refs #278 Unit Test example for ProgressAnimate

Not perfect yet, but shows the basic concepts of testing for both no failures and expected failures.  I tried to fix things in ProgressAnimate as I went along so that hopefully you can see the correlation between what was being tested, and the fixes that went in to pass the tests.

If you haven't used pytest before, there's a few things to do:
- pip install pytest
- make sure pysimplesql is reachable as a module.  The easiest way is to do a local installation by running `pip -e .` in the pysimplesql root directory
- from the commandline, run `pytest` to run all tests.  Or you can run tests for a specific file, I.e. `pytest progressanimate_test.py`

Author: PySimpleSQL

examples/MSAccess_examples/install_java.py

@@ -6,12 +6,17 @@
 run.  This also serves as an example to automatically download a local Java installation
 for your own projects.
 """
-import jdk
 import os
 import pysimplesql as ss
 import PySimpleGUI as sg
 import subprocess
 
+try:
+    import jdk
+except ModuleNotFoundError:
+    sg.popup_error("You must `pip install install-jdk` to use this example")
+    exit(0)
+
 
 # -------------------------------------------------
 # ROUTINES TO INSTALL JAVA IF USER DOES NOT HAVE IT

pysimplesql/pysimplesql.py

@@ -66,7 +66,6 @@
 from time import sleep, time  # threaded popup
 from typing import Callable, Dict, List, Optional, Tuple, Type, TypedDict, Union  # docs
 
-import jpype  # pip install JPype1
 import PySimpleGUI as sg
 
 # Wrap optional imports so that pysimplesql can be imported as a single file if desired:
@@ -91,38 +90,6 @@
     }
     # fmt: on
 
-# Load database backends if present
-supported_databases = ["SQLite3", "MySQL", "PostgreSQL", "Flatfile", "Sqlserver"]
-failed_modules = 0
-try:
-    import sqlite3
-except ModuleNotFoundError:
-    failed_modules += 1
-try:
-    import mysql.connector  # mysql-connector-python
-except ModuleNotFoundError:
-    failed_modules += 1
-try:
-    import psycopg2
-    import psycopg2.extras
-except ModuleNotFoundError:
-    failed_modules += 1
-try:
-    import csv
-except ModuleNotFoundError:
-    failed_modules += 1
-try:
-    import pyodbc
-except ModuleNotFoundError:
-    failed_modules += 1
-
-if failed_modules == len(supported_databases):
-    RuntimeError(
-        f"You muse have at least one of the following databases installed to use "
-        f"PySimpleSQL:\n{', '.join(supported_databases)} "
-    )
-
-
 logger = logging.getLogger(__name__)
 
 # ---------------------------
@@ -5335,6 +5302,11 @@ class LanguagePack:
         # Quick Editor
         # ------------------------------------------------------------------------------
         "quick_edit_title": "Quick Edit - {data_key}",
+        # ------------------------------------------------------------------------------
+        # Error when importing module for driver
+        # ------------------------------------------------------------------------------
+        "import_module_failed_title": "Problem importing module",
+        "import_module_failed": "Unable to import module neccessary for {name}\nException: {exception}\n\nTry `pip install {requires}`",  # fmt: skip # noqa: E501
     }
     """
     Default LanguagePack.
@@ -6150,6 +6122,7 @@ class SQLDriver:
     def __init__(
         self,
         name: str,
+        requires: List[str],
         placeholder="%s",
         table_quote="",
         column_quote="",
@@ -6163,6 +6136,7 @@ def __init__(
         # Be sure to call super().__init__() in derived class!
         self.con = None
         self.name = name
+        self.requires = requires
         self._check_reserved_keywords = True
         self.win_pb = ProgressBar(
             lang.sqldriver_init.format_map(LangFormat(name=name)), 100
@@ -6187,6 +6161,17 @@ def __init__(
         # override this in derived __init__() (defaults to single quotes)
         self.quote_value_char = value_quote
 
+    def import_failed(self, exception) -> None:
+        popup = Popup()
+        requires = ", ".join(self.requires)
+        popup.ok(
+            lang.import_module_failed_title,
+            lang.import_module_failed.format_map(
+                LangFormat(name=self.name, requires=requires, exception=exception)
+            ),
+        )
+        exit(0)
+
     def check_reserved_keywords(self, value: bool) -> None:
         """
         SQLDrivers can check to make sure that field names respect their own reserved
@@ -6649,11 +6634,14 @@ def __init__(
     ):
         super().__init__(
             name="SQLite",
+            requires=["sqlite3"],
             placeholder="?",
             table_quote='"',
             column_quote='"',
         )
 
+        self.import_required_modules()
+
         new_database = False
         if db_path is not None:
             logger.info(f"Opening database: {db_path}")
@@ -6682,6 +6670,13 @@ def __init__(
         self.db_path = db_path
         self.win_pb.close()
 
+    def import_required_modules(self):
+        global sqlite3  # noqa PLW0603
+        try:
+            import sqlite3
+        except ModuleNotFoundError as e:
+            self.import_failed(e)
+
     def connect(self, database):
         self.con = sqlite3.connect(database)
 
@@ -6850,9 +6845,13 @@ def __init__(
         # First up the SQLite driver that we derived from
         super().__init__(":memory:")  # use an in-memory database
 
-        # Store our Flatfile-specific information
+        # Change Sqlite Sqldriver init set values to Flatfile-specific
         self.name = "Flatfile"
+        self.requires = ["csv,sqlite3"]
         self.placeholder = "?"  # update
+
+        self.import_required_modules()
+
         self.connect(":memory:")
         self.file_path = file_path
         self.delimiter = delimiter
@@ -6917,6 +6916,15 @@ def __init__(
         self.commit()  # commit them all at the end
         self.win_pb.close()
 
+    def import_required_modules(self):
+        global csv  # noqa PLW0603
+        global sqlite3  # noqa PLW0603
+        try:
+            import csv
+            import sqlite3
+        except ModuleNotFoundError as e:
+            self.import_failed(e)
+
     def save_record(
         self, dataset: DataSet, changed_row: dict, where_clause: str = None
     ) -> ResultSet:
@@ -6969,9 +6977,11 @@ class Mysql(SQLDriver):
     def __init__(
         self, host, user, password, database, sql_script=None, sql_commands=None
     ):
-        super().__init__(name="MySQL")
+        super().__init__(name="MySQL", requires=["mysql-connector-python"])
+
+        self.import_required_modules()
 
-        self.name = "MySQL"
+        self.name = "MySQL"  # is this redundant?
         self.host = host
         self.user = user
         self.password = password
@@ -6992,6 +7002,13 @@ def __init__(
 
         self.win_pb.close()
 
+    def import_required_modules(self):
+        global mysql  # noqa PLW0603
+        try:
+            import mysql.connector
+        except ModuleNotFoundError as e:
+            self.import_failed(e)
+
     def connect(self, retries=3):
         attempt = 0
         while attempt < retries:
@@ -7168,7 +7185,11 @@ def __init__(
         sql_commands=None,
         sync_sequences=False,
     ):
-        super().__init__(name="Postgres", table_quote='"')
+        super().__init__(
+            name="Postgres", requires=["psycopg2", "psycopg2.extras"], table_quote='"'
+        )
+
+        self.import_required_modules()
 
         self.host = host
         self.user = user
@@ -7223,6 +7244,14 @@ def __init__(
             self.execute_script(sql_script)
         self.win_pb.close()
 
+    def import_required_modules(self):
+        global psycopg2  # noqa PLW0603
+        try:
+            import psycopg2
+            import psycopg2.extras
+        except ModuleNotFoundError as e:
+            self.import_failed(e)
+
     def connect(self, retries=3):
         attempt = 0
         while attempt < retries:
@@ -7425,7 +7454,9 @@ def __init__(
     ):
         super().__init__(name="Sqlserver", table_quote="[]", placeholder="?")
 
-        self.name = "Sqlserver"
+        self.import_required_modules()
+
+        self.name = "Sqlserver"  # is this redundant?
         self.host = host
         self.user = user
         self.password = password
@@ -7445,6 +7476,13 @@ def __init__(
 
         self.win_pb.close()
 
+    def import_required_modules(self):
+        global pyodbc  # noqa PLW0603
+        try:
+            import pyodbc
+        except ModuleNotFoundError as e:
+            self.import_failed(e)
+
     def connect(self, retries=3, timeout=3):
         attempt = 0
         while attempt < retries:
@@ -7608,13 +7646,25 @@ class MSAccess(SQLDriver):
     """
 
     def __init__(self, database_file):
-        super().__init__(name="MSAccess", table_quote="[]", placeholder="?")
+        super().__init__(
+            name="MSAccess", requires=["Jype1"], table_quote="[]", placeholder="?"
+        )
+
+        self.import_required_modules()
+
         self.database_file = database_file
         self.con = self.connect()
 
     import os
     import sys
 
+    def import_required_modules(self):
+        global jpype  # noqa PLW0603
+        try:
+            import jpype  # pip install JPype1
+        except ModuleNotFoundError as e:
+            self.import_failed(e)
+
     def connect(self):
         # Get the path to the 'lib' folder
         current_path = os.path.dirname(os.path.abspath(__file__))