WIP: Sc/p4est view coupled hanging nodes

[SimonCan]

Added capability of coupling pest mesh views with hanging/non-conforming nodes.

[github-actions]

Review checklist

This checklist is meant to assist creators of PRs (to let them know what reviewers will typically look for) and reviewers (to guide them in a structured review process). Items do not need to be checked explicitly for a PR to be eligible for merging.

Purpose and scope

• The PR has a single goal that is clear from the PR title and/or description.
• All code changes represent a single set of modifications that logically belong together.
• No more than 500 lines of code are changed or there is no obvious way to split the PR into multiple PRs.

Code quality

• The code can be understood easily.
• Newly introduced names for variables etc. are self-descriptive and consistent with existing naming conventions.
• There are no redundancies that can be removed by simple modularization/refactoring.
• There are no leftover debug statements or commented code sections.
• The code adheres to our conventions and style guide, and to the Julia guidelines.

Documentation

• New functions and types are documented with a docstring or top-level comment.
• Relevant publications are referenced in docstrings (see example for formatting).
• Inline comments are used to document longer or unusual code sections.
• Comments describe intent ("why?") and not just functionality ("what?").
• If the PR introduces a significant change or new feature, it is documented in NEWS.md with its PR number.

Testing

• The PR passes all tests.
• New or modified lines of code are covered by tests.
• New or modified tests run in less then 10 seconds.

Performance

• There are no type instabilities or memory allocations in performance-critical parts.
• If the PR intent is to improve performance, before/after time measurements are posted in the PR.

Verification

• The correctness of the code was verified using appropriate tests.
• If new equations/methods are added, a convergence test has been run and the results
  are posted in the PR.

Created with ❤️ by the Trixi.jl community.

[codecov]

Codecov Report

❌ Patch coverage is 23.28358% with 514 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (sc/p4est-view-coupled-enhanced@cdd1181). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
src/solvers/dgsem_p4est/dg_2d_coupled.jl	0.00%	257 Missing ⚠️
src/meshes/p4est_mesh_view.jl	0.00%	140 Missing ⚠️
src/solvers/dgsem_p4est/containers_coupled.jl	0.00%	44 Missing ⚠️
...discretization/semidiscretization_coupled_p4est.jl	0.00%	43 Missing ⚠️
...dgsem/elixir_advection_coupled_with_amr_mortars.jl	0.00%	20 Missing ⚠️
src/solvers/dgsem_p4est/dg.jl	0.00%	4 Missing ⚠️
src/solvers/dgsem/basis_lobatto_legendre.jl	91.67%	2 Missing ⚠️
src/solvers/dgsem_p4est/dg_2d.jl	0.00%	2 Missing ⚠️
src/solvers/dgsem_p4est/dg_3d_parallel.jl	0.00%	1 Missing ⚠️
src/solvers/dgsem_tree/subcell_finite_volume_O2.jl	50.00%	1 Missing ⚠️

Additional details and impacted files

@@                        Coverage Diff                        @@
##             sc/p4est-view-coupled-enhanced    #2598   +/-   ##
=================================================================
  Coverage                                  ?   91.87%           
=================================================================
  Files                                     ?      570           
  Lines                                     ?    44734           
  Branches                                  ?        0           
=================================================================
  Hits                                      ?    41095           
  Misses                                    ?     3639           
  Partials                                  ?        0           

Flag	Coverage Δ
unittests	91.87% <23.28%> (?)

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[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Trixi.jl/test/test_p4est_2d.jl

Lines 121 to 125 in 776c7a8

	# Load the mesh file for code coverage.
	loaded_mesh = Trixi.load_mesh_serial(joinpath("out", "mesh_1_000000000.h5");
	n_cells_max = 0,
	RealT = typeof(parent_mesh).parameters[3])
	end

[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Suggested change

[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Suggested change

	@trixi_testset "elixir_advection_coupled_with_amr_mortars.jl" begin
	@test_trixi_include(joinpath(EXAMPLES_DIR,
	"elixir_advection_coupled_with_amr_mortars.jl"),
	tspan=(0.0, 1.0),
	l2=[0.0007319835742861697, 0.001985235435356559],
	linf=[0.008310493861112489, 0.009003928823673624])
	end
	@trixi_testset "elixir_advection_restart_amr.jl" begin
	@test_trixi_include(joinpath(EXAMPLES_DIR, "elixir_advection_restart_amr.jl"),
	l2=[2.869137983727866e-6],
	linf=[3.8353423270964804e-5])
	end

[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Suggested change

	@trixi_testset "elixir_advection_coupled_checkerboard_views.jl" begin
	@test_trixi_include(joinpath(EXAMPLES_DIR,
	"elixir_advection_coupled_checkerboard_views.jl"),
	tspan=(0.0, 1.0),
	l2=[0.0015361594792012185, 0.001455051112944291],
	linf=[0.00900392882367318, 0.008196871838623832])
	end
	@trixi_testset "elixir_advection_coupled.jl" begin
	@test_trixi_include(joinpath(EXAMPLES_DIR, "elixir_advection_coupled.jl"),
	l2=[0.00013318279010712176, 0.00013318279010712014],
	linf=[0.000960578229013187, 0.0009605782290140752])
	# Ensure that we do not have excessive memory allocations
	# (e.g., from type instabilities)
	@test_broken (@allocated Trixi.rhs!(du_ode, u_ode, semi, t)) < 1000
	# Test show methods for code coverage.
	@test_nowarn show(stdout, semi)
	# Load the mesh file for code coverage.
	loaded_mesh = Trixi.load_mesh_serial(joinpath("out", "mesh_1_000000000.h5");
	n_cells_max = 0,
	RealT = typeof(parent_mesh).parameters[3])
	end

[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Suggested change

	u[3], 0.0,
	u[4], 0.0,
	0.0, 0.0,
	0.0)
	u[3], 0.0,
	u[4], 0.0,
	0.0, 0.0,
	0.0)

[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Suggested change

	u[3], u[5])
	u[3], u[5])

[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Trixi.jl/test/test_p4est_2d.jl

Lines 151 to 160 in e85eab6

	@trixi_testset "elixir_advection_basic.jl" begin
	@test_trixi_include(joinpath(EXAMPLES_DIR, "elixir_advection_basic.jl"),
	# Expected errors are exactly the same as with P4estMeshView!
	l2=[0.00013773915040249946],
	linf=[0.0010140184322192658],
	initial_refinement_level=0)
	# Ensure that we do not have excessive memory allocations
	# (e.g., from type instabilities)
	@test_allocations(Trixi.rhs!, semi, sol, 1000)
	end

[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Trixi.jl/test/test_p4est_2d.jl

Lines 817 to 836 in e85eab6

	@trixi_testset "elixir_euler_mhd_coupled.jl" begin
	@test_trixi_include(joinpath(EXAMPLES_DIR, "elixir_euler_mhd_coupled.jl"),
	l2=[
	0.0009209778282789782, 0.0014756088960704886,
	2.6739154420876842e-5, 0.0, 0.002302285074638671,
	0.0, 0.0, 0.0, 0.0,
	0.00092795792971463, 0.001486604885621148,
	1.94903864271771e-7, 0.0023209501264139848
	],
	linf=[
	0.0016212187495835417, 0.0026481875873929084,
	0.00028267046396916696, 0.0, 0.004053956838104833,
	0.0, 0.0, 0.0, 0.0,
	0.0016010194777924536, 0.0026102809747779302,
	2.539799766164192e-6, 0.004014367354669757
	],
	tspan=(0.0, 0.02))
	# Ensure that we do not have excessive memory allocations
	# (e.g., from type instabilities)
	@test_broken (@allocated Trixi.rhs!(du_ode, u_ode, semi, t)) < 1000