Only read text files that look like entries when opening folder journal (#1697)

* Add text file that should be ignored to basic test folder journal. Makes tons of tests fail
* Add additional files that should be ignored by FolderJournal
* Ignore all files in folder journal except year/month/day.txt
* Completely remake get_files in FolderJournal:
- move get_files into FolderJournal class and add underscore prefix
- create iterables to get for year/month folders and day files
- make year/month/day file reading strict: only exact expected months and days out of all possible months and days
* Restore accidentally-deleted self.sort() line
* Use match instead of string comparison to be os-agnostic
* Explicitly declare static methods
* Filter with glob first for max performance
* Explicitly check for valid dates in FolderJournal and add unit test
* Remove unneeded jrnl import
* Clean up method comment and add type hints
* Add is_valid_date unit test
* Elucidate comment

Co-authored-by: Jonathan Wren <jonathan@nowandwren.com>

7 files changed, 153 insertions, 16 deletions

diff --git a/jrnl/journals/FolderJournal.py b/jrnl/journals/FolderJournal.py
index 88fa21e1..0d497fb8 100644
--- a/jrnl/journals/FolderJournal.py
+++ b/jrnl/journals/FolderJournal.py
@@ -2,8 +2,8 @@
 # License: https://www.gnu.org/licenses/gpl-3.0.html
 
 import codecs
-import fnmatch
 import os
+import pathlib
 from typing import TYPE_CHECKING
 
 from jrnl import time
@@ -13,14 +13,11 @@ from .Journal import Journal
 if TYPE_CHECKING:
     from jrnl.journals import Entry
 
-
-def get_files(journal_config: str) -> list[str]:
-    """Searches through sub directories starting with journal_config and find all text files"""
-    filenames = []
-    for root, dirnames, f in os.walk(journal_config):
-        for filename in fnmatch.filter(f, "*.txt"):
-            filenames.append(os.path.join(root, filename))
-    return filenames
+# glob search patterns for folder/file structure
+DIGIT_PATTERN = "[0123456789]"
+YEAR_PATTERN = DIGIT_PATTERN * 4
+MONTH_PATTERN = "[01]" + DIGIT_PATTERN
+DAY_PATTERN = "[0123]" + DIGIT_PATTERN + ".txt"
 
 
 class Folder(Journal):
@@ -35,12 +32,15 @@ class Folder(Journal):
     def open(self) -> "Folder":
         filenames = []
         self.entries = []
-        filenames = get_files(self.config["journal"])
-        for filename in filenames:
-            with codecs.open(filename, "r", "utf-8") as f:
-                journal = f.read()
-                self.entries.extend(self._parse(journal))
-        self.sort()
+
+        if os.path.exists(self.config["journal"]):
+            filenames = Folder._get_files(self.config["journal"])
+            for filename in filenames:
+                with codecs.open(filename, "r", "utf-8") as f:
+                    journal = f.read()
+                    self.entries.extend(self._parse(journal))
+            self.sort()
+
         return self
 
     def write(self) -> None:
@@ -81,7 +81,7 @@ class Folder(Journal):
                 journal_file.write(journal)
         # look for and delete empty files
         filenames = []
-        filenames = get_files(self.config["journal"])
+        filenames = Folder._get_files(self.config["journal"])
         for filename in filenames:
             if os.stat(filename).st_size <= 0:
                 os.remove(filename)
@@ -119,3 +119,39 @@ class Folder(Journal):
 
         self.increment_change_counts_by_edit(mod_entries)
         self.entries = mod_entries
+
+    @staticmethod
+    def _get_files(journal_path: str) -> list[str]:
+        """Searches through sub directories starting with journal_path and find all text files that look like entries"""
+        for year_folder in Folder._get_year_folders(pathlib.Path(journal_path)):
+            for month_folder in Folder._get_month_folders(year_folder):
+                yield from Folder._get_day_files(month_folder)
+
+    @staticmethod
+    def _get_year_folders(path: pathlib.Path) -> list[pathlib.Path]:
+        for child in path.glob(YEAR_PATTERN):
+            if child.is_dir():
+                yield child
+        return
+
+    @staticmethod
+    def _get_month_folders(path: pathlib.Path) -> list[pathlib.Path]:
+        for child in path.glob(MONTH_PATTERN):
+            if int(child.name) > 0 and int(child.name) <= 12 and path.is_dir():
+                yield child
+        return
+
+    @staticmethod
+    def _get_day_files(path: pathlib.Path) -> list[str]:
+        for child in path.glob(DAY_PATTERN):
+            if (
+                int(child.stem) > 0
+                and int(child.stem) <= 31
+                and time.is_valid_date(
+                    year=int(path.parent.name),
+                    month=int(path.name),
+                    day=int(child.stem),
+                )
+                and child.is_file()
+            ):
+                yield str(child)
diff --git a/jrnl/time.py b/jrnl/time.py
index 514d94f2..dd6fcb0f 100644
--- a/jrnl/time.py
+++ b/jrnl/time.py
@@ -89,3 +89,11 @@ def parse(
     if dt.days < -28 and not year_present:
         date = date.replace(date.year - 1)
     return date
+
+
+def is_valid_date(year: int, month: int, day: int) -> bool:
+    try:
+        datetime.datetime(year, month, day)
+        return True
+    except ValueError:
+        return False
diff --git a/tests/data/journals/basic_folder/2020/09/should-be-ignored.txt b/tests/data/journals/basic_folder/2020/09/should-be-ignored.txt
new file mode 100644
index 00000000..4807e608
--- /dev/null
+++ b/tests/data/journals/basic_folder/2020/09/should-be-ignored.txt
@@ -0,0 +1,4 @@
+[2022-03-02 9:25:00 AM] This file should be ignored (month)
+This text file is in a folder journal's month directory ("2020/09"), but it's not in the file name format used by jrnl for folder journal entries, so it should be ignored.
+
+This file should not ever appear in a test.
\ No newline at end of file
diff --git a/tests/data/journals/basic_folder/2020/should-be-ignored.txt b/tests/data/journals/basic_folder/2020/should-be-ignored.txt
new file mode 100644
index 00000000..24f57815
--- /dev/null
+++ b/tests/data/journals/basic_folder/2020/should-be-ignored.txt
@@ -0,0 +1,4 @@
+[2022-03-02 9:25:00 AM] This file should be ignored (year)
+This text file is in a folder journal's year directory ("2020"), but it's not in the file name format used by jrnl for folder journal entries, so it should be ignored.
+
+This file should not ever appear in a test.
\ No newline at end of file
diff --git a/tests/data/journals/basic_folder/should-be-ignored.txt b/tests/data/journals/basic_folder/should-be-ignored.txt
new file mode 100644
index 00000000..35b7ae2f
--- /dev/null
+++ b/tests/data/journals/basic_folder/should-be-ignored.txt
@@ -0,0 +1,4 @@
+[2022-03-02 9:25:00 AM] This file should be ignored (root)
+This text file is in a folder journal's root directory, but it's not in the file name format used by jrnl for folder journal entries, so it should be ignored.
+
+This file should not ever appear in a test.
\ No newline at end of file
diff --git a/tests/unit/test_journals_folder_journal.py b/tests/unit/test_journals_folder_journal.py
new file mode 100644
index 00000000..09a3535f
--- /dev/null
+++ b/tests/unit/test_journals_folder_journal.py
@@ -0,0 +1,59 @@
+# Copyright © 2012-2023 jrnl contributors
+# License: https://www.gnu.org/licenses/gpl-3.0.html
+
+import pathlib
+from unittest import mock
+
+import pytest
+
+from jrnl.journals.FolderJournal import Folder
+
+
+@pytest.mark.parametrize(
+    "inputs_and_outputs",
+    [
+        [
+            "/2020/01",
+            ["02.txt", "03.txt", "31.txt"],
+            ["/2020/01/02.txt", "/2020/01/03.txt", "/2020/01/31.txt"],
+        ],
+        [
+            "/2020/02",  # leap year
+            ["02.txt", "03.txt", "28.txt", "29.txt", "31.txt", "39.txt"],
+            [
+                "/2020/02/02.txt",
+                "/2020/02/03.txt",
+                "/2020/02/28.txt",
+                "/2020/02/29.txt",
+            ],
+        ],
+        [
+            "/2100/02",  # not a leap year
+            ["01.txt", "28.txt", "29.txt", "39.txt"],
+            ["/2100/02/01.txt", "/2100/02/28.txt"],
+        ],
+        [
+            "/2023/04",
+            ["29.txt", "30.txt", "31.txt", "39.txt"],
+            ["/2023/04/29.txt", "/2023/04/30.txt"],
+        ],
+    ],
+)
+def test_get_day_files_expected_filtering(inputs_and_outputs):
+    year_month_path, glob_filenames, expected_output = inputs_and_outputs
+
+    year_month_path = pathlib.Path(year_month_path)
+
+    glob_files = map(lambda x: year_month_path / x, glob_filenames)
+    expected_output = list(map(lambda x: str(pathlib.PurePath(x)), expected_output))
+
+    with (
+        mock.patch("pathlib.Path.glob", return_value=glob_files),
+        mock.patch.object(pathlib.Path, "is_file", return_value=True),
+    ):
+        actual_output = list(Folder._get_day_files(year_month_path))
+        actual_output.sort()
+
+        expected_output.sort()
+
+        assert actual_output == expected_output
diff --git a/tests/unit/test_time.py b/tests/unit/test_time.py
index 8bc5ac8e..1901a4dc 100644
--- a/tests/unit/test_time.py
+++ b/tests/unit/test_time.py
@@ -3,6 +3,8 @@
 
 import datetime
 
+import pytest
+
 from jrnl import time
 
 
@@ -20,3 +22,23 @@ def test_default_minute_is_added():
         default_minute=30,
         bracketed=False,
     ) == datetime.datetime(2020, 6, 20, 0, 30)
+
+
+@pytest.mark.parametrize(
+    "inputs",
+    [
+        [2000, 2, 29, True],
+        [2023, 1, 0, False],
+        [2023, 1, 1, True],
+        [2023, 4, 31, False],
+        [2023, 12, 31, True],
+        [2023, 12, 32, False],
+        [2023, 13, 1, False],
+        [2100, 2, 27, True],
+        [2100, 2, 28, True],
+        [2100, 2, 29, False],
+    ],
+)
+def test_is_valid_date(inputs):
+    year, month, day, expected_result = inputs
+    assert time.is_valid_date(year, month, day) == expected_result