Fix bug in string-representation of dilution plans involving serial d…

…ilutions (#49)

* Write regression test against #48

* Fix bug in `DilutionPlan` text representation

It affected all text-representation of dilution plans
involving serial dilutions.

Closes #48

robotools/__init__.py

@@ -11,4 +11,4 @@
 )
 from .utils import DilutionPlan, get_trough_wells
 
-__version__ = "1.7.2"
+__version__ = "1.7.3"

robotools/test_utils.py

@@ -40,6 +40,27 @@ def test_repr(self) -> None:
         assert isinstance(out, str)
         return
 
+    def test_issue_48(self):
+        """Columns are named 1-based, therefore the "from column" must be too."""
+        plan = DilutionPlan(xmin=0.3, xmax=30, stock=30, R=1, C=3, mode="log", vmax=100, min_transfer=10)
+        np.testing.assert_allclose(plan.x, [[30, 3, 0.3]])
+        # Reformat instructions for easier equals comparison
+        instructions = [(col, dsteps, pfrom, float(tvols)) for col, dsteps, pfrom, tvols in plan.instructions]
+        assert instructions == [
+            (0, 0, "stock", 100.0),
+            (1, 0, "stock", 10.0),  # The previous column is equal to the stock!
+            (2, 1, 1, 10.0),
+        ]
+        plan_s = str(plan)
+        lines = plan_s.split("\n")
+        assert "Prepare column 1" in lines[1]
+        assert "Prepare column 2" in lines[2]
+        assert "Prepare column 3" in lines[3]
+        assert "from stock" in lines[1]
+        assert "from stock" in lines[2]
+        assert "from column 2" in lines[3]
+        pass
+
     def test_linear_plan(self) -> None:
         plan = DilutionPlan(xmin=1, xmax=10, R=10, C=1, stock=20, mode="linear", vmax=1000, min_transfer=20)
 

robotools/utils.py

@@ -159,7 +159,8 @@ def __repr__(self) -> str:
             if dsteps == 0:
                 output += "stock"
             else:
-                output += f"column {src}"
+                assert isinstance(src, int)
+                output += f"column {src + 1}"
             output += f" and fill up to {self.vmax[c]} µL"
             if dsteps > 0:
                 output += f" ({dsteps} serial dilutions)"