@krassowski/jupyterlab_go_to_definition/lib/languages/r.js

Jump to definition of a variable or function in JupyterLab

import { LanguageWithOptionalSemicolons } from './analyzer';
export class RAnalyzer extends LanguageWithOptionalSemicolons {
    constructor() {
        super(...arguments);
        this.definitionRules = [
            this.isStandaloneAssignment,
            this.isImport,
            this.isForLoop
        ];
    }
    isAssignment(token) {
        return ((token.type === 'operator' && token.value === '=') ||
            (token.type === 'operator arrow' &&
                (token.value === '<-' || token.value === '<<-')));
    }
    // Matching standalone variable assignment:
    isStandaloneAssignment(context) {
        let { previous, next } = context;
        return (
        // standard, leftwards assignments:
        (next.exists && this.isAssignment(next)) ||
            // rightwards assignments:
            (previous.exists &&
                previous.type === 'operator arrow' &&
                (previous.value === '->' || previous.value === '->>')));
    }
    // Matching imports:
    isImport(context) {
        let { previous } = context;
        if (previous.exists &&
            previous.type === 'variable' &&
            (previous.value === 'library' || previous.value === 'require')) {
            return true;
        }
        previous = this.traverse_left(previous, ', ');
        if (previous.exists &&
            previous.value === 'here' &&
            previous.type === 'variable' &&
            previous.previous.value === '::' &&
            previous.previous.previous.value === 'import') {
            return true;
        }
        return false;
    }
    // Matching `for` loop and comprehensions:
    isForLoop(context) {
        let { previous, next } = context;
        return (previous.exists &&
            previous.type === 'keyword' &&
            previous.value === 'for' &&
            next.exists &&
            next.type === 'keyword' &&
            next.value === 'in');
    }
    guessReferencePath(context) {
        let { next } = context;
        if (context.value === 'source') {
            return [next.next.value.slice(0, -1)];
        }
        // TODO for now only works when alt-clicking on ".from"
        // ideally clicking on the file name would be preferred
        return [next.next.next.value.slice(0, -1)];
    }
    isCrossFileReference(context) {
        // case: "source('test.R')" - clicking on source will open test.R
        let { next } = context;
        if (context.type === 'variable' &&
            context.value === 'source' &&
            next.exists &&
            (next.value === "'" || next.value === '"') &&
            next.next.exists) {
            return true;
        }
        if (this.isImport(context.previous)) {
            return true;
        }
        return false;
    }
}
//# sourceMappingURL=r.js.map