diff --git a/decimal.go b/decimal.go index a37a230..dda01ad 100644 --- a/decimal.go +++ b/decimal.go @@ -1292,6 +1292,16 @@ func abs(n int32) int32 { return n } +func (d Decimal) Format(f fmt.State, verb rune) { + switch verb { + case 'f': + places, _ := f.Precision() + fmt.Fprintf(f, d.StringFixed(int32(places))) + case 's': + fmt.Fprintf(f, d.String()) + } +} + // Cmp compares the numbers represented by d and d2 and returns: // // -1 if d < d2 diff --git a/decimal_test.go b/decimal_test.go index d398f2d..b1fd577 100644 --- a/decimal_test.go +++ b/decimal_test.go @@ -1261,6 +1261,67 @@ func TestDecimal_RoundCeilAndStringFixed(t *testing.T) { } } +func TestDecimal_Format(t *testing.T) { + type testData struct { + input string + places int32 + expected string + } + tests := []testData{ + {"1.454", 0, "1"}, + {"1.454", 1, "1.5"}, + {"1.454", 2, "1.45"}, + {"1.454", 3, "1.454"}, + {"1.454", 4, "1.4540"}, + {"1.454", 5, "1.45400"}, + {"0.454", 0, "0"}, + {"0.454", 1, "0.5"}, + {"0.454", 2, "0.45"}, + {"0.454", 3, "0.454"}, + {"0.454", 4, "0.4540"}, + {"0.454", 5, "0.45400"}, + {"0", 0, "0"}, + {"0", 1, "0.0"}, + {"0", 2, "0.00"}, + {"5", 2, "5.00"}, + {"5", 1, "5.0"}, + {"5", 0, "5"}, + {"500", 2, "500.00"}, + {"1.1001", 2, "1.10"}, + {"-1.1001", 2, "-1.10"}, + {"-1.454", 0, "-1"}, + {"-1.454", 1, "-1.5"}, + {"-1.454", 2, "-1.45"}, + {"-1.454", 3, "-1.454"}, + {"-1.454", 4, "-1.4540"}, + {"-1.454", 5, "-1.45400"}, + {"-1.554", 0, "-2"}, + {"-1.554", 1, "-1.6"}, + {"-1.554", 2, "-1.55"}, + {"-0.554", 0, "-1"}, + {"-0.454", 0, "0"}, + {"-0.454", 5, "-0.45400"}, + {"-500", 2, "-500.00"}, + } + + for _, test := range tests { + d, err := NewFromString(test.input) + if err != nil { + t.Fatal(err) + } + _, err = NewFromString(test.expected) + if err != nil { + t.Fatal(err) + } + formatIndicator := "%." + fmt.Sprintf("%d", test.places) + "f" + got := fmt.Sprintf(formatIndicator, d) + if got != test.expected { + t.Errorf("format indicator: %s: got %s, expected %s", + formatIndicator, got, test.expected) + } + } +} + func TestDecimal_RoundFloorAndStringFixed(t *testing.T) { type testData struct { input string