implement oppgaves for part 3

Co-authored-by: Mikael Solstad <[email protected]>

Author: karl-run

.prettierrc

@@ -0,0 +1,3 @@
+{
+  "printWidth": 100
+}

workshop/oppgaver/01-pure-functions/pure-functions.test.ts

@@ -10,7 +10,6 @@ import {
 import { Transaction } from "../../createMockData";
 
 import { convertCurrency, isCurrency, takeFirstN } from "./pure-functions";
-import { createFilterByMordi } from "../02-higher-order-functions/higher-order-functions";
 
 describe("OPPGAVE 1.1", () => {
   it("correctly converts from DKK to SEK", () => {

workshop/oppgaver/03-currying-partial-application/currying-partial-application.test.ts

@@ -4,7 +4,7 @@ import transactions from "../../data/transactions";
 import { EUR_TO_NOK } from "../constants";
 import { currencyFilter, toAmount } from "./__spoilers/dontopen";
 
-import { filterByCurrency } from "./currying-partial-application";
+import { dkkToSek, ninetyDkkInNok } from "./currying-partial-application";
 import * as CPA from "./currying-partial-application";
 
 describe("OPPGAVE 3.1", () => {
@@ -18,38 +18,26 @@ describe("OPPGAVE 3.1", () => {
       .slice(0, 5);
 
     expect(result).toEqual([
-      -176572.8336, -180234.66, -195101.136, -292522.99919999996,
-      -42670.547999999995,
+      -176572.8336, -180234.66, -195101.136, -292522.99919999996, -42670.547999999995,
     ]);
   });
 });
 
 describe("OPPGAVE 3.2", () => {
+  it("tell if transaction is the given currency", () => {
+    const isCurrency = CPA.isCurrencyCurried("NOK");
 
-});
-
-describe("TODO maybe use, maybe garb", () => {
-  it("filters out all transactions in NOK", () => {
-    expect(filterByCurrency("NOK", transactions)).toHaveLength(165);
-  });
-
-  it("filters out all transactions in SEK", () => {
-    expect(filterByCurrency("SEK", transactions)).toHaveLength(150);
-  });
-
-  it("filters out all transactions in DKK", () => {
-    expect(filterByCurrency("DKK", transactions)).toHaveLength(195);
-  });
-
-  it("filters out all transactions in EUR", () => {
-    expect(filterByCurrency("EUR", transactions)).toHaveLength(159);
+    expect(isCurrency(transactions[0])).toBe(true);
+    expect(isCurrency(transactions[1])).toBe(false);
   });
+});
 
-  it("filters out all transactions in USD", () => {
-    expect(filterByCurrency("USD", transactions)).toHaveLength(172);
+describe("OPPGAVE 3.3", () => {
+  it("convert from DKK to SEK", () => {
+    expect(dkkToSek(100)).toBe(154);
   });
 
-  it("filters out all transactions in GBP", () => {
-    expect(filterByCurrency("GBP", transactions)).toHaveLength(171);
+  it("should have the correct NOK", () => {
+    expect(Number(ninetyDkkInNok.toFixed(1))).toBe(151.3);
   });
 });

workshop/oppgaver/03-currying-partial-application/currying-partial-application.ts

@@ -7,25 +7,34 @@ Copilot sier:
 
 import { Transaction } from "../../createMockData";
 import { Currency } from "../constants";
+import * as ExchangeRates from "../constants";
 
 /**
  * OPPGAVE 3.1: Gjør om convertCurrency fra oppgave 1 til å være curried.
  */
-export const convertCurrency = (exchangeRate: number, amount: number) =>
-  exchangeRate * amount;
+export const convertCurrency = (exchangeRate: number) => (amount: number) => exchangeRate * amount;
 
 /**
  * OPPGAVE 3.2: Gjør om isCurrency fra oppgave 1 til å være curried.
  */
-
-// garb???
 export const isCurrencyCurried = (currency: Currency) => {
   return (transaction: Transaction) => transaction.currency === currency;
 };
 
-export const filterByCurrency = (
-  currency: Currency,
-  transactions: Transaction[]
-) => {
-  return transactions.filter(isCurrencyCurried(currency));
-};
+/**
+ * OPPGAVE 3.3: Bruk din curried versjon av convertCurrency fra oppgave 3.1 til
+ * å lage en funksjon som konverterer fra DKK til SEK.
+ *
+ * Hint: Du finner riktig konverteringsrate i ExchangeRates
+ */
+
+type FromCurrencyToCurrency = (currency: number) => number;
+export const dkkToSek: FromCurrencyToCurrency = convertCurrency(ExchangeRates.DKK_TO_SEK);
+export const sekToUsd: FromCurrencyToCurrency = convertCurrency(ExchangeRates.SEK_TO_USD);
+export const usdToGbp: FromCurrencyToCurrency = convertCurrency(ExchangeRates.USD_TO_GBP);
+export const gbpToEur: FromCurrencyToCurrency = convertCurrency(ExchangeRates.GBP_TO_EUR);
+export const eurToNok: FromCurrencyToCurrency = convertCurrency(ExchangeRates.EUR_TO_NOK);
+
+// skal de skrive dette selv?
+export const ninetyDkkInNok = eurToNok(gbpToEur(usdToGbp(sekToUsd(dkkToSek(100)))));
+// export const ninetyDkkInNok = undefined;