Support minor currencies

internal/cli/cli.go

@@ -60,6 +60,10 @@ func Validate(config *c.Config, options *Options, prevErr *error) func(*cobra.Co
 			return errors.New("invalid config: No watchlist provided") //nolint:goerr113
 		}
 
+		if len(config.Currency) > 0 && (strings.ToUpper(config.Currency) != config.Currency || len(config.Currency) != 3) {
+			return errors.New("invalid config: Display currency may only be an ISO 4217 major currency or blank (eg GBP not GBp; default: USD)") //nolint:goerr113
+		}
+
 		return nil
 	}
 }

internal/cli/cli_test.go

@@ -610,5 +610,62 @@ var _ = Describe("Cli", func() {
 			})
 		})
 
+		Describe("currency", func() {
+			When("a mixed-case currency is specified in the config file", func() {
+				It("should return an error (even if a valid minor currency)", func() {
+					options.Watchlist = "SEIT.L"
+					config = c.Config{
+						Currency: "USd",
+					}
+					outputErr := Validate(&config, &options, nil)(&cobra.Command{}, []string{})
+					Expect(outputErr).To(MatchError("invalid config: Display currency may only be an ISO 4217 major currency or blank (eg GBP not GBp; default: USD)"))
+				})
+			})
+
+			When("a blank currency is specified in the config file", func() {
+				It("should not return an error", func() {
+					options.Watchlist = "SEIT.L"
+					config := c.Config{
+						Currency: "",
+					}
+					outputErr := Validate(&config, &options, nil)(&cobra.Command{}, []string{})
+					Expect(outputErr).NotTo(HaveOccurred())
+				})
+			})
+
+			When("a short currency (len < 3) is specified in the config file", func() {
+				It("should return an error", func() {
+					options.Watchlist = "SEIT.L"
+					config := c.Config{
+						Currency: "US",
+					}
+					outputErr := Validate(&config, &options, nil)(&cobra.Command{}, []string{})
+					Expect(outputErr).To(MatchError("invalid config: Display currency may only be an ISO 4217 major currency or blank (eg GBP not GBp; default: USD)"))
+				})
+			})
+
+			When("a long currency (len > 3) is specified in the config file", func() {
+				It("should return an error", func() {
+					options.Watchlist = "SEIT.L"
+					config := c.Config{
+						Currency: "USD2",
+					}
+					outputErr := Validate(&config, &options, nil)(&cobra.Command{}, []string{})
+					Expect(outputErr).To(MatchError("invalid config: Display currency may only be an ISO 4217 major currency or blank (eg GBP not GBp; default: USD)"))
+				})
+			})
+
+			PWhen("a non-ISO 4217 currency is specified in the config file", func() {
+				PIt("should return an error", func() {
+					options.Watchlist = "SEIT.L"
+					config = c.Config{
+						Currency: "XXX",
+					}
+					outputErr := Validate(&config, &options, nil)(&cobra.Command{}, []string{})
+					Expect(outputErr).To(MatchError("invalid config: Display currency may only be an ISO 4217 major currency or blank (eg GBP not GBp; default: USD)"))
+				})
+			})
+		})
+
 	})
 })

internal/monitor/yahoo/monitor-currency-rates/monitor_currency_rates_test.go

@@ -1,6 +1,7 @@
 package monitorCurrencyRate_test
 
 import (
+	"math"
 	"net/http"
 	"time"
 
@@ -18,8 +19,9 @@ import (
 var _ = Describe("MonitorCurrencyRates", func() {
 
 	var (
-		server *ghttp.Server
-		client *unary.UnaryAPI
+		server                   *ghttp.Server
+		client                   *unary.UnaryAPI
+		float64EqualityTolerance = 1e-9
 	)
 
 	BeforeEach(func() {
@@ -81,7 +83,7 @@ var _ = Describe("MonitorCurrencyRates", func() {
 
 			When("a request for currency rates is received", func() {
 
-				It("should return currency rates requested and all previous currency rates", func() {
+				It("should return currency rates requested, and minor units, and all previous currency rates", func() {
 					// Setup server to respond to EURUSD=X
 					server.RouteToHandler("GET", "/v7/finance/quote",
 						ghttp.CombineHandlers(
@@ -115,6 +117,11 @@ var _ = Describe("MonitorCurrencyRates", func() {
 					Expect(rates["EUR"].ToCurrency).To(Equal("USD"))
 					Expect(rates["EUR"].Rate).To(Equal(1.1))
 
+					Expect(rates).To(HaveKey("EUr"))
+					Expect(rates["EUr"].FromCurrency).To(Equal("EUr"))
+					Expect(rates["EUr"].ToCurrency).To(Equal("USD"))
+					Expect(float64ValuesAreEqual(rates["EUr"].Rate, 0.011, float64EqualityTolerance)).To(BeTrue())
+
 					// Replace API to only return quotes for GBPUSD=X
 					server.RouteToHandler("GET", "/v7/finance/quote",
 						ghttp.CombineHandlers(
@@ -141,6 +148,47 @@ var _ = Describe("MonitorCurrencyRates", func() {
 					Expect(rates).To(HaveKey("GBP"))
 					Expect(rates["EUR"].Rate).To(Equal(1.1))
 					Expect(rates["GBP"].Rate).To(Equal(1.3))
+
+					Expect(rates).To(HaveKey("EUr"))
+					Expect(rates).To(HaveKey("GBp"))
+					Expect(float64ValuesAreEqual(rates["EUr"].Rate, 0.011, float64EqualityTolerance)).To(BeTrue())
+					Expect(float64ValuesAreEqual(rates["GBp"].Rate, 0.013, float64EqualityTolerance)).To(BeTrue())
+
+					// Replace API to only return quotes for JPNUSD=X (no minor currency)
+					server.RouteToHandler("GET", "/v7/finance/quote",
+						ghttp.CombineHandlers(
+							verifyRequest(server, "GET", "/v7/finance/quote", "symbols", "JPYUSD=X"),
+							ghttp.RespondWithJSONEncoded(http.StatusOK, unary.Response{
+								QuoteResponse: unary.ResponseQuoteResponse{
+									Quotes: []unary.ResponseQuote{{
+										Symbol:             "JPYUSD=X",
+										RegularMarketPrice: unary.ResponseFieldFloat{Raw: 0.0068, Fmt: "0.0068"},
+										Currency:           "USD",
+									}},
+									Error: nil,
+								},
+							}),
+						),
+					)
+
+					// Request EUR, GBP & JPY
+					requestCh <- []string{"EUR", "GBP", "JPY"}
+
+					Eventually(updateCh, 500*time.Millisecond).Should(Receive(&rates))
+
+					Expect(rates).To(HaveKey("EUR"))
+					Expect(rates).To(HaveKey("GBP"))
+					Expect(rates).To(HaveKey("JPY"))
+					Expect(rates["EUR"].Rate).To(Equal(1.1))
+					Expect(rates["GBP"].Rate).To(Equal(1.3))
+					Expect(rates["JPY"].Rate).To(Equal(0.0068))
+
+					Expect(rates).To(HaveKey("EUr"))
+					Expect(rates).To(HaveKey("GBp"))
+					Expect(rates).NotTo(HaveKey("JPy"))
+					Expect(float64ValuesAreEqual(rates["EUr"].Rate, 0.011, float64EqualityTolerance)).To(BeTrue())
+					Expect(float64ValuesAreEqual(rates["GBp"].Rate, 0.013, float64EqualityTolerance)).To(BeTrue())
+
 				})
 
 				When("the currency request is empty", func() {
@@ -380,6 +428,10 @@ var _ = Describe("MonitorCurrencyRates", func() {
 
 })
 
+func float64ValuesAreEqual(f1 float64, f2 float64, tolerance float64) bool {
+	return math.Abs(f1-f2) < tolerance
+}
+
 func verifyRequest(server *ghttp.Server, method, path string, queryKey, queryValue string) func(w http.ResponseWriter, r *http.Request) {
 	return func(w http.ResponseWriter, r *http.Request) {
 		Expect(r.Method).To(Equal(method))

internal/monitor/yahoo/unary/helpers-currency.go

@@ -0,0 +1,191 @@
+package unary
+
+// minorCurrency represents the scaling ('minor unit') for a minor currency.
+// Convert major to minor by multiplying by 10^n and minor to major by dividing by 10^n.
+type minorCurrency struct {
+	MajorCurrencyCode string
+	MinorCurrencyCode string
+	MinorUnit         float64
+}
+
+// Just consider the currencies traded on major exchanges
+func MinorUnitForCurrencyCode(majorCurrency string) (bool, string, float64) {
+
+	var minorCurrencyCodeByMajorCurrencyCode = map[string]minorCurrency{
+		"AUD": {"AUD", "AUd", 2},
+		"CAD": {"CAD", "CAd", 2},
+		"CHF": {"CHF", "CHf", 2},
+		"CNY": {"CNY", "CNy", 2},
+		"EUR": {"EUR", "EUr", 2},
+		"GBP": {"GBP", "GBp", 2},
+		"HKD": {"HKD", "HKd", 2},
+		"INR": {"INR", "INr", 2},
+		"TWD": {"TWD", "TWd", 2},
+		"USD": {"USD", "USd", 2},
+		"ZAR": {"ZAR", "ZAr", 2},
+	}
+
+	if mc, ok := minorCurrencyCodeByMajorCurrencyCode[majorCurrency]; ok {
+
+		return true, mc.MinorCurrencyCode, mc.MinorUnit
+	}
+
+	return false, "", 0
+
+}
+
+/*
+// This map is derived from https://www.six-group.com/dam/download/financial-information/data-center/iso-currrency/lists/list-one.xls
+// Retaining this as a reference to the complete list as at October 2025.
+var _minorCurrencyCodeByMajorCurrencyCode = map[string]minorCurrency{
+	"AED": {"AED", "AEd", 2},
+	"AFN": {"AFN", "AFn", 2},
+	"ALL": {"ALL", "ALl", 2},
+	"AMD": {"AMD", "AMd", 2},
+	"AOA": {"AOA", "AOa", 2},
+	"ARS": {"ARS", "ARs", 2},
+	"AUD": {"AUD", "AUd", 2},
+	"AWG": {"AWG", "AWg", 2},
+	"AZN": {"AZN", "AZn", 2},
+	"BAM": {"BAM", "BAm", 2},
+	"BBD": {"BBD", "BBd", 2},
+	"BDT": {"BDT", "BDt", 2},
+	"BGN": {"BGN", "BGn", 2},
+	"BHD": {"BHD", "BHd", 3},
+	"BMD": {"BMD", "BMd", 2},
+	"BND": {"BND", "BNd", 2},
+	"BOB": {"BOB", "BOb", 2},
+	"BOV": {"BOV", "BOv", 2},
+	"BRL": {"BRL", "BRl", 2},
+	"BSD": {"BSD", "BSd", 2},
+	"BTN": {"BTN", "BTn", 2},
+	"BWP": {"BWP", "BWp", 2},
+	"BYN": {"BYN", "BYn", 2},
+	"BZD": {"BZD", "BZd", 2},
+	"CAD": {"CAD", "CAd", 2},
+	"CDF": {"CDF", "CDf", 2},
+	"CHE": {"CHE", "CHe", 2},
+	"CHF": {"CHF", "CHf", 2},
+	"CHW": {"CHW", "CHw", 2},
+	"CLF": {"CLF", "CLf", 4},
+	"CNY": {"CNY", "CNy", 2},
+	"COP": {"COP", "COp", 2},
+	"COU": {"COU", "COu", 2},
+	"CRC": {"CRC", "CRc", 2},
+	"CUP": {"CUP", "CUp", 2},
+	"CVE": {"CVE", "CVe", 2},
+	"CZK": {"CZK", "CZk", 2},
+	"DKK": {"DKK", "DKk", 2},
+	"DOP": {"DOP", "DOp", 2},
+	"DZD": {"DZD", "DZd", 2},
+	"EGP": {"EGP", "EGp", 2},
+	"ERN": {"ERN", "ERn", 2},
+	"ETB": {"ETB", "ETb", 2},
+	"EUR": {"EUR", "EUr", 2},
+	"FJD": {"FJD", "FJd", 2},
+	"FKP": {"FKP", "FKp", 2},
+	"GBP": {"GBP", "GBp", 2},
+	"GEL": {"GEL", "GEl", 2},
+	"GHS": {"GHS", "GHs", 2},
+	"GIP": {"GIP", "GIp", 2},
+	"GMD": {"GMD", "GMd", 2},
+	"GTQ": {"GTQ", "GTq", 2},
+	"GYD": {"GYD", "GYd", 2},
+	"HKD": {"HKD", "HKd", 2},
+	"HNL": {"HNL", "HNl", 2},
+	"HTG": {"HTG", "HTg", 2},
+	"HUF": {"HUF", "HUf", 2},
+	"IDR": {"IDR", "IDr", 2},
+	"ILS": {"ILS", "ILs", 2},
+	"INR": {"INR", "INr", 2},
+	"IQD": {"IQD", "IQd", 3},
+	"IRR": {"IRR", "IRr", 2},
+	"JMD": {"JMD", "JMd", 2},
+	"JOD": {"JOD", "JOd", 3},
+	"KES": {"KES", "KEs", 2},
+	"KGS": {"KGS", "KGs", 2},
+	"KHR": {"KHR", "KHr", 2},
+	"KPW": {"KPW", "KPw", 2},
+	"KWD": {"KWD", "KWd", 3},
+	"KYD": {"KYD", "KYd", 2},
+	"KZT": {"KZT", "KZt", 2},
+	"LAK": {"LAK", "LAk", 2},
+	"LBP": {"LBP", "LBp", 2},
+	"LKR": {"LKR", "LKr", 2},
+	"LRD": {"LRD", "LRd", 2},
+	"LSL": {"LSL", "LSl", 2},
+	"LYD": {"LYD", "LYd", 3},
+	"MAD": {"MAD", "MAd", 2},
+	"MDL": {"MDL", "MDl", 2},
+	"MGA": {"MGA", "MGa", 2},
+	"MKD": {"MKD", "MKd", 2},
+	"MMK": {"MMK", "MMk", 2},
+	"MNT": {"MNT", "MNt", 2},
+	"MOP": {"MOP", "MOp", 2},
+	"MRU": {"MRU", "MRu", 2},
+	"MUR": {"MUR", "MUr", 2},
+	"MVR": {"MVR", "MVr", 2},
+	"MWK": {"MWK", "MWk", 2},
+	"MXN": {"MXN", "MXn", 2},
+	"MXV": {"MXV", "MXv", 2},
+	"MYR": {"MYR", "MYr", 2},
+	"MZN": {"MZN", "MZn", 2},
+	"NAD": {"NAD", "NAd", 2},
+	"NGN": {"NGN", "NGn", 2},
+	"NIO": {"NIO", "NIo", 2},
+	"NOK": {"NOK", "NOk", 2},
+	"NPR": {"NPR", "NPr", 2},
+	"NZD": {"NZD", "NZd", 2},
+	"OMR": {"OMR", "OMr", 3},
+	"PAB": {"PAB", "PAb", 2},
+	"PEN": {"PEN", "PEn", 2},
+	"PGK": {"PGK", "PGk", 2},
+	"PHP": {"PHP", "PHp", 2},
+	"PKR": {"PKR", "PKr", 2},
+	"PLN": {"PLN", "PLn", 2},
+	"QAR": {"QAR", "QAr", 2},
+	"RON": {"RON", "ROn", 2},
+	"RSD": {"RSD", "RSd", 2},
+	"RUB": {"RUB", "RUb", 2},
+	"SAR": {"SAR", "SAr", 2},
+	"SBD": {"SBD", "SBd", 2},
+	"SCR": {"SCR", "SCr", 2},
+	"SDG": {"SDG", "SDg", 2},
+	"SEK": {"SEK", "SEk", 2},
+	"SGD": {"SGD", "SGd", 2},
+	"SHP": {"SHP", "SHp", 2},
+	"SLE": {"SLE", "SLe", 2},
+	"SOS": {"SOS", "SOs", 2},
+	"SRD": {"SRD", "SRd", 2},
+	"SSP": {"SSP", "SSp", 2},
+	"STN": {"STN", "STn", 2},
+	"SVC": {"SVC", "SVc", 2},
+	"SYP": {"SYP", "SYp", 2},
+	"SZL": {"SZL", "SZl", 2},
+	"THB": {"THB", "THb", 2},
+	"TJS": {"TJS", "TJs", 2},
+	"TMT": {"TMT", "TMt", 2},
+	"TND": {"TND", "TNd", 3},
+	"TOP": {"TOP", "TOp", 2},
+	"TRY": {"TRY", "TRy", 2},
+	"TTD": {"TTD", "TTd", 2},
+	"TWD": {"TWD", "TWd", 2},
+	"TZS": {"TZS", "TZs", 2},
+	"UAH": {"UAH", "UAh", 2},
+	"USD": {"USD", "USd", 2},
+	"USN": {"USN", "USn", 2},
+	"UYU": {"UYU", "UYu", 2},
+	"UYW": {"UYW", "UYw", 4},
+	"UZS": {"UZS", "UZs", 2},
+	"VED": {"VED", "VEd", 2},
+	"VES": {"VES", "VEs", 2},
+	"WST": {"WST", "WSt", 2},
+	"XAD": {"XAD", "XAd", 2},
+	"XCD": {"XCD", "XCd", 2},
+	"XCG": {"XCG", "XCg", 2},
+	"YER": {"YER", "YEr", 2},
+	"ZAR": {"ZAR", "ZAr", 2},
+	"ZMW": {"ZMW", "ZMw", 2},
+	"ZWG": {"ZWG", "ZWg", 2},
+}
+*/

internal/monitor/yahoo/unary/helpers-quote.go

@@ -1,8 +1,6 @@
 package unary
 
 import (
-	"strings"
-
 	c "github.com/achannarasappa/ticker/v5/internal/common"
 )
 
@@ -22,7 +20,7 @@ func transformResponseQuote(responseQuote ResponseQuote) c.AssetQuote {
 		Symbol: responseQuote.Symbol,
 		Class:  assetClass,
 		Currency: c.Currency{
-			FromCurrencyCode: strings.ToUpper(responseQuote.Currency),
+			FromCurrencyCode: responseQuote.Currency,
 		},
 		QuotePrice: c.QuotePrice{
 			Price:          responseQuote.RegularMarketPrice.Raw,