Fix - incorrect table markdown #2545

src/BenchmarkDotNet/Exporters/MarkdownExporter.cs

@@ -164,9 +164,9 @@ private void PrintTable(SummaryTable table, ILogger logger)
                 logger.WriteStatistic(ColumnsStartWithSeparator ? TableHeaderSeparator.TrimStart().TrimEnd() + "-" : "-");
 
                 logger.WriteLineStatistic(string.Join("",
-                    table.Columns.Where(c => c.NeedToShow).Select(column =>
+                    table.Columns.Where(c => c.NeedToShow).Select((column, index) =>
                         new string('-', column.Width - 1) + GetHeaderSeparatorIndicator(column.OriginalColumn.IsNumeric) +
-                        GetHeaderSeparatorColumnDivider(column.Index, table.ColumnCount))));
+                        GetHeaderSeparatorColumnDivider(index, table.Columns.Where(c => c.NeedToShow).Count()))));
             }
 
             int rowCounter = 0;

tests/BenchmarkDotNet.Tests/Exporters/MarkdownExporterVerifyTests.cs

@@ -14,6 +14,7 @@
 using JetBrains.Annotations;
 using VerifyXunit;
 using Xunit;
+using BenchmarkDotNet.Columns;
 
 namespace BenchmarkDotNet.Tests.Exporters
 {
@@ -40,9 +41,9 @@ public Task GroupExporterTest(Type benchmarkType)
 
             var logger = new AccumulationLogger();
             logger.WriteLine("=== " + benchmarkType.Name + " ===");
-
+            bool hasHideColumnsAttribute = benchmarkType.IsDefined(typeof(HideColumnsAttribute), false);
             var exporter = MarkdownExporter.Mock;
-            var summary = MockFactory.CreateSummary(benchmarkType);
+            var summary = hasHideColumnsAttribute ? MockFactory.CreateSummary(benchmarkType, new ColumnHidingByNameRule("StdDev")) : MockFactory.CreateSummary(benchmarkType);
             exporter.ExportToLog(summary, logger);
 
             var validator = BaselineValidator.FailOnError;
@@ -219,8 +220,8 @@ public class JobBaseline_MethodsParamsJobs
             [SimpleJob(id: "Job1", baseline: true), SimpleJob(id: "Job2")]
             public class MethodJobBaseline_MethodsJobs
             {
-                [Benchmark(Baseline = true)] public void Foo() {}
-                [Benchmark] public void Bar() {}
+                [Benchmark(Baseline = true)] public void Foo() { }
+                [Benchmark] public void Bar() { }
             }
 
             [RankColumn, LogicalGroupColumn, BaselineColumn]
@@ -229,25 +230,25 @@ public class MethodJobBaseline_MethodsJobsParams
             {
                 [Params(2, 10), UsedImplicitly] public int Param;
 
-                [Benchmark(Baseline = true)] public void Foo() {}
-                [Benchmark] public void Bar() {}
+                [Benchmark(Baseline = true)] public void Foo() { }
+                [Benchmark] public void Bar() { }
             }
 
             /* Invalid */
 
             [RankColumn, LogicalGroupColumn, BaselineColumn]
             public class Invalid_TwoMethodBaselines
             {
-                [Benchmark(Baseline = true)] public void Foo() {}
-                [Benchmark(Baseline = true)] public void Bar() {}
+                [Benchmark(Baseline = true)] public void Foo() { }
+                [Benchmark(Baseline = true)] public void Bar() { }
             }
 
             [RankColumn, LogicalGroupColumn, BaselineColumn]
             [SimpleJob(id: "Job1", baseline: true), SimpleJob(id: "Job2", baseline: true)]
             public class Invalid_TwoJobBaselines
             {
-                [Benchmark] public void Foo() {}
-                [Benchmark] public void Bar() {}
+                [Benchmark] public void Foo() { }
+                [Benchmark] public void Bar() { }
             }
 
             /* Escape Params */
@@ -260,6 +261,13 @@ public class Escape_ParamsAndArguments
                 [Benchmark] public void Foo(char charArg) {}
                 [Benchmark] public void Bar() {}
             }
+
+            /* Hide Column */
+            [HideColumns("StdDev")]
+            public class HideColumns_TableMarkDown
+            {
+                [Benchmark] public void Foo() { }
+            }
         }
     }
 }

tests/BenchmarkDotNet.Tests/Exporters/VerifiedFiles/MarkdownExporterVerifyTests.GroupExporterTest_HideColumns_TableMarkDown.verified.txt

@@ -0,0 +1,15 @@
+=== HideColumns_TableMarkDown ===
+
+BenchmarkDotNet v0.10.x-mock, Microsoft Windows NT 10.0.x.mock (Hyper-V)
+MockIntel Core i7-6700HQ CPU 2.60GHz (Max: 3.10GHz), 1 CPU, 8 logical and 4 physical cores
+Frequency: 2531248 Hz, Resolution: 395.062 ns, Timer: TSC
+  [Host]     : Clr 4.0.x.mock, 64mock RyuJIT-v4.6.x.mock CONFIGURATION
+  DefaultJob : extra output line
+
+StdDev=8.80 ns  
+
+ Method | Mean     | Error   | 
+------- |---------:|--------:|
+ Foo    | 114.5 ns | 5.88 ns | 
+
+Errors: 0

tests/BenchmarkDotNet.Tests/Mocks/MockFactory.cs

@@ -24,7 +24,7 @@ namespace BenchmarkDotNet.Tests.Mocks
 {
     public static class MockFactory
     {
-        public static Summary CreateSummary(Type benchmarkType)
+        public static Summary CreateSummary(Type benchmarkType, params IColumnHidingRule[] columHidingRules)
         {
             var runInfo = BenchmarkConverter.TypeToBenchmarks(benchmarkType);
             return new Summary(
@@ -36,7 +36,7 @@ public static Summary CreateSummary(Type benchmarkType)
                 TimeSpan.FromMinutes(1),
                 TestCultureInfo.Instance,
                 ImmutableArray<ValidationError>.Empty,
-                ImmutableArray<IColumnHidingRule>.Empty);
+                ImmutableArray.Create<IColumnHidingRule>(columHidingRules));
         }
 
         public static Summary CreateSummary(IConfig config) => new Summary(