Fix formatting regression in 1.18.0 whereby single-line pipeline reduces indentation level incorrectly (#1191)

* Fix issue whereby single-line pipeline reduces indentation level incorrectly (problem only showed up when there was already existing indentation due to ClipNegative

* Apply suggestions from code review

Co-Authored-By: bergmeister <c.bergmeister@gmail.com>

* Fix tests by replacing break with continue (forgot I was inside for loop and not switch statement), simple mistake

Author: bergmeister

Rules/UseConsistentIndentation.cs

@@ -220,16 +220,25 @@ public override IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string file
                 // Check if the current token matches the end of a PipelineAst
                 var matchingPipeLineAstEnd = pipelineAsts.FirstOrDefault(pipelineAst =>
                         PositionIsEqual(pipelineAst.Extent.EndScriptPosition, token.Extent.EndScriptPosition)) as PipelineAst;
-                if (matchingPipeLineAstEnd != null)
+
+                if (matchingPipeLineAstEnd == null)
                 {
-                    if (pipelineIndentationStyle == PipelineIndentationStyle.IncreaseIndentationForFirstPipeline)
-                    {
-                        indentationLevel = ClipNegative(indentationLevel - 1);
-                    }
-                    else if (pipelineIndentationStyle == PipelineIndentationStyle.IncreaseIndentationAfterEveryPipeline)
-                    {
-                        indentationLevel = ClipNegative(indentationLevel - (matchingPipeLineAstEnd.PipelineElements.Count - 1));
-                    }
+                    continue;
+                }
+
+                bool pipelineSpansOnlyOneLine = matchingPipeLineAstEnd.Extent.StartLineNumber == matchingPipeLineAstEnd.Extent.EndLineNumber;
+                if (pipelineSpansOnlyOneLine)
+                {
+                    continue;
+                }
+
+                if (pipelineIndentationStyle == PipelineIndentationStyle.IncreaseIndentationForFirstPipeline)
+                {
+                    indentationLevel = ClipNegative(indentationLevel - 1);
+                }
+                else if (pipelineIndentationStyle == PipelineIndentationStyle.IncreaseIndentationAfterEveryPipeline)
+                {
+                    indentationLevel = ClipNegative(indentationLevel - (matchingPipeLineAstEnd.PipelineElements.Count - 1));
                 }
             }
 

Tests/Rules/UseConsistentIndentation.tests.ps1

@@ -174,6 +174,23 @@ baz
             Test-CorrectionExtentFromContent @params
         }
 
+        It "Should preserve script when using PipelineIndentation <PipelineIndentation>" -TestCases @(
+                @{ PipelineIndentation = 'IncreaseIndentationForFirstPipeline' }
+                @{ PipelineIndentation = 'IncreaseIndentationAfterEveryPipeline' }
+                @{ PipelineIndentation = 'NoIndentation' }
+                ) {
+            param ($PipelineIndentation)
+            $idempotentScriptDefinition = @'
+function hello {
+    if ($true) {
+        "hello" | Out-Host
+    }
+}
+'@
+            $settings.Rules.PSUseConsistentIndentation.PipelineIndentation = $PipelineIndentation
+            Invoke-Formatter -ScriptDefinition $idempotentScriptDefinition -Settings $settings | Should -Be $idempotentScriptDefinition
+        }
+
         It "Should indent pipelines correctly using NoIndentation option" {
             $def = @'
 foo |