fix: spend is positive when more was spent then taken in

Author: morremeyer

pkg/controllers/budget.go

@@ -575,7 +575,7 @@ func SetAllocationsMonth(c *gin.Context) {
 		// If the mode is the spend of last month, calculate and set it
 		amount := allocation.Amount
 		if data.Mode == AllocateLastMonthSpend {
-			amount = models.Envelope{Model: models.Model{ID: allocation.EnvelopeID}}.Spent(pastMonth).Neg()
+			amount = models.Envelope{Model: models.Model{ID: allocation.EnvelopeID}}.Spent(pastMonth)
 		}
 
 		err = database.DB.Create(&models.Allocation{

pkg/controllers/budget_test.go

@@ -288,7 +288,7 @@ func (suite *TestSuiteEnv) TestBudgetMonth() {
 						{
 							Name:       "Utilities",
 							Month:      time.Date(2022, 1, 1, 0, 0, 0, 0, time.UTC),
-							Spent:      decimal.NewFromFloat(-10),
+							Spent:      decimal.NewFromFloat(10),
 							Balance:    decimal.NewFromFloat(10.99),
 							Allocation: decimal.NewFromFloat(20.99),
 						},
@@ -306,8 +306,8 @@ func (suite *TestSuiteEnv) TestBudgetMonth() {
 						{
 							Name:       "Utilities",
 							Month:      time.Date(2022, 2, 1, 0, 0, 0, 0, time.UTC),
-							Spent:      decimal.NewFromFloat(-5),
 							Balance:    decimal.NewFromFloat(53.11),
+							Spent:      decimal.NewFromFloat(5),
 							Allocation: decimal.NewFromFloat(47.12),
 						},
 					},
@@ -324,8 +324,8 @@ func (suite *TestSuiteEnv) TestBudgetMonth() {
 						{
 							Name:       "Utilities",
 							Month:      time.Date(2022, 3, 1, 0, 0, 0, 0, time.UTC),
-							Spent:      decimal.NewFromFloat(-15),
 							Balance:    decimal.NewFromFloat(69.28),
+							Spent:      decimal.NewFromFloat(15),
 							Allocation: decimal.NewFromFloat(31.17),
 						},
 					},

pkg/controllers/envelope_test.go

@@ -274,7 +274,7 @@ func (suite *TestSuiteEnv) TestEnvelopeMonth() {
 			models.EnvelopeMonth{
 				Name:       "Utilities",
 				Month:      time.Date(2022, 1, 1, 0, 0, 0, 0, time.UTC),
-				Spent:      decimal.NewFromFloat(-10),
+				Spent:      decimal.NewFromFloat(10),
 				Balance:    decimal.NewFromFloat(10.99),
 				Allocation: decimal.NewFromFloat(20.99),
 			},
@@ -284,8 +284,8 @@ func (suite *TestSuiteEnv) TestEnvelopeMonth() {
 			models.EnvelopeMonth{
 				Name:       "Utilities",
 				Month:      time.Date(2022, 2, 1, 0, 0, 0, 0, time.UTC),
-				Spent:      decimal.NewFromFloat(-5),
 				Balance:    decimal.NewFromFloat(53.11),
+				Spent:      decimal.NewFromFloat(5),
 				Allocation: decimal.NewFromFloat(47.12),
 			},
 		},
@@ -294,8 +294,8 @@ func (suite *TestSuiteEnv) TestEnvelopeMonth() {
 			models.EnvelopeMonth{
 				Name:       "Utilities",
 				Month:      time.Date(2022, 3, 1, 0, 0, 0, 0, time.UTC),
-				Spent:      decimal.NewFromFloat(-15),
 				Balance:    decimal.NewFromFloat(69.28),
+				Spent:      decimal.NewFromFloat(15),
 				Allocation: decimal.NewFromFloat(31.17),
 			},
 		},

pkg/models/envelope.go

@@ -62,7 +62,7 @@ func (e Envelope) Spent(t time.Time) decimal.Decimal {
 		}
 	}
 
-	return incomingSum.Sub(outgoingSum)
+	return outgoingSum.Sub(incomingSum)
 }
 
 // Balance calculates the balance of an Envelope in a specific month

pkg/models/envelope_test.go

@@ -95,11 +95,11 @@ func (suite *TestSuiteEnv) TestEnvelopeMonthSum() {
 
 	envelopeMonth, err := envelope.Month(january)
 	assert.Nil(suite.T(), err)
-	assert.True(suite.T(), envelopeMonth.Spent.Equal(spent.Neg()), "Month calculation for 2022-01 is wrong: should be %v, but is %v", spent.Neg(), envelopeMonth.Spent)
+	assert.True(suite.T(), envelopeMonth.Spent.Equal(spent), "Month calculation for 2022-01 is wrong: should be %v, but is %v", spent, envelopeMonth.Spent)
 
 	envelopeMonth, err = envelope.Month(january.AddDate(0, 1, 0))
 	assert.Nil(suite.T(), err)
-	assert.True(suite.T(), envelopeMonth.Spent.Equal(spent.Neg()), "Month calculation for 2022-02 is wrong: should be %v, but is %v", spent, envelopeMonth.Spent)
+	assert.True(suite.T(), envelopeMonth.Spent.Equal(spent), "Month calculation for 2022-02 is wrong: should be %v, but is %v", spent, envelopeMonth.Spent)
 
 	err = database.DB.Delete(&transaction).Error
 	if err != nil {
@@ -216,6 +216,18 @@ func (suite *TestSuiteEnv) TestEnvelopeMonthBalance() {
 		suite.Assert().Fail("Resource could not be saved", err)
 	}
 
+	// Used to test the Envelope.Balance method without any transactions
+	envelope2 := &models.Envelope{
+		EnvelopeCreate: models.EnvelopeCreate{
+			Name:       "Testing envelope without any transactions",
+			CategoryID: category.ID,
+		},
+	}
+	err = database.DB.Create(&envelope2).Error
+	if err != nil {
+		suite.Assert().Fail("Resource could not be saved", err)
+	}
+
 	january := time.Date(2022, 1, 1, 0, 0, 0, 0, time.UTC)
 
 	allocationJan := &models.Allocation{
@@ -281,4 +293,9 @@ func (suite *TestSuiteEnv) TestEnvelopeMonthBalance() {
 	envelopeMonth, err = envelope.Month(january.AddDate(0, 1, 0))
 	assert.Nil(suite.T(), err)
 	assert.True(suite.T(), envelopeMonth.Balance.Equal(shouldBalance), "Balance calculation for 2022-02 is wrong: should be %v, but is %v", shouldBalance, envelopeMonth.Balance)
+
+	shouldBalance = decimal.NewFromFloat(0)
+	envelopeMonth, err = envelope2.Month(january.AddDate(0, 1, 0))
+	assert.Nil(suite.T(), err)
+	assert.True(suite.T(), envelopeMonth.Balance.Equal(shouldBalance), "Balance calculation for 2022-02 is wrong: should be %v, but is %v", shouldBalance, envelopeMonth.Balance)
 }