test(units): increase coverage

Author: tmlmt

src/units.ts

@@ -337,7 +337,7 @@ export function addQuantities(q1: Quantity, q2: Quantity): Quantity {
     return addQuantityValuesAndSetUnit(v1, v2, q1.unit);
   }
 
-  // Case 4: the two quantities do not have the same unit
+  // Case 4: the two quantities have different units of known type
   if (unit1Def && unit2Def) {
     // Case 4.1: different unit type => we can't add quantities
 
@@ -373,5 +373,6 @@ export function addQuantities(q1: Quantity, q2: Quantity): Quantity {
     );
   }
 
+  // Case 5: the two quantities have different units of unknown type
   throw new IncompatibleUnitsError(q1.unit, q2.unit);
 }

test/units.test.ts

@@ -141,6 +141,90 @@ describe("addQuantities", () => {
     });
   });
 
+  it("should also work when at least one value is a range", () => {
+    expect(
+      addQuantities(
+        {
+          value: {
+            type: "range",
+            min: { type: "decimal", value: 100 },
+            max: { type: "decimal", value: 200 },
+          },
+          unit: "g",
+        },
+        {
+          value: {
+            type: "range",
+            min: { type: "decimal", value: 10 },
+            max: { type: "decimal", value: 20 },
+          },
+          unit: "g",
+        },
+      ),
+    ).toEqual({
+      value: {
+        type: "range",
+        min: { type: "decimal", value: 110 },
+        max: { type: "decimal", value: 220 },
+      },
+      unit: "g",
+    });
+
+    expect(
+      addQuantities(
+        {
+          value: {
+            type: "fixed",
+            value: { type: "decimal", value: 100 },
+          },
+          unit: "g",
+        },
+        {
+          value: {
+            type: "range",
+            min: { type: "decimal", value: 10 },
+            max: { type: "decimal", value: 20 },
+          },
+          unit: "g",
+        },
+      ),
+    ).toEqual({
+      value: {
+        type: "range",
+        min: { type: "decimal", value: 110 },
+        max: { type: "decimal", value: 120 },
+      },
+      unit: "g",
+    });
+
+    expect(
+      addQuantities(
+        {
+          value: {
+            type: "range",
+            min: { type: "decimal", value: 10 },
+            max: { type: "decimal", value: 20 },
+          },
+          unit: "g",
+        },
+        {
+          value: {
+            type: "fixed",
+            value: { type: "decimal", value: 100 },
+          },
+          unit: "g",
+        },
+      ),
+    ).toEqual({
+      value: {
+        type: "range",
+        min: { type: "decimal", value: 110 },
+        max: { type: "decimal", value: 120 },
+      },
+      unit: "g",
+    });
+  });
+
   it("should add compatible metric units and convert to largest", () => {
     expect(
       addQuantities(
@@ -271,6 +355,18 @@ describe("addQuantities", () => {
         },
       ),
     ).toThrow(IncompatibleUnitsError);
+    expect(() =>
+      addQuantities(
+        {
+          value: { type: "fixed", value: { type: "decimal", value: 100 } },
+          unit: "g",
+        },
+        {
+          value: { type: "fixed", value: { type: "decimal", value: 1 } },
+          unit: "bag",
+        },
+      ),
+    ).toThrow(IncompatibleUnitsError);
   });
 
   it("should add quantities defined as ranges", () => {