Move indentation service to VS.Editor.Razor and export it.

- Removed indentation service extensions and made `GetDesiredIndentation` understand `ITextSnapshot`s and `ITextLineSnapshot`.
- Updated our test `StringTextSnapshot` implementation to have the required features our indentation tests require.
- Updated indentation service tests to use new API.

#1762

Author: N. Taylor Mullen

src/Microsoft.CodeAnalysis.Razor.Workspaces/DefaultRazorIndentationFactsServiceFactory.cs

@@ -3,28 +3,38 @@
 
 using System;
 using System.Collections.Generic;
+using System.ComponentModel.Composition;
 using Microsoft.AspNetCore.Razor.Language;
 using Microsoft.AspNetCore.Razor.Language.Legacy;
+using Microsoft.VisualStudio.Text;
+using Span = Microsoft.AspNetCore.Razor.Language.Legacy.Span;
 
-namespace Microsoft.CodeAnalysis.Razor
+namespace Microsoft.VisualStudio.Editor.Razor
 {
+    [System.Composition.Shared]
+    [Export(typeof(RazorIndentationFactsService))]
     internal class DefaultRazorIndentationFactsService : RazorIndentationFactsService
     {
-        public override int? GetDesiredIndentation(RazorSyntaxTree syntaxTree, int previousLineEndIndex, Func<int, string> getLineContent, int indentSize, int tabSize)
+        public override int? GetDesiredIndentation(
+            RazorSyntaxTree syntaxTree,
+            ITextSnapshot syntaxTreeSnapshot,
+            ITextSnapshotLine line,
+            int indentSize,
+            int tabSize)
         {
             if (syntaxTree == null)
             {
                 throw new ArgumentNullException(nameof(syntaxTree));
             }
 
-            if (previousLineEndIndex < 0)
+            if (syntaxTreeSnapshot == null)
             {
-                throw new ArgumentOutOfRangeException(nameof(previousLineEndIndex));
+                throw new ArgumentNullException(nameof(syntaxTreeSnapshot));
             }
 
-            if (getLineContent == null)
+            if (line == null)
             {
-                throw new ArgumentNullException(nameof(getLineContent));
+                throw new ArgumentNullException(nameof(line));
             }
 
             if (indentSize < 0)
@@ -37,6 +47,10 @@ internal class DefaultRazorIndentationFactsService : RazorIndentationFactsServic
                 throw new ArgumentOutOfRangeException(nameof(tabSize));
             }
 
+            var previousLine = line.Snapshot.GetLineFromLineNumber(line.LineNumber - 1);
+            var trackingPoint = previousLine.Snapshot.CreateTrackingPoint(previousLine.End, PointTrackingMode.Negative);
+            var previousLineEndIndex = trackingPoint.GetPosition(syntaxTreeSnapshot);
+
             var simulatedChange = new SourceChange(previousLineEndIndex, 0, string.Empty);
             var owningSpan = LocateOwner(syntaxTree.Root, simulatedChange);
             if (owningSpan.Kind == SpanKindInternal.Code)
@@ -80,8 +94,8 @@ currentSpan.Symbols[0] is CSharpSymbol symbol &&
                             // We can't rely on the syntax trees representation of the source document because partial parses may have mutated
                             // the underlying SyntaxTree text buffer. Because of this, if we want to provide accurate indentations we need to
                             // operate on the current line representation as indicated by the provider.
-                            var line = getLineContent(currentSpan.Start.LineIndex);
-                            desiredIndentation = GetIndentLevelOfLine(line, tabSize) + indentSize;
+                            var lineText = line.Snapshot.GetLineFromLineNumber(currentSpan.Start.LineIndex).GetText();
+                            desiredIndentation = GetIndentLevelOfLine(lineText, tabSize) + indentSize;
                         }
                     }
 

…s/DefaultRazorIndentationFactsService.cs …r/DefaultRazorIndentationFactsService.cssrc/Microsoft.CodeAnalysis.Razor.Workspaces/DefaultRazorIndentationFactsService.cs renamed to src/Microsoft.VisualStudio.Editor.Razor/DefaultRazorIndentationFactsService.cs src/Microsoft.CodeAnalysis.Razor.Workspaces/DefaultRazorIndentationFactsService.cs renamed to src/Microsoft.VisualStudio.Editor.Razor/DefaultRazorIndentationFactsService.cs

@@ -1,14 +1,14 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
 using Microsoft.AspNetCore.Razor.Language;
 using Microsoft.CodeAnalysis.Host;
+using Microsoft.VisualStudio.Text;
 
-namespace Microsoft.CodeAnalysis.Razor
+namespace Microsoft.VisualStudio.Editor.Razor
 {
     public abstract class RazorIndentationFactsService : ILanguageService
     {
-        public abstract int? GetDesiredIndentation(RazorSyntaxTree syntaxTree, int previousLineEnd, Func<int, string> lineProvider, int indentSize, int tabSize);
+        public abstract int? GetDesiredIndentation(RazorSyntaxTree syntaxTree, ITextSnapshot syntaxTreeSnapshot, ITextSnapshotLine line, int indentSize, int tabSize);
     }
 }

…rkspaces/RazorIndentationFactsService.cs …or.Razor/RazorIndentationFactsService.cssrc/Microsoft.CodeAnalysis.Razor.Workspaces/RazorIndentationFactsService.cs renamed to src/Microsoft.VisualStudio.Editor.Razor/RazorIndentationFactsService.cs src/Microsoft.CodeAnalysis.Razor.Workspaces/RazorIndentationFactsService.cs renamed to src/Microsoft.VisualStudio.Editor.Razor/RazorIndentationFactsService.cs

@@ -77,7 +77,20 @@ public ITextSnapshotLine GetLineFromPosition(int position)
             return matchingLine;
         }
 
-        public ITrackingPoint CreateTrackingPoint(int position, PointTrackingMode trackingMode) => throw new NotImplementedException();
+        public ITextSnapshotLine GetLineFromLineNumber(int lineNumber)
+        {
+            if (lineNumber < 0 || lineNumber >= _lines.Count)
+            {
+                throw new ArgumentOutOfRangeException(nameof(lineNumber));
+            }
+
+            return _lines[lineNumber];
+        }
+
+        public ITrackingPoint CreateTrackingPoint(int position, PointTrackingMode trackingMode)
+        {
+            return new SnapshotTrackingPoint(position);
+        }
 
         public ITrackingPoint CreateTrackingPoint(int position, PointTrackingMode trackingMode, TrackingFidelityMode trackingFidelity) => throw new NotImplementedException();
 
@@ -89,8 +102,6 @@ public ITextSnapshotLine GetLineFromPosition(int position)
 
         public ITrackingSpan CreateTrackingSpan(int start, int length, SpanTrackingMode trackingMode, TrackingFidelityMode trackingFidelity) => throw new NotImplementedException();
 
-        public ITextSnapshotLine GetLineFromLineNumber(int lineNumber) => throw new NotImplementedException();
-
         public int GetLineNumberFromPosition(int position) => throw new NotImplementedException();
 
         public string GetText(VisualStudio.Text.Span span) => throw new NotImplementedException();
@@ -133,6 +144,30 @@ private class TextChangeCollection : List<ITextChange>, INormalizedTextChangeCol
             }
         }
 
+        private class SnapshotTrackingPoint : ITrackingPoint
+        {
+            private readonly int _position;
+
+            public SnapshotTrackingPoint(int position)
+            {
+                _position = position;
+            }
+
+            public ITextBuffer TextBuffer => throw new NotImplementedException();
+
+            public PointTrackingMode TrackingMode => throw new NotImplementedException();
+
+            public TrackingFidelityMode TrackingFidelity => throw new NotImplementedException();
+
+            public char GetCharacter(ITextSnapshot snapshot) => throw new NotImplementedException();
+
+            public SnapshotPoint GetPoint(ITextSnapshot snapshot) => throw new NotImplementedException();
+
+            public int GetPosition(ITextSnapshot snapshot) => _position;
+
+            public int GetPosition(ITextVersion version) => throw new NotImplementedException();
+        }
+
         private class SnapshotLine : ITextSnapshotLine
         {
             private readonly string _contentWithLineBreak;
@@ -153,7 +188,9 @@ public SnapshotLine(string contentWithLineBreak, int start, ITextSnapshot owner)
                 }
 
                 Start = new SnapshotPoint(owner, start);
+                End = new SnapshotPoint(owner, start + _content.Length);
                 Snapshot = owner;
+                LineNumber = (owner as StringTextSnapshot)._lines.Count;
             }
 
             public ITextSnapshot Snapshot { get; }
@@ -172,14 +209,14 @@ public SnapshotLine(string contentWithLineBreak, int start, ITextSnapshot owner)
 
             public string GetTextIncludingLineBreak() => _contentWithLineBreak;
 
-            public int LineNumber => throw new NotImplementedException();
+            public int LineNumber { get; }
+
+            public SnapshotPoint End { get; }
 
             public SnapshotSpan Extent => throw new NotImplementedException();
 
             public SnapshotSpan ExtentIncludingLineBreak => throw new NotImplementedException();
 
-            public SnapshotPoint End => throw new NotImplementedException();
-
             public SnapshotPoint EndIncludingLineBreak => throw new NotImplementedException();
         }
     }