Method checkCircularity

core/session.ts:714–743

(actions: ActionProto[])

  }

  private checkCircularity(actions: ActionProto[]) {
    const allActionsByStringifiedTarget = new Map<string, ActionProto>(
      actions.map(action => [targetStringifier.stringify(action.target), action])
    );

    // Type exports for tarjan-graph are unfortunately wrong, so we have to do this minor hack.
    const tarjanGraph: TarjanGraph = new (TarjanGraphConstructor as any)();
    actions.forEach(action => {
      // Declarations cannot have dependencies.
      const cleanedDependencies = (action instanceof dataform.Declaration ||
        !action.dependencyTargets
        ? []
        : action.dependencyTargets
      ).filter(
        dependency => !!allActionsByStringifiedTarget.get(targetStringifier.stringify(dependency))
      );
      tarjanGraph.add(
        targetStringifier.stringify(action.target),
        cleanedDependencies.map(target => targetStringifier.stringify(target))
      );
    });
    const cycles = tarjanGraph.getCycles();
    cycles.forEach(cycle => {
      const firstActionInCycle = allActionsByStringifiedTarget.get(cycle[0].name);
      const message = `Circular dependency detected in chain: [${cycle
        .map(vertex => vertex.name)
        .join(" > ")} > ${targetAsReadableString(firstActionInCycle.target)}]`;
      this.compileError(new Error(message), firstActionInCycle.fileName, firstActionInCycle.target);
    });
  }

  private addTestsToCompiledGraph(actions: Action[]) {
    actions