sepehr
3358b74342
Ship the Next.js cycle editor with CAD chrome, technical HX symbols, Fixed/Free boundary guidance, and secondary water/air pressure drop support in the solver stack. Co-authored-by: Cursor <cursoragent@cursor.com>
110 lines
3.4 KiB
Rust
110 lines
3.4 KiB
Rust
//! System-wide DoF balance tests.
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//!
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//! Verifies that the ledger counts equations and unknowns consistently and that
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//! `finalize` hard-fails on square-system violations.
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use entropyk_components::{Component, ComponentError, ConnectedPort, JacobianBuilder, ResidualVector, StateSlice};
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use entropyk_solver::dof::SystemDofBalance;
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use entropyk_solver::system::System;
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use entropyk_solver::TopologyError;
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/// Minimal mock: N residuals that are identically zero (topology bookkeeping only).
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struct MockEq {
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n: usize,
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}
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impl Component for MockEq {
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fn compute_residuals(
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&self,
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_state: &StateSlice,
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residuals: &mut ResidualVector,
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) -> Result<(), ComponentError> {
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for r in residuals.iter_mut().take(self.n) {
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*r = 0.0;
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}
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Ok(())
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}
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fn jacobian_entries(
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&self,
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_state: &StateSlice,
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_jacobian: &mut JacobianBuilder,
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) -> Result<(), ComponentError> {
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Ok(())
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}
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fn n_equations(&self) -> usize {
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self.n
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}
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fn get_ports(&self) -> &[ConnectedPort] {
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&[]
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}
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fn flow_paths(&self) -> Vec<(usize, usize)> {
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// Single-stream pass-through so the edge pair shares one ṁ branch.
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vec![(0, 1)]
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}
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}
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/// Two-node cycle with matching residual count → square after CM1.4.
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///
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/// Unknowns: 1 ṁ + 2 edges × (P,h) = 5
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/// Equations: 3 + 2 = 5
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#[test]
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fn two_node_cycle_is_balanced() {
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let mut sys = System::new();
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let a = sys.add_component(Box::new(MockEq { n: 3 }));
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let b = sys.add_component(Box::new(MockEq { n: 2 }));
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sys.add_edge(a, b).unwrap();
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sys.add_edge(b, a).unwrap();
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sys.finalize().expect("balanced system must finalize");
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let report = sys.dof_report();
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assert_eq!(report.n_unknowns, 5);
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assert_eq!(report.n_equations, 5);
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assert_eq!(report.balance, SystemDofBalance::Balanced);
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assert!(sys.validate_system_dof().is_ok());
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}
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/// One extra residual without a free unknown → over-constrained, finalize fails.
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#[test]
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fn overconstrained_finalize_fails() {
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let mut sys = System::new();
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let a = sys.add_component(Box::new(MockEq { n: 4 })); // +1 excess
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let b = sys.add_component(Box::new(MockEq { n: 2 }));
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sys.add_edge(a, b).unwrap();
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sys.add_edge(b, a).unwrap();
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// unknowns = 5, equations = 6
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let err = sys.finalize().expect_err("must reject over-constrained system");
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match err {
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TopologyError::DofImbalance { message } => {
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assert!(
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message.contains("over-constrained") || message.contains("equations"),
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"unexpected message: {message}"
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);
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}
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other => panic!("expected DofImbalance, got {other:?}"),
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}
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}
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/// Missing residual → under-constrained: finalize warns but allows topology tests;
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/// hard `validate_system_dof` still rejects (production path).
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#[test]
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fn underconstrained_detected_by_validate_system_dof() {
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let mut sys = System::new();
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let a = sys.add_component(Box::new(MockEq { n: 2 }));
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let b = sys.add_component(Box::new(MockEq { n: 2 }));
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sys.add_edge(a, b).unwrap();
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sys.add_edge(b, a).unwrap();
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// unknowns = 5, equations = 4
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sys.finalize()
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.expect("under-constrained allowed at finalize for topology mocks");
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let report = sys.dof_report();
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assert!(matches!(
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report.balance,
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SystemDofBalance::UnderConstrained { free_dofs: 1 }
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));
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assert!(sys.validate_system_dof().is_err());
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}
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