Increase test coverage

Author: ufechner7

ext/VortexStepMethodControlPlotsExt.jl

@@ -584,6 +584,37 @@ function generate_polar_data(
     return polar_data, reynolds_number[1]
 end
 
+function _extract_literature_polar_data(raw_data, path)
+    table, header = if raw_data isa Tuple
+        # readdlm(...; header=true) returns (data, header)
+        raw_table, raw_header = raw_data
+        raw_table, lowercase.(strip.(string.(vec(raw_header))))
+    else
+        # Header is in first row when a single matrix is returned
+        raw_data[2:end, :], lowercase.(strip.(string.(raw_data[1, :])))
+    end
+
+    # Find column indices for alpha, CL, CD, CS (case-insensitive, allow common variants)
+    alpha_idx = findfirst(x -> occursin("alpha", x) || x == "aoa", header)
+    cl_idx = findfirst(x -> occursin("cl", x), header)
+    cd_idx = findfirst(x -> occursin("cd", x), header)
+    cs_idx = findfirst(x -> occursin("cs", x), header)
+
+    (isnothing(alpha_idx) || isnothing(cl_idx) || isnothing(cd_idx)) &&
+        throw(ArgumentError("Literature CSV must contain alpha/aoa, cl and cd columns: $path"))
+
+    # Fallback: if CS not found, fill with zeros
+    cs_col = cs_idx === nothing ? zeros(size(table, 1)) : table[:, cs_idx]
+
+    # Return as [alpha, CL, CD, CS]
+    return [
+        table[:, alpha_idx],
+        table[:, cl_idx],
+        table[:, cd_idx],
+        cs_col
+    ]
+end
+
 """
     plot_polars(solver_list, body_aero_list, label_list;
                 literature_path_list=String[],
@@ -658,22 +689,8 @@ function VortexStepMethod.plot_polars(
     # Load literature data if provided
     if !isempty(literature_path_list)
         for path in literature_path_list
-            data = readdlm(path, ',')
-            header = lowercase.(string.(data[1, :]))
-            # Find column indices for alpha, CL, CD, CS (case-insensitive, allow common variants)
-            alpha_idx = findfirst(x -> occursin("alpha", x), header)
-            cl_idx    = findfirst(x -> occursin("cl", x), header)
-            cd_idx    = findfirst(x -> occursin("cd", x), header)
-            cs_idx    = findfirst(x -> occursin("cs", x), header)
-            # Fallback: if CS not found, fill with zeros
-            cs_col = cs_idx === nothing ? zeros(size(data, 1)-1) : data[2:end, cs_idx]
-            # Push as [alpha, CL, CD, CS]
-            push!(polar_data_list, [
-                data[2:end, alpha_idx],
-                data[2:end, cl_idx],
-                data[2:end, cd_idx],
-                cs_col
-            ])
+            raw_data = readdlm(path, ',')
+            push!(polar_data_list, _extract_literature_polar_data(raw_data, path))
         end
     end
 

test/plotting/test_plotting.jl

@@ -227,6 +227,68 @@ end
         show_plot(fig_dpi)
         @test fig_dpi.get_dpi() == 130
         plt.close(fig_dpi)
+
+        ext = Base.get_extension(VortexStepMethod, :VortexStepMethodControlPlotsExt)
+        @test ext !== nothing
+
+        # Unit-test tuple parsing branch (e.g. readdlm(...; header=true) shape).
+        tuple_table = [0.0 0.10 0.010; 5.0 0.20 0.020]
+        tuple_header = [" AoA " "CL" "CD"]
+        tuple_pd = ext._extract_literature_polar_data((tuple_table, tuple_header), "tuple.csv")
+        @test tuple_pd[1] == tuple_table[:, 1]
+        @test tuple_pd[2] == tuple_table[:, 2]
+        @test tuple_pd[3] == tuple_table[:, 3]
+        @test tuple_pd[4] == zeros(size(tuple_table, 1))
+
+        # Unit-test matrix parsing branch (header in first row + explicit CS column).
+        matrix_data = Any[
+            "alpha" "cl" "cd" "cs";
+            0.0 0.11 0.011 0.001;
+            4.0 0.21 0.021 0.002
+        ]
+        matrix_pd = ext._extract_literature_polar_data(matrix_data, "matrix.csv")
+        @test Float64.(matrix_pd[1]) == [0.0, 4.0]
+        @test Float64.(matrix_pd[2]) == [0.11, 0.21]
+        @test Float64.(matrix_pd[3]) == [0.011, 0.021]
+        @test Float64.(matrix_pd[4]) == [0.001, 0.002]
+
+        # Missing required columns should throw a clear ArgumentError.
+        bad_data = Any[
+            "aoa" "cl" "cs";
+            0.0 0.1 0.0
+        ]
+        @test_throws ArgumentError ext._extract_literature_polar_data(bad_data, "bad.csv")
+
+        # Integration: literature CSV with AoA alias and no CS should still plot.
+        lit_no_cs_path = tempname() * "_lit_no_cs.csv"
+        open(lit_no_cs_path, "w") do io_no_cs
+            write(io_no_cs, "aoa,cl,cd\n0.0,0.10,0.010\n5.0,0.20,0.020\n")
+        end
+        fig_lit_no_cs = plot_polars(
+            Any[],
+            Any[],
+            ["Literature no CS"];
+            literature_path_list=[lit_no_cs_path],
+            is_save=false,
+            is_show=false
+        )
+        @test fig_lit_no_cs !== nothing
+        safe_rm(lit_no_cs_path)
+
+        # Integration: missing CD column should fail.
+        lit_bad_path = tempname() * "_lit_bad.csv"
+        open(lit_bad_path, "w") do io_bad
+            write(io_bad, "alpha,cl\n0.0,0.10\n5.0,0.20\n")
+        end
+        @test_throws ArgumentError plot_polars(
+            Any[],
+            Any[],
+            ["Literature bad"];
+            literature_path_list=[lit_bad_path],
+            is_save=false,
+            is_show=false
+        )
+        safe_rm(lit_bad_path)
     end
 end
 nothing