Don't use file GetOrCreateToken for change tracker (#2320)

Author: gabritto

internal/ast/ast.go

@@ -10940,6 +10940,8 @@ func (node *SourceFile) BindOnce(bind func()) {
 	})
 }
 
+// Gets a token from the file's token cache, or creates it if it does not already exist.
+// This function should NOT be used for creating synthetic tokens that are not in the file in the first place.
 func (node *SourceFile) GetOrCreateToken(
 	kind Kind,
 	pos int,

internal/ls/change/tracker.go

@@ -178,7 +178,9 @@ func (t *Tracker) InsertNodeBefore(sourceFile *ast.SourceFile, before *ast.Node,
 // InsertModifierBefore inserts a modifier token (like 'type') before a node with a trailing space.
 func (t *Tracker) InsertModifierBefore(sourceFile *ast.SourceFile, modifier ast.Kind, before *ast.Node) {
 	pos := astnav.GetStartOfNode(before, sourceFile, false)
-	token := sourceFile.GetOrCreateToken(modifier, pos, pos, before.Parent, ast.TokenFlagsNone)
+	token := t.NewToken(modifier)
+	token.Loc = core.NewTextRange(pos, pos)
+	token.Parent = before.Parent
 	t.InsertNodeAt(sourceFile, core.TextPos(pos), token, NodeOptions{Suffix: " "})
 }
 
@@ -260,9 +262,12 @@ func (t *Tracker) endPosForInsertNodeAfter(sourceFile *ast.SourceFile, after *as
 		// check if previous statement ends with semicolon
 		// if not - insert semicolon to preserve the code from changing the meaning due to ASI
 		endPos := t.converters.PositionToLineAndCharacter(sourceFile, core.TextPos(after.End()))
+		semicolon := t.NewToken(ast.KindSemicolonToken)
+		semicolon.Loc = core.NewTextRange(after.End(), after.End())
+		semicolon.Parent = after.Parent
 		t.ReplaceRange(sourceFile,
 			lsproto.Range{Start: endPos, End: endPos},
-			sourceFile.GetOrCreateToken(ast.KindSemicolonToken, after.End(), after.End(), after.Parent, ast.TokenFlagsNone),
+			semicolon,
 			NodeOptions{},
 		)
 	}
@@ -347,7 +352,10 @@ func (t *Tracker) InsertNodeInListAfter(sourceFile *ast.SourceFile, after *ast.N
 
 	// insert separator immediately following the 'after' node to preserve comments in trailing trivia
 	// !!! formatcontext
-	t.ReplaceRange(sourceFile, lsproto.Range{Start: end, End: end}, sourceFile.GetOrCreateToken(separator, after.End(), after.End()+len(separatorString), after.Parent, ast.TokenFlagsNone), NodeOptions{})
+	separatorToken := t.NewToken(separator)
+	separatorToken.Loc = core.NewTextRange(after.End(), after.End()+len(separatorString))
+	separatorToken.Parent = after.Parent
+	t.ReplaceRange(sourceFile, lsproto.Range{Start: end, End: end}, separatorToken, NodeOptions{})
 	// use the same indentation as 'after' item
 	indentation := format.FindFirstNonWhitespaceColumn(afterStartLinePosition, afterStart, sourceFile, t.formatSettings)
 	// insert element before the line break on the line that contains 'after' element