Every test class says its area, and CI reports the suite's time by area (#1623)

The Area trait was on most test classes and nothing read it, so nothing
noticed the classes without one: 22 files when #1183 was filed, 37 now.
AreaTraitTest fails and names every test class with no [Trait("Area", …)],
and each of the 37 now carries the area its folder already uses.

The C# Test job's Ubuntu leg also writes a trx, and `dotnet run AreaTimes`
in Sources/Utils/Utils adds a table of time by area to the job summary.
The area is read from the test assembly, since a trx names a test's class
and not its traits; a class with none is counted as (none), so the table
adds up to the whole run.

Closes #1183.


Claude-Session: https://claude.ai/code/session_012sonx8iAspMiwRwokT1Ura

Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: Rafael-SOWNet

.github/workflows/CSharpTest.yml

@@ -40,7 +40,15 @@ jobs:
     - name: Test if not to send
       if: ${{ matrix.os != 'windows-latest' }}
       run: |
-        dotnet test "Sources/Tests/UnitTests" -c Release -l GitHubActions /p:CollectCoverage=true /p:CoverletOutputFormat=opencover
+        dotnet test "Sources/Tests/UnitTests" -c Release -l GitHubActions -l "trx;LogFileName=results.trx" --results-directory "Sources/Tests/UnitTests/TestResults" /p:CollectCoverage=true /p:CoverletOutputFormat=opencover
+
+    # Where the suite's time goes, by the Area trait every test class carries, written to the
+    # job's summary. One leg is enough to see the breakdown, and running the tool builds the
+    # library once more. https://github.com/asc-community/AngouriMath/issues/1183
+    - name: 'Time by area'
+      if: ${{ always() && matrix.os == 'ubuntu-latest' }}
+      run: dotnet run AreaTimes
+      working-directory: Sources/Utils/Utils
 
     - name: Test if to send
       if: ${{ matrix.os == 'windows-latest' }}

Sources/Tests/UnitTests/Algebra/EquationWithoutTheUnknownTest.cs

@@ -19,6 +19,7 @@ namespace AngouriMath.Tests.Algebra
     /// <c>x</c> satisfies it, and every <c>x</c> does whenever the two sides happen to be
     /// equal. https://github.com/asc-community/AngouriMath/issues/278
     /// </summary>
+    [Trait("Area", "Algebra")]
     public sealed class EquationWithoutTheUnknownTest
     {
         /// <summary>

Sources/Tests/UnitTests/Algebra/PythagoreanEquationRewriteTest.cs

@@ -26,6 +26,7 @@ namespace AngouriMath.Tests.Algebra
     /// <c>sin(x)^2 + sin(x) = 0</c> has always answered in arcsines. The mixed form simply
     /// never became one.
     /// </remarks>
+    [Trait("Area", "Algebra")]
     public sealed class PythagoreanEquationRewriteTest
     {
         /// <summary>

Sources/Tests/UnitTests/Calculus/BinomialIdentitiesTest.cs

@@ -21,6 +21,7 @@ namespace AngouriMath.Tests.Calculus
     /// second form), the parallel summation (Prob 8.9.19) and Vandermonde along the upper
     /// indices (Prob 8.9.18). <see href="https://github.com/asc-community/AngouriMath/issues/1409"/>
     /// </summary>
+    [Trait("Area", "Calculus")]
     public sealed class BinomialIdentitiesTest
     {
         /// <summary>The closed form against the sum written out, at small bounds and one past the expansion's hundred terms.</summary>

Sources/Tests/UnitTests/Calculus/BinomialSumTest.cs

@@ -17,6 +17,7 @@ namespace AngouriMath.Tests.Calculus
     /// https://github.com/asc-community/AngouriMath/issues/1212, question II.3: a binomial sum
     /// with a power or a trigonometric weight is the binomial theorem read backwards.
     /// </summary>
+    [Trait("Area", "Calculus")]
     public sealed class BinomialSumTest
     {
         private const string Binomial = "N! / (k! * (N - k)!)";

Sources/Tests/UnitTests/Calculus/BreakpointIntegrationTest.cs

@@ -18,6 +18,7 @@ namespace AngouriMath.Tests.Calculus
     /// through an antiderivative that holds the case or the step constant across them. Question
     /// I.2 of https://github.com/asc-community/AngouriMath/issues/1212, and the review of #1215.
     /// </summary>
+    [Trait("Area", "Calculus")]
     public sealed class BreakpointIntegrationTest
     {
         // ---- a piecewise: finitely many breakpoints ---------------------------------------------

Sources/Tests/UnitTests/Calculus/ConstantRateIntegrandTest.cs

@@ -23,6 +23,7 @@ namespace AngouriMath.Tests.Calculus
     /// gathering of two powers of one base turns <c>e^x * e^(-x)</c> into exactly this
     /// shape -- but the defect predates it and is reachable by writing the exponent out.
     /// </summary>
+    [Trait("Area", "Calculus")]
     public sealed class ConstantRateIntegrandTest
     {
         /// <summary>

Sources/Tests/UnitTests/Calculus/DivergentSeriesTest.cs

@@ -18,6 +18,7 @@ namespace AngouriMath.Tests.Calculus
     /// nth-term test, asked for on the review of
     /// https://github.com/asc-community/AngouriMath/pull/1218.
     /// </summary>
+    [Trait("Area", "Calculus")]
     public sealed class DivergentSeriesTest
     {
         [Theory]

Sources/Tests/UnitTests/Calculus/ExponentialSeriesTest.cs

@@ -17,6 +17,7 @@ namespace AngouriMath.Tests.Calculus
     /// https://github.com/asc-community/AngouriMath/issues/1212, question I.1: a summation to
     /// +oo of a polynomial times a power over a factorial of the index is a closed form in e.
     /// </summary>
+    [Trait("Area", "Calculus")]
     public sealed class ExponentialSeriesTest
     {
         private static void AgreesTo(string expected, Entity actual, int digits = 25)

Sources/Tests/UnitTests/Calculus/ExtremumTest.cs

@@ -17,6 +17,7 @@ namespace AngouriMath.Tests.Calculus
     /// <c>max(f(t), t in S)</c>, <c>min</c>, <c>argmax</c> and <c>argmin</c>: the extremum of an
     /// expression over a set, as binders. https://github.com/asc-community/AngouriMath/issues/1212
     /// </summary>
+    [Trait("Area", "Calculus")]
     public sealed class ExtremumTest
     {
         // The sheet's question I.6: the area of a projectile's flight is largest at pi/3.