Add configuration.Output.ShowStartMarkers support (fixes pester#2583).

Allow displaying an indication when each test starts:
[|] Test name...

src/csharp/Pester/OutputConfiguration.cs

@@ -24,6 +24,7 @@ public class OutputConfiguration : ConfigurationSection
     {
         private StringOption _verbosity;
         private StringOption _stackTraceVerbosity;
+        private BoolOption _showStartMarkers;
         private StringOption _ciFormat;
         private StringOption _ciLogLevel;
         private StringOption _renderMode;
@@ -40,6 +41,7 @@ public OutputConfiguration(IDictionary configuration) : this()
             {
                 configuration.AssignObjectIfNotNull<string>(nameof(Verbosity), v => Verbosity = v);
                 configuration.AssignObjectIfNotNull<string>(nameof(StackTraceVerbosity), v => StackTraceVerbosity = v);
+                configuration.AssignValueIfNotNull<bool>(nameof(ShowStartMarkers), v => ShowStartMarkers = v);
                 configuration.AssignObjectIfNotNull<string>(nameof(CIFormat), v => CIFormat = v);
                 configuration.AssignObjectIfNotNull<string>(nameof(CILogLevel), v => CILogLevel = v);
                 configuration.AssignObjectIfNotNull<string>(nameof(RenderMode), v => RenderMode = v);
@@ -50,6 +52,7 @@ public OutputConfiguration() : base("Options to customize the console output gen
         {
             Verbosity = new StringOption("The verbosity of output, options are None, Normal, Detailed and Diagnostic.", "Normal");
             StackTraceVerbosity = new StringOption("The verbosity of stacktrace output, options are None, FirstLine, Filtered and Full.", "Filtered");
+            ShowStartMarkers = new BoolOption("Write an indication when each test starts.", false);
             CIFormat = new StringOption("The CI format of error output in build logs, options are None, Auto, AzureDevops and GithubActions.", "Auto");
             CILogLevel = new StringOption("The CI log level in build logs, options are Error and Warning.", "Error");
             RenderMode = new StringOption("The mode used to render console output, options are Auto, Ansi, ConsoleColor and Plaintext.", "Auto");
@@ -87,6 +90,22 @@ public StringOption StackTraceVerbosity
             }
         }
 
+        public BoolOption ShowStartMarkers
+        {
+            get { return _showStartMarkers; }
+            set
+            {
+                if (_showStartMarkers == null)
+                {
+                    _showStartMarkers = value;
+                }
+                else
+                {
+                    _showStartMarkers = new BoolOption(_showStartMarkers, value.Value);
+                }
+            }
+        }
+
         public StringOption CIFormat
         {
             get { return _ciFormat; }

src/en-US/about_PesterConfiguration.help.txt

@@ -195,6 +195,10 @@ SECTIONS AND OPTIONS
         Type: string
         Default value: 'Filtered'
 
+        ShowStartMarkers: Write an indication when each test starts.
+        Type: bool
+        Default value: $false
+
         CIFormat: The CI format of error output in build logs, options are None, Auto, AzureDevops and GithubActions.
         Type: string
         Default value: 'Auto'

src/functions/Output.ps1

@@ -607,10 +607,20 @@ function Get-WriteScreenPlugin ($Verbosity) {
     if ($PesterPreference.Output.Verbosity.Value -in 'Detailed', 'Diagnostic') {
         $p.EachTestSetupStart = {
             param ($Context)
+
+            # we are currently in scope of describe so $Test is hardtyped and conflicts
+            $_test = $Context.Test
+
             # we postponed writing the Describe / Context to grab the Expanded name, because that is done
             # during execution to get all the variables in scope, if we are the first test then write it
-            if ($Context.Test.First) {
-                Write-BlockToScreen $Context.Test.Block
+            if ($_test.First) {
+                Write-BlockToScreen $_test.Block
+            }
+
+            if ($PesterPreference.Output.ShowStartMarkers.Value) {
+                $level = $_test.Path.Count
+                $margin = $ReportStrings.Margin * ($level)
+                Write-PesterHostMessage -ForegroundColor $ReportTheme.Information "$margin[|] $($_test.ExpandedName)..."
             }
         }
     }

tst/Pester.RSpec.Configuration.ts.ps1

@@ -74,6 +74,10 @@ i -PassThru:$PassThru {
             [PesterConfiguration]::Default.Output.StackTraceVerbosity.Value | Verify-Equal Filtered
         }
 
+        t "Output.ShowStartMarkers is `$false" {
+            [PesterConfiguration]::Default.Output.ShowStartMarkers.Value | Verify-False
+        }
+
         t "Output.CIFormat is Auto" {
             [PesterConfiguration]::Default.Output.CIFormat.Value | Verify-Equal Auto
         }

tst/Pester.RSpec.Output.ts.ps1

@@ -141,6 +141,49 @@ i -PassThru:$PassThru {
             @($describeFailing).Count | Verify-Equal 1
             @($contextFailing).Count | Verify-Equal 1
         }
+
+        t 'All start markers are output when ShowStartMarkers is enabled' {
+            $sb = {
+                $PesterPreference = [PesterConfiguration]::Default
+                $PesterPreference.Output.Verbosity = 'Detailed'
+                $PesterPreference.Output.ShowStartMarkers = $true
+                $PesterPreference.Output.CIFormat = 'None'
+                $PesterPreference.Output.RenderMode = 'ConsoleColor'
+
+                $container = New-PesterContainer -ScriptBlock {
+                    Describe 'd1' {
+                        Context 'c1' {
+                            It 'i1' {
+                                1 | Should -Be 1
+                            }
+
+                            It 'i2' {
+                                1 | Should -Be 1
+                            }
+                        }
+
+                        Context 'c2' {
+                            It 'i3' {
+                                1 | Should -Be 1
+                            }
+                        }
+                    }
+                }
+                Invoke-Pester -Container $container
+            }
+
+            $output = Invoke-InNewProcess $sb
+            # only print the relevant part of output
+            $null, $run = $output -join "`n" -split 'Running tests.'
+            $run | Write-Host
+
+            $i1Start = $output | Select-String -Pattern '\[\|\] i1\.\.\.$'
+            @($i1Start).Count | Verify-Equal 1
+            $i2Start = $output | Select-String -Pattern '\[\|\] i2\.\.\.$'
+            @($i2Start).Count | Verify-Equal 1
+            $i3Start = $output | Select-String -Pattern '\[\|\] i3\.\.\.$'
+            @($i3Start).Count | Verify-Equal 1
+        }
     }
 
     b 'Output for data-driven blocks' {