Format number fix (#10710) (#10711)

* Improvements for format_number func

- Prevent accidental rendering in scientific notation

* Add multiplier argument to format_number

(cherry picked from commit c1bbef1a4d)

Co-authored-by: Oliver <oliver.henry.walters@gmail.com>

src/backend/InvenTree/report/templatetags/report.py

@@ -453,6 +453,7 @@ def render_html_text(text: str, **kwargs):
 def format_number(
     number: Union[int, float, Decimal],
     decimal_places: Optional[int] = None,
+    multiplier: Optional[Union[int, float, Decimal]] = None,
     integer: bool = False,
     leading: int = 0,
     separator: Optional[str] = None,
@@ -462,16 +463,20 @@ def format_number(
     Arguments:
         number: The number to be formatted
         decimal_places: Number of decimal places to render
+        multiplier: Optional multiplier to apply to the number before formatting
         integer: Boolean, whether to render the number as an integer
         leading: Number of leading zeros (default = 0)
         separator: Character to use as a thousands separator (default = None)
     """
     try:
-        number = Decimal(str(number))
+        number = Decimal(str(number).strip())
     except Exception:
         # If the number cannot be converted to a Decimal, just return the original value
         return str(number)
 
+    if multiplier is not None:
+        number *= Decimal(str(multiplier).strip())
+
     if integer:
         # Convert to integer
         number = Decimal(int(number))
@@ -487,7 +492,13 @@ def format_number(
             pass
 
     # Re-encode, and normalize again
-    value = Decimal(number).normalize()
+    # Ensure that the output never uses scientific notation
+    value = Decimal(number)
+    value = (
+        value.quantize(Decimal(1))
+        if value == value.to_integral()
+        else value.normalize()
+    )
 
     if separator:
         value = f'{value:,}'

src/backend/InvenTree/report/test_tags.py

@@ -210,6 +210,14 @@ class ReportTagTest(PartImageTestMixin, InvenTreeTestCase):
         """Simple tests for number formatting tags."""
         fn = report_tags.format_number
 
+        self.assertEqual(fn(None), 'None')
+
+        for i in [1, '1', '1.0000', '  1  ']:
+            self.assertEqual(fn(i), '1')
+
+        for x in ['10.000000', '  10  ', 10.000000, 10]:
+            self.assertEqual(fn(x), '10')
+
         self.assertEqual(fn(1234), '1234')
         self.assertEqual(fn(1234.5678, decimal_places=2), '1234.57')
         self.assertEqual(fn(1234.5678, decimal_places=3), '1234.568')
@@ -218,6 +226,9 @@ class ReportTagTest(PartImageTestMixin, InvenTreeTestCase):
             fn(9988776655.4321, integer=True, separator=' '), '9 988 776 655'
         )
 
+        # Test with multiplier
+        self.assertEqual(fn(1000, multiplier=1.5), '1500')
+
         # Failure cases
         self.assertEqual(fn('abc'), 'abc')
         self.assertEqual(fn(1234.456, decimal_places='a'), '1234.456')