diff options
Diffstat (limited to 'src/mongo/gotools/vendor/src/github.com/jacobsa/oglematchers/less_than.go')
-rw-r--r-- | src/mongo/gotools/vendor/src/github.com/jacobsa/oglematchers/less_than.go | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/src/mongo/gotools/vendor/src/github.com/jacobsa/oglematchers/less_than.go b/src/mongo/gotools/vendor/src/github.com/jacobsa/oglematchers/less_than.go new file mode 100644 index 00000000000..8258e45d99d --- /dev/null +++ b/src/mongo/gotools/vendor/src/github.com/jacobsa/oglematchers/less_than.go @@ -0,0 +1,152 @@ +// Copyright 2011 Aaron Jacobs. All Rights Reserved. +// Author: aaronjjacobs@gmail.com (Aaron Jacobs) +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package oglematchers + +import ( + "errors" + "fmt" + "math" + "reflect" +) + +// LessThan returns a matcher that matches integer, floating point, or strings +// values v such that v < x. Comparison is not defined between numeric and +// string types, but is defined between all integer and floating point types. +// +// x must itself be an integer, floating point, or string type; otherwise, +// LessThan will panic. +func LessThan(x interface{}) Matcher { + v := reflect.ValueOf(x) + kind := v.Kind() + + switch { + case isInteger(v): + case isFloat(v): + case kind == reflect.String: + + default: + panic(fmt.Sprintf("LessThan: unexpected kind %v", kind)) + } + + return &lessThanMatcher{v} +} + +type lessThanMatcher struct { + limit reflect.Value +} + +func (m *lessThanMatcher) Description() string { + // Special case: make it clear that strings are strings. + if m.limit.Kind() == reflect.String { + return fmt.Sprintf("less than \"%s\"", m.limit.String()) + } + + return fmt.Sprintf("less than %v", m.limit.Interface()) +} + +func compareIntegers(v1, v2 reflect.Value) (err error) { + err = errors.New("") + + switch { + case isSignedInteger(v1) && isSignedInteger(v2): + if v1.Int() < v2.Int() { + err = nil + } + return + + case isSignedInteger(v1) && isUnsignedInteger(v2): + if v1.Int() < 0 || uint64(v1.Int()) < v2.Uint() { + err = nil + } + return + + case isUnsignedInteger(v1) && isSignedInteger(v2): + if v1.Uint() <= math.MaxInt64 && int64(v1.Uint()) < v2.Int() { + err = nil + } + return + + case isUnsignedInteger(v1) && isUnsignedInteger(v2): + if v1.Uint() < v2.Uint() { + err = nil + } + return + } + + panic(fmt.Sprintf("compareIntegers: %v %v", v1, v2)) +} + +func getFloat(v reflect.Value) float64 { + switch { + case isSignedInteger(v): + return float64(v.Int()) + + case isUnsignedInteger(v): + return float64(v.Uint()) + + case isFloat(v): + return v.Float() + } + + panic(fmt.Sprintf("getFloat: %v", v)) +} + +func (m *lessThanMatcher) Matches(c interface{}) (err error) { + v1 := reflect.ValueOf(c) + v2 := m.limit + + err = errors.New("") + + // Handle strings as a special case. + if v1.Kind() == reflect.String && v2.Kind() == reflect.String { + if v1.String() < v2.String() { + err = nil + } + return + } + + // If we get here, we require that we are dealing with integers or floats. + v1Legal := isInteger(v1) || isFloat(v1) + v2Legal := isInteger(v2) || isFloat(v2) + if !v1Legal || !v2Legal { + err = NewFatalError("which is not comparable") + return + } + + // Handle the various comparison cases. + switch { + // Both integers + case isInteger(v1) && isInteger(v2): + return compareIntegers(v1, v2) + + // At least one float32 + case v1.Kind() == reflect.Float32 || v2.Kind() == reflect.Float32: + if float32(getFloat(v1)) < float32(getFloat(v2)) { + err = nil + } + return + + // At least one float64 + case v1.Kind() == reflect.Float64 || v2.Kind() == reflect.Float64: + if getFloat(v1) < getFloat(v2) { + err = nil + } + return + } + + // We shouldn't get here. + panic(fmt.Sprintf("lessThanMatcher.Matches: Shouldn't get here: %v %v", v1, v2)) +} |