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- Rename charDelta to lastLineCharDelta
- Return non-optional from updateDocumentTokens closure

Author: fwcd

Sources/SourceKitLSP/DocumentManager.swift

@@ -128,7 +128,7 @@ public final class DocumentManager {
     newVersion: Int,
     edits: [TextDocumentContentChangeEvent],
     willEditDocument: ((_ before: DocumentSnapshot, TextDocumentContentChangeEvent) -> Void)? = nil,
-    updateDocumentTokens: ((_ after: DocumentSnapshot) -> DocumentTokens?)? = nil
+    updateDocumentTokens: ((_ after: DocumentSnapshot) -> DocumentTokens)? = nil
   ) throws -> DocumentSnapshot {
     return try queue.sync {
       guard let document = documents[uri] else {
@@ -155,7 +155,7 @@ public final class DocumentManager {
           let upperUtf16IndexAfterEdit = (
             newLines.count == 1 ? range.lowerBound.utf16index : 0
           ) + newLines.last!.utf16.count
-          let charDelta = upperUtf16IndexAfterEdit - range.upperBound.utf16index
+          let lastLineCharDelta = upperUtf16IndexAfterEdit - range.upperBound.utf16index
           let lineDelta = newLines.count - replacedLineCount // may be negative
 
           document.latestTokens.withMutableTokensOfEachKind { tokens in
@@ -169,7 +169,7 @@ public final class DocumentManager {
                 var token = $0
                 if token.start.line == range.upperBound.line
                   && token.start.utf16index >= range.upperBound.utf16index {
-                  token.move(lineDelta: lineDelta, utf16indexDelta: charDelta)
+                  token.move(lineDelta: lineDelta, utf16indexDelta: lastLineCharDelta)
                 } else if token.start.line > range.upperBound.line {
                   token.move(lineDelta: lineDelta)
                 }
@@ -182,8 +182,8 @@ public final class DocumentManager {
           document.latestTokens = DocumentTokens()
         }
 
-        if let f = updateDocumentTokens, let tokens = f(document.latestSnapshot) {
-          document.latestTokens = tokens
+        if let f = updateDocumentTokens {
+          document.latestTokens = f(document.latestSnapshot)
         }
       }
 
@@ -245,7 +245,7 @@ extension DocumentManager {
   func edit(
     _ note: DidChangeTextDocumentNotification,
     willEditDocument: ((_ before: DocumentSnapshot, TextDocumentContentChangeEvent) -> Void)? = nil,
-    updateDocumentTokens: ((_ after: DocumentSnapshot) -> DocumentTokens?)? = nil
+    updateDocumentTokens: ((_ after: DocumentSnapshot) -> DocumentTokens)? = nil
   ) -> DocumentSnapshot? {
     return orLog("failed to edit document", level: .error) {
       try edit(