Merge pull request #67 from Talm28/master

Add IFERROR function + tests

README.rst

@@ -361,7 +361,7 @@ Logical
   +-----------------+--------------+-------+----------+-------+
   | IF              |      *       |   *   |    *     |       |
   +-----------------+--------------+-------+----------+-------+
-  | IFERROR         |              |   *   |    *     |   *   |
+  | IFERROR         |       *      |   *   |    *     |   *   |
   +-----------------+--------------+-------+----------+-------+
   | IFS             |              |   *   |          |       |
   +-----------------+--------------+-------+----------+-------+

tests/xlfunctions/test_logical.py

@@ -52,3 +52,10 @@ def test_NOT_with_direct_values(self):
 
     def test_TRUE(self):
         self.assertTrue(logical.TRUE())
+
+    def test_IFERROR(self):
+        self.assertEqual(logical.IFERROR(10/2,0),5) # Check if value is OK
+        self.assertEqual(logical.IFERROR(10/0,0),0) # Check if value cause error
+        self.assertEqual(logical.IFERROR(10/0,"ERROR"),"ERROR") # Check returning string
+        self.assertEqual(logical.IFERROR(logical.IFERROR(10/0,0) + 1,0),1) # Check nested IFERROR
+

tests/xlfunctions_vs_excel/iferror_test.py

@@ -0,0 +1,37 @@
+from .. import testing
+
+from xlcalculator.xlfunctions import xlerrors
+
+
+class SqrtTest(testing.FunctionalTestCase):
+    filename = "IFERROR.xlsx"
+
+    def test_evaluation_C1(self):
+        self.assertEqual(
+            self.evaluator.get_cell_value('Sheet1!C1!'),
+            self.evaluator.evaluate('Sheet1!C1')
+        )
+
+    def test_evaluation_C2(self):
+        self.assertEqual(
+            self.evaluator.get_cell_value('Sheet1!C2!'),
+            self.evaluator.evaluate('Sheet1!C2')
+        )
+
+    def test_evaluation_C3(self):
+        self.assertEqual(
+            self.evaluator.get_cell_value('Sheet1!C3!'),
+            self.evaluator.evaluate('Sheet1!C3')
+        )
+
+    def test_evaluation_C4(self):
+        self.assertEqual(
+            self.evaluator.get_cell_value('Sheet1!C4!'),
+            self.evaluator.evaluate('Sheet1!C4')
+        )
+
+    def test_evaluation_C5(self):
+        self.assertEqual(
+            self.evaluator.get_cell_value('Sheet1!C5!'),
+            self.evaluator.evaluate('Sheet1!C5')
+        )

xlcalculator/xlfunctions/logical.py

@@ -101,3 +101,15 @@ def TRUE() -> func_xltypes.XlBoolean:
         true-function-7652c6e3-8987-48d0-97cd-ef223246b3fb
     """
     return True
+
+@xl.register()
+@xl.validate_args
+def IFERROR(value: func_xltypes.XlExpr,
+            value_if_error: func_xltypes.XlAnything) -> func_xltypes.XlAnything:
+    """Evaluate value, return value if has no error, otherwise return value_if_error.
+
+    https://support.microsoft.com/en-au/office/iferror-function-c526fd07-caeb-47b8-8bb6-63f3e417f611
+    """
+    if isinstance(value(), xlerrors.ExcelError):
+        return value_if_error
+    return value()