Track formatter ranges through iterative corrections

Engine/Formatter.cs

@@ -54,6 +54,7 @@ public static string Format<TCmdlet>(
             ScriptBlockAst scriptAst = null;
             Token[] scriptTokens = null;
             bool skipParsing = false;
+            bool isRangeSpecified = range != null;
             foreach (var rule in ruleOrder)
             {
                 if (!settings.RuleArguments.ContainsKey(rule))
@@ -68,6 +69,10 @@ public static string Format<TCmdlet>(
                 text = ScriptAnalyzer.Instance.Fix(text, range, skipParsing, out Range updatedRange, out bool fixesWereApplied, ref scriptAst, ref scriptTokens, skipVariableAnalysis: true);
                 skipParsing = !fixesWereApplied;
                 range = updatedRange;
+                if (isRangeSpecified && range == null)
+                {
+                    break;
+                }
             }
 
             return text.ToString();

Engine/ScriptAnalyzer.cs

@@ -1556,7 +1556,6 @@ public EditableText Fix(EditableText text, Range range, bool skipParsing, out Ra
             }
 
             range = isRangeNull ? null : SnapToEdges(text, range);
-            var previousLineCount = text.LineCount;
             var previousUnusedCorrections = 0;
             do
             {
@@ -1578,7 +1577,7 @@ public EditableText Fix(EditableText text, Range range, bool skipParsing, out Ra
 
                 this.outputWriter.WriteVerbose($"Found {corrections.Count} violations.");
                 int unusedCorrections;
-                Fix(text, corrections, out unusedCorrections);
+                Fix(text, corrections, out unusedCorrections, ref range);
                 var numberOfFixedViolatons = corrections.Count - unusedCorrections;
                 fixesWereApplied = numberOfFixedViolatons > 0;
                 this.outputWriter.WriteVerbose($"Fixed {numberOfFixedViolatons} violations.");
@@ -1595,17 +1594,7 @@ public EditableText Fix(EditableText text, Range range, bool skipParsing, out Ra
                 }
 
                 previousUnusedCorrections = unusedCorrections;
-                var lineCount = text.LineCount;
-                if (!isRangeNull && lineCount != previousLineCount)
-                {
-                    range = new Range(
-                        range.Start,
-                        range.End.Shift(lineCount - previousLineCount, 0));
-                    range = SnapToEdges(text, range);
-                }
-
-                previousLineCount = lineCount;
-            } while (previousUnusedCorrections > 0);
+            } while (previousUnusedCorrections > 0 && (isRangeNull || range != null));
 
             updatedRange = range;
             return text;
@@ -1728,14 +1717,47 @@ private static IEnumerable<CorrectionExtent> GetCorrectionExtentsForFix(
         private static EditableText Fix(
             EditableText text,
             List<CorrectionExtent> correctionExtents,
-            out int unusedCorrections)
+            out int unusedCorrections,
+            ref Range range)
         {
             var correctionsToUse = GetCorrectionExtentsForFix(correctionExtents);
             var count = 0;
             foreach (var correction in correctionsToUse)
             {
                 count++;
                 text.ApplyEdit(correction);
+                if (range != null)
+                {
+                    var lineDelta = correction.Lines.Length - 1
+                        - (correction.EndLineNumber - correction.StartLineNumber);
+                    var columnDelta = 0;
+                    if (correction.EndLineNumber == range.End.Line)
+                    {
+                        var replacementEndColumn = correction.Lines.Length == 0
+                            ? correction.StartColumnNumber
+                            : correction.Lines.Last().TrimEnd('\r').Length
+                                + (correction.Lines.Length == 1 ? correction.StartColumnNumber : 1);
+                        columnDelta = replacementEndColumn - correction.EndColumnNumber;
+                    }
+
+                    var endLine = range.End.Line + lineDelta;
+                    if (correction.Lines.Length == 0 && endLine < range.Start.Line)
+                    {
+                        range = null;
+                    }
+                    else if (correction.Lines.Length == 0
+                        && lineDelta < 0
+                        && correction.EndLineNumber == range.End.Line)
+                    {
+                        range = new Range(
+                            range.Start,
+                            new Position(endLine, text.Lines[endLine - 1].Length + 1));
+                    }
+                    else
+                    {
+                        range = new Range(range.Start, range.End.Shift(lineDelta, columnDelta));
+                    }
+                }
             }
 
             unusedCorrections = correctionExtents.Count - count;

Tests/Engine/InvokeFormatter.tests.ps1

@@ -81,6 +81,101 @@ function foo {
 
             Invoke-Formatter -ScriptDefinition $def -Range @(3, 1, 4, 1) | Should -Be $expected
         }
+
+        It "Should track the range when an edit deletes its last line" {
+            $text = New-Object -TypeName "Microsoft.Windows.PowerShell.ScriptAnalyzer.EditableText" -ArgumentList "first`n`nlast"
+            $correctionType = "Microsoft.Windows.PowerShell.ScriptAnalyzer.Generic.CorrectionExtent" -as [type]
+            $correction = [Activator]::CreateInstance(
+                $correctionType,
+                [object[]]@(2, 2, 1, 1, [string[]]@(), $null, $null))
+            $correctionsType = [System.Collections.Generic.List``1].MakeGenericType($correctionType)
+            $corrections = [Activator]::CreateInstance($correctionsType)
+            $corrections.Add($correction)
+            $range = New-Object -TypeName "Microsoft.Windows.PowerShell.ScriptAnalyzer.Range" -ArgumentList 1, 1, 2, 1
+            $arguments = [object[]]@(
+                $text.PSObject.BaseObject,
+                $corrections.PSObject.BaseObject,
+                0,
+                $range.PSObject.BaseObject)
+            $fixMethod = ("Microsoft.Windows.PowerShell.ScriptAnalyzer.ScriptAnalyzer" -as [type]).GetMethod(
+                'Fix',
+                [Reflection.BindingFlags]'NonPublic, Static')
+
+            $fixMethod.Invoke($null, $arguments) | Out-Null
+
+            $text.ToString() | Should -Be "first`nlast"
+            $arguments[3].End.Line | Should -Be 1
+            $arguments[3].End.Column | Should -Be 6
+        }
+
+        It "Should exhaust the range when an edit deletes all selected lines" {
+            $text = New-Object -TypeName "Microsoft.Windows.PowerShell.ScriptAnalyzer.EditableText" -ArgumentList "first`nlast"
+            $correctionType = "Microsoft.Windows.PowerShell.ScriptAnalyzer.Generic.CorrectionExtent" -as [type]
+            $correction = [Activator]::CreateInstance(
+                $correctionType,
+                [object[]]@(2, 2, 1, 5, [string[]]@(), $null, $null))
+            $correctionsType = [System.Collections.Generic.List``1].MakeGenericType($correctionType)
+            $corrections = [Activator]::CreateInstance($correctionsType)
+            $corrections.Add($correction)
+            $range = New-Object -TypeName "Microsoft.Windows.PowerShell.ScriptAnalyzer.Range" -ArgumentList 2, 1, 2, 5
+            $arguments = [object[]]@(
+                $text.PSObject.BaseObject,
+                $corrections.PSObject.BaseObject,
+                0,
+                $range.PSObject.BaseObject)
+            $fixMethod = ("Microsoft.Windows.PowerShell.ScriptAnalyzer.ScriptAnalyzer" -as [type]).GetMethod(
+                'Fix',
+                [Reflection.BindingFlags]'NonPublic, Static')
+
+            $fixMethod.Invoke($null, $arguments) | Out-Null
+            $text.ToString() | Should -Be "first"
+            $arguments[3] | Should -BeNullOrEmpty
+        }
+
+        It "Should apply all corrections when earlier fixes expand the selected line" {
+            $def = "if(`$a){'x'}`nif(`$b){'y'}"
+            $expected = "if(`$a){'x'}`nif (`$b) { 'y' }"
+
+            Invoke-Formatter -ScriptDefinition $def -Range @(2, 1, 2, 12) | Should -Be $expected
+        }
+
+        It "Should track the selected lines when fixes <Name>" -TestCases @(
+            @{
+                Name = 'expand the last line'
+                Selected = "if(`$b){'y'}"
+                Expected = "if (`$b) { 'y' }"
+            }
+            @{
+                Name = 'shorten the last line'
+                Selected = "if  (`$b)  {  'y'  }"
+                Expected = "if (`$b) { 'y' }"
+            }
+            @{
+                Name = 'expand multiple lines'
+                Selected = "if(`$b){'y'}`nif(`$c){'z'}"
+                Expected = "if (`$b) { 'y' }`nif (`$c) { 'z' }"
+            }
+            @{
+                Name = 'remove a line'
+                Selected = "if(`$b)`n{`n'y'`n}"
+                Expected = "if (`$b) {`n    'y'`n}"
+            }
+            @{
+                Name = 'add a line'
+                Selected = "if(`$b) {`n'y'`n}"
+                Expected = "if (`$b)`n{`n    'y'`n}"
+                Settings = 'CodeFormattingAllman'
+            }
+        ) {
+            param($Selected, $Expected, $Settings = 'CodeFormatting')
+
+            $def = "if(`$a){'x'}`n$Selected`nif(`$d){'w'}"
+            $lines = $Selected -split "`n"
+            $range = @(2, 1, (1 + $lines.Count), (1 + $lines[-1].Length))
+
+            Invoke-Formatter -ScriptDefinition $def -Range $range -Settings $Settings |
+                Should -Be "if(`$a){'x'}`n$Expected`nif(`$d){'w'}"
+        }
     }
 
     Context "When no settings are given" {