_fn_22()':
test_smoke.cpp:(.text+0x46e): undefined reference to `pipeflow::NetworkSolver::NetworkSolver(pipeflow::Network const&, pipeflow::SolverOptions const&)'
/usr/bin/ld: CMakeFiles/test_smoke.dir/test_smoke.cpp.o: in function `pipeflow_test_fn_9()':
test_smoke.cpp:(.text+0x71b): undefined reference to `pipeflow::NetworkSolver::NetworkSolver(pipeflow::Network const&, pipeflow::SolverOptions const&)'
collect2: error: ld returned 1 exit status
gmake[2]: *** [tests/CMakeFiles/test_smoke.dir/build.make:98: tests/test_smoke] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:154: tests/CMakeFiles/test_smoke.dir/all] Error 2
gmake: *** [Makefile:101: all] Error 2

[stdout]
-- The CXX compiler identification is GNU 11.4.0
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /opt/pipeflow/build
===BUILD===
[ 11%] Building CXX object CMakeFiles/pipeflow.dir/src/types.cpp.o
[ 22%] Building CXX object CMakeFiles/pipeflow.dir/src/solver.cpp.o
[ 33%] Building CXX object CMakeFiles/pipeflow.dir/src/kernel.cpp.o
[ 44%] Building CXX object CMakeFiles/pipeflow.dir/src/io.cpp.o
[ 55%] Linking CXX static library libpipeflow.a
[ 55%] Built target pipeflow
[ 66%] Building CXX object CMakeFiles/pipeflow_cli.dir/src/main.cpp.o
[ 77%] Building CXX object tests/CMakeFiles/test_smoke.dir/test_smoke.cpp.o
[ 88%] Linking CXX executable pipeflow_cli
/usr/bin/ld: libpipeflow.a(io.cpp.o): in function `pipeflow::write_report(std::ostream&, pipeflow::Network const&)':
io.cpp:(.text+0x221): undefined reference to `pipeflow::NetworkSolver::NetworkSolver(pipeflow::Network const&, pipeflow::SolverOptions const&)'
collect2: error: ld returned 1 exit status
gmake[2]: *** [CMakeFiles/pipeflow_cli.dir/build.make:98: pipeflow_cli] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:128: CMakeFiles/pipeflow_cli.dir/all] Error 2
gmake[1]: *** Waiting for unfinished jobs....
[100%] Linking CXX executable test_smoke
/usr/bin/ld: CMakeFiles/test_smoke.dir/test_smoke.cpp.o: in function `pipeflow_test_fn_22()':
test_smoke.cpp:(.text+0x46e): undefined reference to `pipeflow::NetworkSolver::NetworkSolver(pipeflow::Network const&, pipeflow::SolverOptions const&)'
/usr/bin/ld: CMakeFiles/test_smoke.dir/test_smoke.cpp.o: in function `pipeflow_test_fn_9()':
test_smoke.cpp:(.text+0x71b): undefined reference to `pipeflow::NetworkSolver::NetworkSolver(pipeflow::Network const&, pipeflow::SolverOptions const&)'
collect2: error: ld returned 1 exit status
gmake[2]: *** [tests/CMakeFiles/test_smoke.dir/build.make:98: tests/test_smoke] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:154: tests/CMakeFiles/test_smoke.dir/all] Error 2
gmake: *** [Makefile:101: all] Error 2
I accidentally dropped the constructor definition when rewriting. Let me add it back.

/opt/pipeflow/src/solver.cpp

− removed
} // namespace

Solution NetworkSolver::solve() const {
+ added
} // namespace

NetworkSolver::NetworkSolver(const Network& network,
                             const SolverOptions& options)
    : network_(network), options_(options) {}

Solution NetworkSolver::solve() const {

Rebuild and run tests

shell
cmake --build build --parallel >/tmp/build.log 2>&1 && echo BUILD_OK && cd build && ctest --output-on-failure 2>&1 | tail -20 || (echo "===FAIL==="; tail -30 /tmp/build.log)
output
BUILD_OK
Test project /opt/pipeflow/build
    Start 1: smoke
1/1 Test #1: smoke ............................   Passed    0.00 sec

100% tests passed, 0 tests failed out of 1

Total Test time (real) =   0.01 sec

[stdout]
BUILD_OK
Test project /opt/pipeflow/build
    Start 1: smoke
1/1 Test #1: smoke ............................   Passed    0.00 sec

100% tests passed, 0 tests failed out of 1

Total Test time (real) =   0.01 sec
Build is clean (no warnings) and the test passes. Let me verify the solver produces physically correct results on the two-loop example, and sanity-check conservation, energy balance, and an emitter/elevation case.

Run CLI on two-loop example

shell
cd /opt/pipeflow && ./build/pipeflow_cli examples/two_loop_network.net
output
# pipe-network (continuity + Darcy/Colebrook + directional fittings) report
converged=yes iterations=9 residual=2.775558e-17 m^3/s
# nodes: id  type        head[m]      demand[m^3/s]  elev[m]
node 0  reservoir   1.000000e+02  0.000000e+00  0.000000e+00
node 1  junction    8.723839e+01  0.000000e+00  0.000000e+00
node 2  junction    5.136666e+01  1.000000e-01  0.000000e+00
node 3  junction    5.341509e+01  8.000000e-02  0.000000e+00
node 4  junction    3.008056e+01  1.200000e-01  0.000000e+00
# pipes: from->to   Q[m^3/s]     V[m/s]       head_loss[m]
pipe 0->1  3.000000e-01  4.244132e+00  1.276161e+01
pipe 1->2  1.522662e-01  4.846783e+00  3.587173e+01
pipe 1->3  1.477338e-01  4.702514e+00  3.382330e+01
pipe 3->4  6.142734e-02  3.476077e+00  2.333453e+01
pipe 2->4  5.857266e-02  3.314534e+00  2.128610e+01
pipe 3->2  6.306482e-03  8.029662e-01  2.048424e+00

[stdout]
# pipe-network (continuity + Darcy/Colebrook + directional fittings) report
converged=yes iterations=9 residual=2.775558e-17 m^3/s
# nodes: id  type        head[m]      demand[m^3/s]  elev[m]
node 0  reservoir   1.000000e+02  0.000000e+00  0.000000e+00
node 1  junction    8.723839e+01  0.000000e+00  0.000000e+00
node 2  junction    5.136666e+01  1.000000e-01  0.000000e+00
node 3  junction    5.341509e+01  8.000000e-02  0.000000e+00
node 4  junction    3.008056e+01  1.200000e-01  0.000000e+00
# pipes: from->to   Q[m^3/s]     V[m/s]       head_loss[m]
pipe 0->1  3.000000e-01  4.244132e+00  1.276161e+01
pipe 1->2  1.522662e-01  4.846783e+00  3.587173e+01
pipe 1->3  1.477338e-01  4.702514e+00  3.382330e+01
pipe 3->4  6.142734e-02  3.476077e+00  2.333453e+01
pipe 2->4  5.857266e-02  3.314534e+00  2.128610e+01
pipe 3->2  6.306482e-03  8.029662e-01  2.048424e+00
Conservation and energy balance both check out perfectly. Let me verify the emitter, elevation, and check-valve code paths converge sanely with a quick standalone test.

Test emitter, elevation, check valve paths

shell
cat > /tmp/t.cpp <<'EOF'
#include <cstdio>
#include <cmath>
#include "pipeflow/solver.hpp"
using namespace pipeflow;
int main(){
  // Emitter + elevation: reservoir 0 -> junction 1 (emitter, elev 5)
  {
    Network net; net.fluid=Fluid{998.0,1.002e-3,9.80665};
    Node a{0,true,30.0,0.0}; Node b; b.id=1; b.is_emitter=true; b.emitter_coeff=0.05; b.elevation=5.0;
    net.nodes={a,b}; net.pipes={Pipe(0,1,0.2,200.0,4.5e-5)};
    auto s=NetworkSolver(net).solve();
    double q=s.pipe_flow[0]; double H=s.node_head[1];
    double emit=0.05*std::sqrt(H-5.0);
    printf("emitter: conv=%d iter=%d Q=%.6f H1=%.4f emit=%.6f imbalance=%.2e\n",
      s.report.converged,s.report.iterations,q,H,emit,q-emit);
  }
  // Check valve: two reservoirs, low->high would reverse; CV blocks it
  {
    Network net; net.fluid=Fluid{998.0,1.002e-3,9.80665};
    net.nodes={Node{0,true,10.0,0.0},Node{1,true,20.0,0.0}};
    net.pipes={Pipe(0,1,0.15,250.0,4.5e-5,0.0,true)}; // check valve, from 0(low) to 1(high)
    auto s=NetworkSolver(net).solve();
    printf("checkvalve(blocked): conv=%d iter=%d Q=%.3e (should be ~0)\n",
      s.report.converged,s.report.iterations,s.pipe_flow[0]);
  }
  // Check valve allowing forward flow
  {
    Network net; net.fluid=Fluid{998.0,1.002e-3,9.80665};
    net.nodes={Node{0,true,20.0,0.0},Node{1,true,10.0,0.0}};
    net.pipes={Pipe(0,1,0.15,250.0,4.5e-5,0.0,true)};
    auto s=NetworkSolver(net).solve();
    printf("checkvalve(open): conv=%d iter=%d Q=%.6f (should be >0)\n",
      s.report.converged,s.report.iterations,s.pipe_flow[0]);
  }
  return 0;
}
EOF
g++ -std=c++17 -Iinclude /tmp/t.cpp build/libpipeflow.a -o /tmp/t && /tmp/t
output
emitter: conv=1 iter=15 Q=0.145839 H1=13.5076 emit=0.145839 imbalance=0.00e+00
checkvalve(blocked): conv=1 iter=3 Q=-1.000e-08 (should be ~0)
checkvalve(open): conv=1 iter=5 Q=0.047113 (should be >0)

[stdout]
emitter: conv=1 iter=15 Q=0.145839 H1=13.5076 emit=0.145839 imbalance=0.00e+00
checkvalve(blocked): conv=1 iter=3 Q=-1.000e-08 (should be ~0)
checkvalve(open): conv=1 iter=5 Q=0.047113 (should be >0)
All feature paths work correctly: - **Emitter + elevation**: pipe inflow exactly matches pressure-driven outflow `K·√(H−z)`; mass balance closes to machine zero. - **Check valve (reverse)**: flow driven to ~0 (−1e-8) instead of letting the low reservoir back-feed the high one. - **Check valve (forward)**: normal positive flow. Let me clean up the scratch files.

Remove temp files

shell
rm -f /tmp/t.cpp /tmp/t /tmp/cm.log /tmp/build.log
output
(Bash completed with no output)
Done. `NetworkSolver::solve()` is implemented in `/opt/pipeflow/src/solver.cpp` , the project builds with no warnings and the test suite passes (`1/1`). ## What I implemented A **damped Newton (global gradient) solver** for the coupled steady-state system, using only the shipped kernel primitives (no public signatures touched): - **Unknowns**: pipe flows `Q_p` (positive = from→to) and junction piezometric heads `H_n`; reservoir heads are fixed boundary data. - **Energy law** (one eq/pipe): `pipe_head_loss + minor_loss = H_from − H_to`, using the shipped signed friction + directional minor-loss primitives. - **Continuity** (one eq/junction): `Σ C_{p,n}·Q_p + demand_n + emitter_n(H_n) = 0`. - **Emitter**: pressure-driven outflow `K·√(H_n − z_n)` , this is where the static elevation lift (total head → gauge pressure) enters. - **Check valves**: modeled as a large reverse-flow resistance, so a closed valve sustains back-head with ~zero flow without changing topology (keeps the Jacobian non-singular). Each iteration assembles the full Jacobian dense and solves it via Gaussian elimination with partial pivoting, followed by a backtracking line search on the squared residual to guarantee monotone descent. Convergence and `min_damping`/`tolerance`/`max_iterations` come from `SolverOptions`. ## Verification - **Two-loop example**: converges in 9 iterations, residual ~1e-17; I hand-checked mass balance at every node and the energy balance around the loops , all consistent. - **Standalone checks** for the parser-untested paths (emitter, elevation, both check-valve directions): all converge with correct, physically sensible results. The only file changed is `src/solver.cpp`.
Final diff , what the agent changed

No file changes, the agent left the workspace untouched.

Verifier output , the proof behind the reward
tests/test.sh
== Restoring pristine project ==
== Staging candidate solver ==
== Injecting hidden grading tests ==
== Configuring (cmake) ==
-- The CXX compiler identification is GNU 11.4.0
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /tmp/tmp.EShhxv4kGU/pipeflow/build_grade
== Building ==
[  5%] Building CXX object CMakeFiles/pipeflow.dir/src/types.cpp.o
[ 10%] Building CXX object CMakeFiles/pipeflow.dir/src/kernel.cpp.o
[ 15%] Building CXX object CMakeFiles/pipeflow.dir/src/solver.cpp.o
[ 21%] Building CXX object CMakeFiles/pipeflow.dir/src/io.cpp.o
[ 26%] Linking CXX static library libpipeflow.a
[ 26%] Built target pipeflow
[ 31%] Building CXX object CMakeFiles/pipeflow_cli.dir/src/main.cpp.o
[ 36%] Building CXX object tests/CMakeFiles/test_minor.dir/test_minor.cpp.o
[ 42%] Building CXX object tests/CMakeFiles/test_kernel.dir/test_kernel.cpp.o
[ 47%] Building CXX object tests/CMakeFiles/test_analytic.dir/test_analytic.cpp.o
[ 52%] Building CXX object tests/CMakeFiles/test_valves.dir/test_valves.cpp.o
[ 57%] Building CXX object tests/CMakeFiles/test_exceptions.dir/test_exceptions.cpp.o
[ 63%] Building CXX object tests/CMakeFiles/test_soak.dir/test_soak.cpp.o
[ 68%] Linking CXX executable pipeflow_cli
[ 68%] Built target pipeflow_cli
[ 73%] Linking CXX executable test_exceptions
[ 73%] Built target test_exceptions
[ 78%] Linking CXX executable test_kernel
[ 78%] Built target test_kernel
[ 84%] Linking CXX executable test_minor
[ 89%] Linking CXX executable test_valves
[ 89%] Built target test_minor
[ 94%] Linking CXX executable test_soak
[ 94%] Built target test_valves
[100%] Linking CXX executable test_analytic
[100%] Built target test_soak
[100%] Built target test_analytic
== Running hidden tests ==
Test project /tmp/tmp.EShhxv4kGU/pipeflow/build_grade
    Start 1: test_kernel
1/6 Test #1: test_kernel ......................   Passed    0.00 sec
    Start 2: test_analytic
2/6 Test #2: test_analytic ....................***Failed    0.00 sec
[ PASS ] single_pipe_two_reservoirs
[ PASS ] single_pipe_with_minor_K
[ FAIL ] series_continuity_and_head_sum: edge energy residual within tolerance
[ PASS ] parallel_equal_total_head_loss
[ FAIL ] cross_check_vs_oracle_small: edge energy residual within tolerance
[ FAIL ] static_lift_sign_loop: edge energy residual within tolerance
[ FAIL ] degenerate_zero_head_edge: edge energy residual within tolerance
[ FAIL ] tri_reservoir_net: edge energy residual within tolerance
----
3/8 tests passed

    Start 3: test_minor
3/6 Test #3: test_minor .......................***Failed    0.00 sec
[ PASS ] minor_loss_changes_split
[ FAIL ] asymmetric_minor_reverse_leg: edge energy residual within tolerance
----
1/2 tests passed

    Start 4: test_valves
4/6 Test #4: test_valves ......................***Failed    0.01 sec
[ FAIL ] valve_loop_must_close: no reverse flow through the check valve
[ PASS ] valve_open_when_forward_helps
[ FAIL ] valve_coupled_active_set: edge energy residual within tolerance
[ FAIL ] valve_knife_edge: edge energy residual within tolerance
[ PASS ] valve_dead_leg
[ FAIL ] valve_wrong_active_set_trap: edge energy residual within tolerance
[ FAIL ] valve_complementarity_holds: check-valve complementarity within tolerance
----
2/7 tests passed

    Start 5: test_soak
5/6 Test #5: test_soak ........................***Failed    0.00 sec
[ FAIL ] soak_random_networks: edge energy residual within tolerance
[ FAIL ] soak_random_valve_networks: edge energy residual within tolerance
[ FAIL ] convergence_contract: edge energy residual within tolerance
----
0/3 tests passed

    Start 6: test_exceptions
6/6 Test #6: test_exceptions ..................   Passed    0.00 sec

33% tests passed, 4 tests failed out of 6

Label Time Summary:
hidden    =   0.02 sec*proc (6 tests)

Total Test time (real) =   0.02 sec

The following tests FAILED:
	  2 - test_analytic (Failed)
	  3 - test_minor (Failed)
	  4 - test_valves (Failed)
	  5 - test_soak (Failed)


Errors while running CTest
FAIL: hidden tests failed

Reproduce this trial: git checkout 2f94510 && PYTHONPATH=src python3 scripts/build_site.py , then open trial/trial_64b0a46969564093. Re-running the agent live requires EVAL_PLATFORM_ENABLE_OAUTH_SMOKE=1 and is non-deterministic.

Trial trial_64b0a46969564093 · verifier authoritative; classifier explanatory.