quite a bit of development around get rates input handling

poetry.lock

@@ -135,6 +135,17 @@ files = [
     {file = "colorama-0.4.6.tar.gz", hash = "sha256:08695f5cb7ed6e0531a20572697297273c47b8cae5a63ffc6d6ed5c201be6e44"},
 ]
 
+[[package]]
+name = "currencies"
+version = "2020.12.12"
+description = "Display money format and its filthy currencies, for all money lovers out there."
+optional = false
+python-versions = "<4"
+files = [
+    {file = "currencies-2020.12.12-py3-none-any.whl", hash = "sha256:33b017bd11b0a70707ffa917e80cd8c4e07a1a6b412239ee19c10f145ed5f031"},
+    {file = "currencies-2020.12.12.tar.gz", hash = "sha256:400cf313b8f6f33a59dcc9c9723dbe458eb8ff18a74ad2b79eba8a295a44b556"},
+]
+
 [[package]]
 name = "idna"
 version = "3.7"
@@ -226,4 +237,4 @@ requests = ">=2.19.1"
 [metadata]
 lock-version = "2.0"
 python-versions = "^3.10"
-content-hash = "fc10bcffee4d61f71d09d8ee3ecd62c907cf50c34e802bf747bc0e17770e7646"
+content-hash = "2fea7228b5d6197e7c654a55dfc2415d44e9b6f98abd859a7067910a4fc89571"

pyproject.toml

@@ -11,6 +11,7 @@ click = "^8.1.7"
 python-dotenv = "^1.0.1"
 pyfiglet = "^1.0.2"
 xecd-rates-client = "^1.0.0"
+currencies = "^2020.12.12"
 
 [build-system]
 requires = ["poetry-core"]

tests/tests_cli/test_xe_get_rates.py

@@ -35,15 +35,3 @@ def test_get_rates_breaks_without_output():
     runner = CliRunner()
     result = runner.invoke(get_rates)
     assert result.exit_code == 2
-
-
-def test_get_rates_replaces_future_dates_properly():
-    assert False
-
-
-def test_get_rates_rejects_start_date_after_end_date():
-    assert False
-
-
-def test_get_rates_rejects_invalid_currency_codes():
-    assert False

tests/tests_unit/test_input_handling.py

@@ -0,0 +1,94 @@
+import datetime
+
+import pytest
+from currencies import Currency
+from currencies.exceptions import CurrencyDoesNotExist
+
+from xexe.inputs_handling import handle_get_rates_inputs
+from xexe.utils import DateRange
+
+
+def test_handle_input_rates_works_with_full_correct_inputs():
+    handled_inputs = handle_get_rates_inputs(
+        start_date=datetime.datetime.now(),
+        end_date=datetime.datetime.now() + datetime.timedelta(days=7),
+        currencies="USD,EUR,GBP",
+        dry_run=False,
+        output="test_output.csv",
+    )
+    expected_result = {
+        "date_range": DateRange(
+            start_date=datetime.datetime.now().date(),
+            end_date=(datetime.datetime.now() + datetime.timedelta(days=7)).date(),
+        ),
+        "currencies": {Currency("USD"), Currency("EUR"), Currency("GBP")},
+        "dry_run": False,
+        "output": pathlib.Path("test_output.csv"),
+    }
+    assert handled_inputs == expected_result
+
+
+def test_handle_input_rates_raises_with_bad_currency_code():
+
+    with pytest.raises(CurrencyDoesNotExist):
+        handle_get_rates_inputs(
+            start_date=datetime.datetime.now(),
+            end_date=datetime.datetime.now() + datetime.timedelta(days=7),
+            currencies="not_a_currency,USD,not_this_either",
+            dry_run=False,
+            output="test_output.csv",
+        )
+
+
+def test_handle_input_rates_raises_with_start_date_after_end_date():
+    with pytest.raises(ValueError):
+        handle_get_rates_inputs(
+            start_date=datetime.datetime.now(),
+            end_date=datetime.datetime.now() - datetime.timedelta(days=7),
+            currencies="GBP,USD",
+            dry_run=False,
+            output="test_output.csv",
+        )
+
+
+def test_handle_input_rates_raises_with_output_different_than_csv():
+    with pytest.raises(ValueError):
+        handle_get_rates_inputs(
+            start_date=datetime.datetime.now(),
+            end_date=datetime.datetime.now() + datetime.timedelta(days=7),
+            currencies="GBP,USD",
+            dry_run=False,
+            output="test_output.xlsx",
+        )
+
+
+def test_handle_input_rates_brings_future_end_date_to_today():
+    handled_inputs = handle_get_rates_inputs(
+        start_date=datetime.datetime.now() - datetime.timedelta(days=7),
+        end_date=datetime.datetime.now() + datetime.timedelta(days=7),
+        currencies="USD,EUR,GBP",
+        dry_run=False,
+        output="test_output.csv",
+    )
+
+    assert handled_inputs["date_range"].end_date == datetime.datetime.now().date()
+
+
+def test_handle_input_rates_start_and_end_date_equal_works_fine():
+    handled_inputs = handle_get_rates_inputs(
+        start_date=datetime.datetime.now(),
+        end_date=datetime.datetime.now(),
+        currencies="USD,EUR,GBP",
+        dry_run=False,
+        output="test_output.csv",
+    )
+    expected_result = {
+        "date_range": DateRange(
+            start_date=datetime.datetime.now().date(),
+            end_date=(datetime.datetime.now() + datetime.timedelta(days=7)).date(),
+        ),
+        "currencies": {Currency("USD"), Currency("EUR"), Currency("GBP")},
+        "dry_run": False,
+        "output": "test_output.csv",
+    }
+    assert handled_inputs == expected_result

xexe/cli.py

@@ -74,7 +74,7 @@ def get_rates(
     dry_run: bool,
     output: pathlib.Path,
 ):
-    handle_get_rates_inputs(
+    inputs = handle_get_rates_inputs(
         start_date=start_date,
         end_date=end_date,
         currencies=currencies,

xexe/constants.py

@@ -1,6 +1,10 @@
 import pathlib
 from dataclasses import dataclass
 
+from currencies import Currency
+
+DEFAULT_CURRENCIES = {Currency("EUR"), Currency("GBP"), Currency("USD")}
+
 
 @dataclass
 class PATHS:

xexe/inputs_handling.py

@@ -1,12 +1,51 @@
+import datetime
 import logging
+import pathlib
+from typing import Union
+
+from currencies import Currency
+
+from xexe.constants import DEFAULT_CURRENCIES
+from xexe.utils import DateRange
 
 logger = logging.getLogger()
 
 
-def handle_get_rates_inputs(start_date, end_date, currencies, dry_run, output):
+def handle_get_rates_inputs(
+    start_date: Union[datetime.datetime, datetime.date],
+    end_date: Union[datetime.datetime, datetime.date],
+    currencies: Union[None, str],
+    dry_run: bool,
+    output: Union[str, pathlib.Path],
+):
     logger.info("Handling inputs.")
-    logger.debug(f"Received start_date: {start_date}")
+
-    logger.debug(f"Received end_date: {end_date}")
+    date_range = DateRange(start_date=start_date.date(), end_date=end_date.date())
-    logger.debug(f"Received currencies: {currencies}")
+
-    logger.debug(f"dry_run state: {dry_run}")
+    if date_range.end_date > datetime.datetime.today().date():
-    logger.debug(f"Received output: {output}")
+        date_range.end_date = datetime.datetime.today().date()
+
+    if currencies:
+        # CLI input comes as string of comma-separated currency codes
+        currencies = [currency_code.strip() for currency_code in currencies.split(",")]
+        tmp = [Currency(currency_code) for currency_code in currencies]
+        currencies = tmp
+
+    if currencies is None:
+        currencies = DEFAULT_CURRENCIES
+
+    # The Path constructor is idempotent, so this works equally fine if output
+    # is a string or an actual Path object.
+    output = pathlib.Path(output)
+    if output.suffix != ".csv":
+        raise ValueError("Output must be a .csv file.")
+
+    prepared_inputs = {
+        "date_range": date_range,
+        "currencies": currencies,
+        "dry_run": dry_run,
+        "output": output,
+    }
+
+    logger.debug(prepared_inputs)
+    return prepared_inputs

xexe/utils.py

@@ -0,0 +1,42 @@
+import datetime
+
+
+class DateRange:
+
+    def __init__(self, start_date: datetime.date, end_date: datetime.date):
+        if type(start_date) != datetime.date or type(end_date) != datetime.date:
+            raise TypeError("start_date and end_date must be date objects.")
+
+        if start_date > end_date:
+            raise ValueError("start_date can't be after end_date.")
+
+        self._start_date = start_date
+        self._end_date = end_date
+
+    @property
+    def start_date(self):
+        return self._start_date
+
+    @start_date.setter
+    def start_date(self, value: datetime.date):
+        if type(value) != datetime.date:
+            raise TypeError("start_date must be a date object.")
+
+        if value > self._end_date:
+            raise ValueError("start_date can't be after end_date.")
+
+        self._start_date = value
+
+    @property
+    def end_date(self):
+        return self._end_date
+
+    @end_date.setter
+    def end_date(self, value: datetime.date):
+        if type(value) != datetime.date:
+            raise TypeError("end_date must be a date object.")
+
+        if value < self._start_date:
+            raise ValueError("end_date can't be before start_date.")
+
+        self._end_date = value