fix(cmd): reject Savings Plan hourly commitments that round to 0.00

cmd/savings_plan_purchase.go

@@ -16,6 +16,12 @@ import (
 // regions and are not supported for Savings Plan purchases.
 const spAPIRegion = "us-east-1"
 
+// spCommitmentFormat is how the library formats HourlyCommitment for the
+// CreateSavingsPlan call (savingsplans/client.go). A positive value that
+// formats as "0.00" would be sent as a zero commitment, so preconditions
+// reject it.
+const spCommitmentFormat = "%.2f"
+
 // savingsPlanRowKey identifies one Savings Plan purchase. Two rows with the
 // same key buy the same plan twice.
 func savingsPlanRowKey(rec common.Recommendation) string {
@@ -142,6 +148,9 @@ func validateSavingsPlanPreconditions(rec common.Recommendation) error {
 	if d.HourlyCommitment <= 0 {
 		return fmt.Errorf("%s recommendation has no positive hourly commitment (got %v)", rec.Service, d.HourlyCommitment)
 	}
+	if fmt.Sprintf(spCommitmentFormat, d.HourlyCommitment) == "0.00" {
+		return fmt.Errorf("%s recommendation's hourly commitment %v would be sent as 0.00; it must be at least 0.005", rec.Service, d.HourlyCommitment)
+	}
 	if rec.Service == common.ServiceSavingsPlansEC2Instance && d.Region == "" {
 		return fmt.Errorf("EC2 Instance Savings Plan needs a region to pick the offering")
 	}

cmd/savings_plan_purchase_test.go

@@ -286,6 +286,25 @@ func TestValidatePurchasePreconditions(t *testing.T) {
 	}
 }
 
+// TestValidatePurchasePreconditions_RejectsCommitmentThatRoundsToZero covers
+// issue #2163: the library sends the hourly commitment as "%.2f", so a positive
+// value below 0.005 would reach CreateSavingsPlan as "0.00".
+func TestValidatePurchasePreconditions_RejectsCommitmentThatRoundsToZero(t *testing.T) {
+	withCommitment := func(c float64) common.Recommendation {
+		rec := parserShapedSP()
+		rec.Details = &common.SavingsPlanDetails{PlanType: "Compute", HourlyCommitment: c}
+		return rec
+	}
+	for _, c := range []float64{0.001, 0.004, 0.00499} {
+		err := validatePurchasePreconditions(withCommitment(c), "", defaultTestAccount)
+		require.Error(t, err, "commitment %v rounds to 0.00 and must be rejected", c)
+		assert.Contains(t, err.Error(), "0.00", "commitment %v", c)
+	}
+	for _, c := range []float64{0.005, 0.01, 1.5} {
+		assert.NoError(t, validatePurchasePreconditions(withCommitment(c), "", defaultTestAccount), "commitment %v", c)
+	}
+}
+
 func TestPurchaseSingleRec_DryRunReportsPreconditionFailure(t *testing.T) {
 	cfg := Config{CallerAccountID: defaultTestAccount, AuditLog: filepath.Join(t.TempDir(), "audit.jsonl")}
 	broken := parserShapedSP()