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// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This file contains tests for the bool checker.
package testdata
import "io"
type T int
func (t T) Foo() int { return int(t) }
type FT func() int
var S []int
func RatherStupidConditions() {
var f, g func() int
if f() == 0 || f() == 0 { // OK f might have side effects
}
var t T
_ = t.Foo() == 2 || t.Foo() == 2 // OK Foo might have side effects
if v, w := f(), g(); v == w || v == w { // ERROR "redundant or: v == w || v == w"
}
_ = f == nil || f == nil // ERROR "redundant or: f == nil || f == nil"
_ = i == byte(1) || i == byte(1) // ERROR "redundant or: i == byte(1) || i == byte(1)"
_ = i == T(2) || i == T(2) // ERROR "redundant or: i == T(2) || i == T(2)"
_ = FT(f) == nil || FT(f) == nil // ERROR "redundant or: FT(f) == nil || FT(f) == nil"
_ = (func() int)(f) == nil || (func() int)(f) == nil // ERROR "redundant or: (func() int)(f) == nil || (func() int)(f) == nil"
_ = append(S, 3) == nil || append(S, 3) == nil // OK append has side effects
var namedFuncVar FT
_ = namedFuncVar() == namedFuncVar() // OK still func calls
var c chan int
_ = 0 == <-c || 0 == <-c // OK subsequent receives may yield different values
for i, j := <-c, <-c; i == j || i == j; i, j = <-c, <-c { // ERROR "redundant or: i == j || i == j"
}
var i, j, k int
_ = i+1 == 1 || i+1 == 1 // ERROR "redundant or: i\+1 == 1 || i\+1 == 1"
_ = i == 1 || j+1 == i || i == 1 // ERROR "redundant or: i == 1 || i == 1"
_ = i == 1 || i == 1 || f() == 1 // ERROR "redundant or: i == 1 || i == 1"
_ = i == 1 || f() == 1 || i == 1 // OK f may alter i as a side effect
_ = f() == 1 || i == 1 || i == 1 // ERROR "redundant or: i == 1 || i == 1"
// Test partition edge cases
_ = f() == 1 || i == 1 || i == 1 || j == 1 // ERROR "redundant or: i == 1 || i == 1"
_ = f() == 1 || j == 1 || i == 1 || i == 1 // ERROR "redundant or: i == 1 || i == 1"
_ = i == 1 || f() == 1 || i == 1 || i == 1 // ERROR "redundant or: i == 1 || i == 1"
_ = i == 1 || i == 1 || f() == 1 || i == 1 // ERROR "redundant or: i == 1 || i == 1"
_ = i == 1 || i == 1 || j == 1 || f() == 1 // ERROR "redundant or: i == 1 || i == 1"
_ = j == 1 || i == 1 || i == 1 || f() == 1 // ERROR "redundant or: i == 1 || i == 1"
_ = i == 1 || f() == 1 || f() == 1 || i == 1
_ = i == 1 || (i == 1 || i == 2) // ERROR "redundant or: i == 1 || i == 1"
_ = i == 1 || (f() == 1 || i == 1) // OK f may alter i as a side effect
_ = i == 1 || (i == 1 || f() == 1) // ERROR "redundant or: i == 1 || i == 1"
_ = i == 1 || (i == 2 || (i == 1 || i == 3)) // ERROR "redundant or: i == 1 || i == 1"
var a, b bool
_ = i == 1 || (a || (i == 1 || b)) // ERROR "redundant or: i == 1 || i == 1"
// Check that all redundant ors are flagged
_ = j == 0 ||
i == 1 ||
f() == 1 ||
j == 0 || // ERROR "redundant or: j == 0 || j == 0"
i == 1 || // ERROR "redundant or: i == 1 || i == 1"
i == 1 || // ERROR "redundant or: i == 1 || i == 1"
i == 1 ||
j == 0 ||
k == 0
_ = i == 1*2*3 || i == 1*2*3 // ERROR "redundant or: i == 1\*2\*3 || i == 1\*2\*3"
// These test that redundant, suspect expressions do not trigger multiple errors.
_ = i != 0 || i != 0 // ERROR "redundant or: i != 0 || i != 0"
_ = i == 0 && i == 0 // ERROR "redundant and: i == 0 && i == 0"
// and is dual to or; check the basics and
// let the or tests pull the rest of the weight.
_ = 0 != <-c && 0 != <-c // OK subsequent receives may yield different values
_ = f() != 0 && f() != 0 // OK f might have side effects
_ = f != nil && f != nil // ERROR "redundant and: f != nil && f != nil"
_ = i != 1 && i != 1 && f() != 1 // ERROR "redundant and: i != 1 && i != 1"
_ = i != 1 && f() != 1 && i != 1 // OK f may alter i as a side effect
_ = f() != 1 && i != 1 && i != 1 // ERROR "redundant and: i != 1 && i != 1"
}
func RoyallySuspectConditions() {
var i, j int
_ = i == 0 || i == 1 // OK
_ = i != 0 || i != 1 // ERROR "suspect or: i != 0 || i != 1"
_ = i != 0 || 1 != i // ERROR "suspect or: i != 0 || 1 != i"
_ = 0 != i || 1 != i // ERROR "suspect or: 0 != i || 1 != i"
_ = 0 != i || i != 1 // ERROR "suspect or: 0 != i || i != 1"
_ = (0 != i) || i != 1 // ERROR "suspect or: 0 != i || i != 1"
_ = i+3 != 7 || j+5 == 0 || i+3 != 9 // ERROR "suspect or: i\+3 != 7 || i\+3 != 9"
_ = i != 0 || j == 0 || i != 1 // ERROR "suspect or: i != 0 || i != 1"
_ = i != 0 || i != 1<<4 // ERROR "suspect or: i != 0 || i != 1<<4"
_ = i != 0 || j != 0
_ = 0 != i || 0 != j
var s string
_ = s != "one" || s != "the other" // ERROR "suspect or: s != .one. || s != .the other."
_ = "et" != "alii" || "et" != "cetera" // ERROR "suspect or: .et. != .alii. || .et. != .cetera."
_ = "me gustas" != "tu" || "le gustas" != "tu" // OK we could catch this case, but it's not worth the code
var err error
_ = err != nil || err != io.EOF // TODO catch this case?
// Sanity check and.
_ = i != 0 && i != 1 // OK
_ = i == 0 && i == 1 // ERROR "suspect and: i == 0 && i == 1"
_ = i == 0 && 1 == i // ERROR "suspect and: i == 0 && 1 == i"
_ = 0 == i && 1 == i // ERROR "suspect and: 0 == i && 1 == i"
_ = 0 == i && i == 1 // ERROR "suspect and: 0 == i && i == 1"
}
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