Problems with scenario management certain keys are not defined in an overwrite config

[euronion]

Version Checks (indicate both or one)

• I have confirmed this bug exists on the lastest release of PyPSA-Eur.

• I have confirmed this bug exists on the current master branch of PyPSA-Eur.

Issue Description

The scenario management does not work if the config without the scenarios applied does not define scenarios.planning_horizon. This even applies if the scenarios overwrite this value.

If scenarios.planning_horizon is set in the default config, everything seems to work properly and the value is overwritten.

edit: There is another issue (bug or undocumented feature) that I came across. The run:name key needs to be set to run:name="all", else the scenario management is also refusing to run all the scenarios. In the examples below, change the run:name to something else and see for yourself...

Reproducible Example

Use the standard PyPSA-Eur setup with config.default.yaml etc. inside the Snakefile. Then create the following additional configuration files:

# scenarios.yaml
2030:
  scenario:
    planning_horizons:
      - 2030

# working.config.yaml
run:
  prefix: ""
  name: "all"
  scenarios:
    enable: true
    file: scenarios.yaml

scenario:
  planning_horizons:
    - "2050"

# not-working.config.yaml
run:
  prefix: ""
  name: "all"
  scenarios:
    enable: true
    file: scenarios.yaml

scenario:
  planning_horizons:
    - ""

Running snakemake --configfile working.config.yaml -n yields a DAG with networks for planning_horizon=2030.

Running snakemake --configfile not-working.config.yaml -n leads to the following error:

MissingInputException in rule make_global_summary in file "<pypsa-eur>/rules/postprocess.smk", line 254:
Missing input files for rule make_global_summary:
    output: results/csvs/costs.csv, results/csvs/capacities.csv, results/csvs/energy.csv, results/csvs/energy_balance.csv, results/csvs/capacity_factors.csv, results/csvs/metrics.csv, results/csvs/curtailment.csv, results/csvs/prices.csv, results/csvs/weighted_prices.csv, results/csvs/market_values.csv, results/csvs/nodal_costs.csv, results/csvs/nodal_capacities.csv, results/csvs/nodal_energy_balance.csv, results/csvs/nodal_capacity_factors.csv
    affected files:
        results/csvs/individual/nodal_capacity_factors_s_50___.csv
        results/csvs/individual/nodal_energy_balance_s_50___.csv
        results/csvs/individual/costs_s_50___.csv
        results/csvs/individual/energy_balance_s_50___.csv
        results/csvs/individual/weighted_prices_s_50___.csv
        results/csvs/individual/prices_s_50___.csv
        results/csvs/individual/metrics_s_50___.csv
        results/csvs/individual/curtailment_s_50___.csv
        results/csvs/individual/nodal_costs_s_50___.csv
        results/csvs/individual/capacity_factors_s_50___.csv
        results/csvs/individual/nodal_capacities_s_50___.csv
        results/csvs/individual/capacities_s_50___.csv
        results/csvs/individual/market_values_s_50___.csv
        results/csvs/individual/energy_s_50___.csv

Expected Behavior

Allow for planning_horizon to be empty.

Installed Versions

Details

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