feat(ShoppingList): add a recipe with either a factor or a number of servings for scaling (#45)

* test(shopping_list): group tests for readability

* feat(ShoppingList): add a recipe with either a factor or a number of servings for scaling

Currently, it is only possible to scale with a scaling factor (e.g. x2) a recipe to add in the shopping list. This introduces the possibility to use a number of servings for scaling, instead

Deprecation: the call signature `add_recipe(recipe: Recipe, factor?: number) is now deprecated and will be removed in v3

Author: tmlmt

src/classes/shopping_list.ts

@@ -64,8 +64,14 @@ export class ShoppingList {
 
   private calculate_ingredients() {
     this.ingredients = [];
-    for (const { recipe, factor } of this.recipes) {
-      const scaledRecipe = factor === 1 ? recipe : recipe.scaleBy(factor);
+    for (const addedRecipe of this.recipes) {
+      let scaledRecipe: Recipe;
+      if ("factor" in addedRecipe) {
+        const { recipe, factor } = addedRecipe;
+        scaledRecipe = factor === 1 ? recipe : recipe.scaleBy(factor);
+      } else {
+        scaledRecipe = addedRecipe.recipe.scaleTo(addedRecipe.servings);
+      }
 
       for (const ingredient of scaledRecipe.ingredients) {
         // Do not add hidden ingredients to the shopping list
@@ -123,14 +129,37 @@ export class ShoppingList {
     }
   }
 
+  /**
+   * Adds a recipe to the shopping list, then automatically
+   * recalculates the quantities and recategorize the ingredients.
+   * @param recipe - The recipe to add.
+   * @param scaling - The scaling option for the recipe. Can be either a factor or a number of servings
+   */
+  add_recipe(
+    recipe: Recipe,
+    scaling?: { factor: number } | { servings: number },
+  ): void;
   /**
    * Adds a recipe to the shopping list, then automatically
    * recalculates the quantities and recategorize the ingredients.
    * @param recipe - The recipe to add.
    * @param factor - The factor to scale the recipe by.
+   * @deprecated since v2.0.3. Use the other call signature with `scaling` instead. Will be removed in v3
    */
-  add_recipe(recipe: Recipe, factor: number = 1) {
-    this.recipes.push({ recipe, factor });
+  add_recipe(recipe: Recipe, factor?: number): void;
+  add_recipe(
+    recipe: Recipe,
+    scaling?: { factor: number } | { servings: number } | number,
+  ): void {
+    if (typeof scaling === "number" || scaling === undefined) {
+      this.recipes.push({ recipe, factor: scaling ?? 1 });
+    } else {
+      if ("factor" in scaling) {
+        this.recipes.push({ recipe, factor: scaling.factor });
+      } else {
+        this.recipes.push({ recipe, servings: scaling.servings });
+      }
+    }
     this.calculate_ingredients();
     this.categorize();
   }

src/index.ts

@@ -25,6 +25,8 @@ import type {
   CookwareFlag,
   CategorizedIngredients,
   AddedRecipe,
+  RecipeWithFactor,
+  RecipeWithServings,
   CategoryIngredient,
   Category,
   QuantityPart,
@@ -55,6 +57,8 @@ export {
   CookwareFlag,
   CategorizedIngredients,
   AddedRecipe,
+  RecipeWithFactor,
+  RecipeWithServings,
   CategoryIngredient,
   Category,
   Section,

src/types.ts

@@ -361,16 +361,33 @@ export interface CategorizedIngredients {
 }
 
 /**
- * Represents a recipe that has been added to a shopping list.
+ * Represents a recipe together with a scaling factor
  * @category Types
  */
-export interface AddedRecipe {
+export interface RecipeWithFactor {
   /** The recipe that was added. */
   recipe: Recipe;
-  /** The factor the recipe was scaled by. */
+  /** The factor the recipe is scaled by. */
   factor: number;
 }
 
+/**
+ * Represents a recipe together with a servings value for scaling
+ * @category Types
+ */
+export interface RecipeWithServings {
+  /** The recipe that was added. */
+  recipe: Recipe;
+  /** The servings the recipe is scaled to */
+  servings: number;
+}
+
+/**
+ * Represents a recipe that has been added to a shopping list.
+ * @category Types
+ */
+export type AddedRecipe = RecipeWithFactor | RecipeWithServings;
+
 /**
  * Represents an ingredient that has been added to a shopping list
  * @category Types