@krassowski/jupyterlab_go_to_definition/src/testutils.ts

Jump to definition of a variable or function in JupyterLab

import { CodeJumper } from './jumpers/jumper';
import { CodeEditor } from '@jupyterlab/codeeditor';
import { IJump, IJumpPosition } from './jump';

export function matchToken(
  tokens: ReadonlyArray<CodeEditor.IToken>,
  tokenName: string,
  tokenOccurrence = 1,
  tokenType = 'variable'
): CodeEditor.IToken {
  let matchedTokens = tokens.filter(
    token => token.value === tokenName && token.type === tokenType
  );
  return matchedTokens[tokenOccurrence - 1];
}

// TODO: refactor into a factory which accepts language and cwd as options
export class Jumper extends CodeJumper {
  cwd = '';
  language: string = 'python';
  editor: CodeEditor.IEditor;

  constructor(editor: CodeEditor.IEditor) {
    super();
    this.editor = editor;
  }

  get editors() {
    return [this.editor];
  }

  jump_to_definition(jump: IJump) {
    let { token } = this._findLastDefinition(jump.token, 0);

    // nothing found
    if (!token) {
      return;
    }

    let position = this.editor.getPositionAt(token.offset);
    this.editor.setSelection({ start: position, end: position });
  }

  jump(position: IJumpPosition): void {
    // nothing here yet
  }
  getOffset(position: CodeEditor.IPosition, cell?: number): number {
    return 0;
  }
  getJumpPosition(
    position: CodeEditor.IPosition,
    input_number: number
  ): IJumpPosition {
    return undefined;
  }
}