Function calculateFinalCursorPosition

core/nextEdit/diff/diff.ts:207–239

(
  currCursorPos: Position,
  editableRegionStartLine: number,
  oldEditRangeSlice: string,
  newEditRangeSlice: string,
)

}

export function calculateFinalCursorPosition(
  currCursorPos: Position,
  editableRegionStartLine: number,
  oldEditRangeSlice: string,
  newEditRangeSlice: string,
) {
  if (newEditRangeSlice === "") {
    return currCursorPos;
  }
  // How far away is the current line from the start of the editable region?
  const lineOffsetAtCursorPos = currCursorPos.line - editableRegionStartLine;

  // How long is the line at the current cursor position?
  const lineContentAtCursorPos =
    newEditRangeSlice.split("\n")[lineOffsetAtCursorPos];

  const diffLines = myersDiff(oldEditRangeSlice, newEditRangeSlice);

  const offset = getOffsetPositionAtLastNewLine(
    diffLines,
    lineContentAtCursorPos,
    lineOffsetAtCursorPos,
  );

  // Calculate the actual line number in the editor by adding the startPos offset
  // to the line number from the diff calculation.
  const finalCursorPos: Position = {
    line: editableRegionStartLine + offset.line,
    character: offset.character,
  };

  return finalCursorPos;
}

/**
 * Applies a completion to file content by replacing lines starting from a specific line number