Add range formatting capability

Author: Kapil Borle

Engine/Commands/InvokeFormatterCommand.cs

@@ -37,6 +37,18 @@ public class InvokeFormatterCommand : PSCmdlet, IOutputWriter
         [ValidateNotNull]
         public object Settings { get; set; }
 
+        // [Parameter(Mandatory = false)]
+        // public Range range { get; set; }
+
+        [Parameter(Mandatory = false)]
+        public int StartLineNumber { get; set; } = -1;
+        [Parameter(Mandatory = false)]
+        public int StartColumnNumber { get; private set; } = -1;
+        [Parameter(Mandatory = false)]
+        public int EndLineNumber { get; private set; } = -1;
+        [Parameter(Mandatory = false)]
+        public int EndColumnNumber { get; private set; } = -1;
+
 #if DEBUG
         /// <summary>
         /// Attaches to an instance of a .Net debugger
@@ -47,6 +59,7 @@ public SwitchParameter AttachAndDebug
             get { return attachAndDebug; }
             set { attachAndDebug = value; }
         }
+
         private bool attachAndDebug = false;
 #endif
 
@@ -85,7 +98,12 @@ protected override void BeginProcessing()
 
         protected override void ProcessRecord()
         {
-            var text = Formatter.Format(ScriptDefinition, inputSettings, this);
+            // todo add range parameter
+            // todo add tests to check range formatting
+            var range = StartLineNumber == -1 ?
+                null :
+                new Range(StartLineNumber, StartColumnNumber, EndLineNumber, EndColumnNumber);
+            var text = Formatter.Format(ScriptDefinition, inputSettings, range, this);
             this.WriteObject(text);
         }
 

Engine/Formatter.cs

@@ -14,6 +14,7 @@ public class Formatter
         public static string Format<TCmdlet>(
             string scriptDefinition,
             Settings settings,
+            Range range,
             TCmdlet cmdlet) where TCmdlet : PSCmdlet, IOutputWriter
         {
             Helper.Instance = new Helper(cmdlet.SessionState.InvokeCommand, cmdlet);
@@ -40,7 +41,7 @@ public static string Format<TCmdlet>(
                 var currentSettings = GetCurrentSettings(settings, rule);
                 ScriptAnalyzer.Instance.UpdateSettings(currentSettings);
                 ScriptAnalyzer.Instance.Initialize(cmdlet, null, null, null, null, true, false);
-                text = ScriptAnalyzer.Instance.Fix(text);
+                text = ScriptAnalyzer.Instance.Fix(text, range);
             }
 
             return text.ToString();

Engine/ScriptAnalyzer.cs

@@ -1539,21 +1539,25 @@ public string Fix(string scriptDefinition)
                 throw new ArgumentNullException(nameof(scriptDefinition));
             }
 
-            return Fix(new EditableText(scriptDefinition)).ToString();
+            return Fix(new EditableText(scriptDefinition), null).ToString();
         }
 
         /// <summary>
         /// Fix the violations in the given script text.
         /// </summary>
         /// <param name="text">An object of type `EditableText` that encapsulates the script text to be fixed.</param>
         /// <returns>The same instance of `EditableText` that was passed to the method, but the instance encapsulates the fixed script text. This helps in chaining the Fix method.</returns>
-        public EditableText Fix(EditableText text)
+        public EditableText Fix(EditableText text, Range range)
         {
             if (text == null)
             {
                 throw new ArgumentNullException(nameof(text));
             }
 
+            // todo validate range
+            var isRangeNull = range == null;
+            range = isRangeNull ? null : SnapToEdges(text, range);
+            var previousLineCount = text.Lines.Length;
             var previousUnusedCorrections = 0;
             do
             {
@@ -1562,6 +1566,7 @@ public EditableText Fix(EditableText text)
                     .Select(r => r.SuggestedCorrections)
                     .Where(sc => sc != null && sc.Any())
                     .Select(sc => sc.First())
+                    .Where(sc => isRangeNull || (sc.Start >= range.Start && sc.End <= range.End))
                     .ToList();
 
                 int unusedCorrections;
@@ -1579,11 +1584,34 @@ public EditableText Fix(EditableText text)
                 }
 
                 previousUnusedCorrections = unusedCorrections;
+
+                // todo add a TextLines.NumLines property because accessing TextLines.Lines is expensive
+                var lineCount = text.Lines.Length;
+                if (!isRangeNull && lineCount != previousLineCount)
+                {
+                    range = new Range(
+                        range.Start,
+                        range.End.Shift(lineCount - previousLineCount, 0));
+                    range = SnapToEdges(text, range);
+                }
+
+                previousLineCount = lineCount;
             } while (previousUnusedCorrections > 0);
 
             return text;
         }
 
+        private static Range SnapToEdges(EditableText text, Range range)
+        {
+            // todo add TextLines.Validate(range) and TextLines.Validate(position)
+            // todo TextLines.Lines should return IList instead of array because TextLines.Lines is expensive
+            return new Range(
+                range.Start.Line,
+                Math.Min(range.Start.Column, 1),
+                range.End.Line,
+                Math.Max(range.End.Column, text.Lines[range.End.Line - 1].Length));
+        }
+
         private static IEnumerable<CorrectionExtent> GetCorrectionExtentsForFix(
             IEnumerable<CorrectionExtent> correctionExtents)
         {