Sebastiaan van Stijn bf27481efd
update staticcheck to v2020.1.3
full diff: https://github.com/dominikh/go-tools/compare/2019.2.3...2020.1.3

Also updates tests to accomodate updated rules:

    --- FAIL: TestSourcesFromTestdataWithIssuesDir/staticcheck.go (0.43s)
            linters_test.go:137: [run --disable-all --print-issued-lines=false --print-linter-name=false --out-format=line-number --max-same-issues=10 -Estaticcheck --no-config testdata/staticcheck.go]
            linters_test.go:33:
                    Error Trace:    linters_test.go:33
                                                linters_test.go:138
                                                linters_test.go:53
                    Error:          Received unexpected error:

                                    staticcheck.go:11: no match for `self-assignment of x to x` vs ["SA4006: this value of `x` is never used"] in:
                                        staticcheck.go:11:2: SA4006: this value of `x` is never used
                                    unmatched errors
                                    staticcheck.go:11:2: SA4006: this value of `x` is never used
                    Test:           TestSourcesFromTestdataWithIssuesDir/staticcheck.go

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2020-03-10 14:55:19 +01:00

117 lines
2.9 KiB
Go

// Copyright 2013 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.
package ir
// lvalues are the union of addressable expressions and map-index
// expressions.
import (
"go/ast"
"go/types"
)
// An lvalue represents an assignable location that may appear on the
// left-hand side of an assignment. This is a generalization of a
// pointer to permit updates to elements of maps.
//
type lvalue interface {
store(fn *Function, v Value, source ast.Node) // stores v into the location
load(fn *Function, source ast.Node) Value // loads the contents of the location
address(fn *Function) Value // address of the location
typ() types.Type // returns the type of the location
}
// An address is an lvalue represented by a true pointer.
type address struct {
addr Value
expr ast.Expr // source syntax of the value (not address) [debug mode]
}
func (a *address) load(fn *Function, source ast.Node) Value {
return emitLoad(fn, a.addr, source)
}
func (a *address) store(fn *Function, v Value, source ast.Node) {
store := emitStore(fn, a.addr, v, source)
if a.expr != nil {
// store.Val is v, converted for assignability.
emitDebugRef(fn, a.expr, store.Val, false)
}
}
func (a *address) address(fn *Function) Value {
if a.expr != nil {
emitDebugRef(fn, a.expr, a.addr, true)
}
return a.addr
}
func (a *address) typ() types.Type {
return deref(a.addr.Type())
}
// An element is an lvalue represented by m[k], the location of an
// element of a map. These locations are not addressable
// since pointers cannot be formed from them, but they do support
// load() and store().
//
type element struct {
m, k Value // map
t types.Type // map element type
}
func (e *element) load(fn *Function, source ast.Node) Value {
l := &MapLookup{
X: e.m,
Index: e.k,
}
l.setType(e.t)
return fn.emit(l, source)
}
func (e *element) store(fn *Function, v Value, source ast.Node) {
up := &MapUpdate{
Map: e.m,
Key: e.k,
Value: emitConv(fn, v, e.t, source),
}
fn.emit(up, source)
}
func (e *element) address(fn *Function) Value {
panic("map elements are not addressable")
}
func (e *element) typ() types.Type {
return e.t
}
// A blank is a dummy variable whose name is "_".
// It is not reified: loads are illegal and stores are ignored.
//
type blank struct{}
func (bl blank) load(fn *Function, source ast.Node) Value {
panic("blank.load is illegal")
}
func (bl blank) store(fn *Function, v Value, source ast.Node) {
s := &BlankStore{
Val: v,
}
fn.emit(s, source)
}
func (bl blank) address(fn *Function) Value {
panic("blank var is not addressable")
}
func (bl blank) typ() types.Type {
// This should be the type of the blank Ident; the typechecker
// doesn't provide this yet, but fortunately, we don't need it
// yet either.
panic("blank.typ is unimplemented")
}