Merge pull request #1080 from oemof/revision/replace-constraint-tests

Replaces lp diff constraint tests by granular unit tests for functionality.

Reasoning:
- The LP files depend on Pyomo internals, thus they change when Pyomo changes things.
- They include tests for stuff from multiple parts of the code. For example, if I change the constraint formulation for the Bus, every constraint test needs to be rewritten, not only the one for the Bus.
- They are hard to understand (for many) and failed tests are hard to fix. The latter is particularly because of the undefined order of lines, so that just looking at a diff will not tell the difference: Constraints might be in a different order but still the same.

These unit tests still use Pyomo but the results are independent from the back-end. They are rather easy to understand (rather trivial test examples), and even internal constraint formulations can be changed without breaking the test, so it really tests for the specified functionally not the implementation.

.github/workflows/tox_pytests.yml

@@ -34,7 +34,7 @@ jobs:
       run: tox
 
     - name: Check test coverage
-      run: coverage report -m --fail-under=${{ matrix.vcs == 'bzr' && 89 || 90 }}
+      run: coverage report -m --fail-under=${{ matrix.vcs == 'bzr' && 84 || 85 }}
 
     - name: Report to coveralls
       run: coveralls

src/oemof/solph/__init__.py

@@ -8,8 +8,8 @@
 from . import processing
 from . import views
 from ._energy_system import EnergySystem
-from ._energy_system import create_time_index
 from ._groupings import GROUPINGS
+from ._helpers import create_time_index
 from ._models import Model
 from ._options import Investment
 from ._options import NonConvex

src/oemof/solph/_console_scripts.py

@@ -18,7 +18,7 @@
 from oemof import solph
 
 
-def check_oemof_installation(silent=False):
+def _check_oemof_installation(solvers):
     logging.disable(logging.CRITICAL)
 
     date_time_index = pd.date_range("1/1/2012", periods=6, freq="h")
@@ -48,22 +48,38 @@ def check_oemof_installation(silent=False):
     om = solph.Model(energysystem)
 
     # check solvers
-    solver = dict()
-    for s in ["cbc", "glpk", "gurobi", "cplex"]:
+    solver_status = dict()
+    for s in solvers:
         try:
             om.solve(solver=s)
-            solver[s] = "working"
+            solver_status[s] = True
         except Exception:
-            solver[s] = "not working"
-
-    if not silent:
-        print()
-        print("*****************************")
-        print("Solver installed with oemof:")
-        print()
-        for s, t in solver.items():
-            print("{0}: {1}".format(s, t))
-        print()
-        print("*****************************")
-        print("oemof successfully installed.")
-        print("*****************************")
+            solver_status[s] = False
+
+    return solver_status
+
+
+def check_oemof_installation():
+
+    solvers_to_test = ["cbc", "glpk", "gurobi", "cplex"]
+
+    solver_status = _check_oemof_installation(solvers_to_test)
+
+    print_text = (
+        "***********************************\n"
+        "Solver installed with oemof.solph:\n"
+        "\n"
+    )
+    for solver, works in solver_status.items():
+        if works:
+            print_text += f"{solver}: installed and working\n"
+        else:
+            print_text += f"{solver}: not installed/ not working\n"
+    print_text += (
+        "\n"
+        "***********************************\n"
+        "oemof.solph successfully installed.\n"
+        "***********************************\n"
+    )
+
+    print(print_text)

src/oemof/solph/_energy_system.py

@@ -14,8 +14,6 @@
 
 """
 
-import calendar
-import datetime
 import warnings
 
 import numpy as np
@@ -244,71 +242,3 @@ def get_period_duration(self, period):
             - self.periods[period].min().year
             + 1
         )
-
-
-def create_time_index(
-    year: int = None,
-    interval: float = 1,
-    number: int = None,
-    start: datetime.datetime or datetime.date = None,
-):
-    """
-    Create a datetime index for one year.
-
-    Notes
-    -----
-    To create 8760 hourly intervals for a non leap year a datetime index with
-    8761 time points need to be created. So the number of time steps is always
-    the number of intervals plus one.
-
-    Parameters
-    ----------
-    year : int, datetime
-        The year of the index. If number and start is set the year parameter is
-        ignored.
-    interval : float
-        The time interval in hours e.g. 0.5 for 30min or 2 for a two hour
-        interval (default: 1).
-    number : int
-        The number of time intervals. By default number is calculated to create
-        an index of one year. For a shorter or longer period the number of
-        intervals can be set by the user.
-    start : datetime.datetime or datetime.date
-        Optional start time. If start is not set, 00:00 of the first day of
-        the given year is the start time.
-
-    Examples
-    --------
-    >>> len(create_time_index(2014))
-    8761
-    >>> len(create_time_index(2012))  # leap year
-    8785
-    >>> len(create_time_index(2014, interval=0.5))
-    17521
-    >>> len(create_time_index(2014, interval=0.5, number=10))
-    11
-    >>> len(create_time_index(2014, number=10))
-    11
-    >>> str(create_time_index(2014, interval=0.5, number=10)[-1])
-    '2014-01-01 05:00:00'
-    >>> str(create_time_index(2014, interval=2, number=10)[-1])
-    '2014-01-01 20:00:00'
-    """
-    if number is None:
-        if calendar.isleap(year):
-            hoy = 8784
-        else:
-            hoy = 8760
-        number = round(hoy / interval)
-    if start is None:
-        start = f"1/1/{year}"
-    try:
-        time_index = pd.date_range(
-            start, periods=number + 1, freq=f"{interval}h"
-        )
-    except ValueError:
-        # Pandas <2.2 compatibility
-        time_index = pd.date_range(
-            start, periods=number + 1, freq=f"{interval}H"
-        )
-    return time_index

src/oemof/solph/_helpers.py

@@ -15,8 +15,11 @@
 
 """
 
+import calendar
+import datetime
 from warnings import warn
 
+import pandas as pd
 from oemof.tools import debugging
 
 
@@ -45,3 +48,76 @@ def warn_if_missing_attribute(obj, attribute):
         msg.format(attribute, obj.label, type(obj)),
         debugging.SuspiciousUsageWarning,
     )
+
+
+def create_time_index(
+    year: int = None,
+    interval: float = 1,
+    number: int = None,
+    start: datetime.date = None,
+):
+    """
+    Create a datetime index for one year.
+
+    Notes
+    -----
+    To create 8760 hourly intervals for a non leap year a datetime index with
+    8761 time points need to be created. So the number of time steps is always
+    the number of intervals plus one.
+
+    Parameters
+    ----------
+    year : int, datetime
+        The year of the index.
+        Used to automatically set start and number for the specific year.
+    interval : float
+        The time interval in hours e.g. 0.5 for 30min or 2 for a two hour
+        interval (default: 1).
+    number : int
+        The number of time intervals. By default number is calculated to create
+        an index of one year. For a shorter or longer period the number of
+        intervals can be set by the user.
+    start : datetime.datetime or datetime.date
+        Optional start time. If start is not set, 00:00 of the first day of
+        the given year is the start time.
+
+    Examples
+    --------
+    >>> len(create_time_index(2014))
+    8761
+    >>> len(create_time_index(2012))  # leap year
+    8785
+    >>> len(create_time_index(2014, interval=0.5))
+    17521
+    >>> len(create_time_index(2014, interval=0.5, number=10))
+    11
+    >>> len(create_time_index(2014, number=10))
+    11
+    >>> str(create_time_index(2014, interval=0.5, number=10)[-1])
+    '2014-01-01 05:00:00'
+    >>> str(create_time_index(2014, interval=2, number=10)[-1])
+    '2014-01-01 20:00:00'
+    """
+    if number is None:
+        if calendar.isleap(year):
+            hours_in_year = 8784
+        else:
+            hours_in_year = 8760
+        number = round(hours_in_year / interval)
+    if start is not None:
+        if year is not None:
+            raise ValueError(
+                "Arguments 'start' and 'year' are mutually exclusive."
+            )
+    else:
+        start = f"1/1/{year}"
+    try:
+        time_index = pd.date_range(
+            start, periods=number + 1, freq=f"{interval}h"
+        )
+    except ValueError:
+        # Pandas <2.2 compatibility
+        time_index = pd.date_range(
+            start, periods=number + 1, freq=f"{interval}H"
+        )
+    return time_index