6a979fb40d
* update staticcheck Don't fork staticcheck: use the upstream version. Remove unneeded SSA loading. * Cache go/analysis facts Don't load unneeded packages for go/analysis. Repeated run of go/analysis linters now 10x faster (2s vs 20s on this repo) than before.
71 lines
1.9 KiB
Go
71 lines
1.9 KiB
Go
package sharedcheck
|
|
|
|
import (
|
|
"go/ast"
|
|
"go/types"
|
|
|
|
"golang.org/x/tools/go/analysis"
|
|
"honnef.co/go/tools/internal/passes/buildssa"
|
|
. "honnef.co/go/tools/lint/lintdsl"
|
|
"honnef.co/go/tools/ssa"
|
|
)
|
|
|
|
func CheckRangeStringRunes(pass *analysis.Pass) (interface{}, error) {
|
|
for _, ssafn := range pass.ResultOf[buildssa.Analyzer].(*buildssa.SSA).SrcFuncs {
|
|
fn := func(node ast.Node) bool {
|
|
rng, ok := node.(*ast.RangeStmt)
|
|
if !ok || !IsBlank(rng.Key) {
|
|
return true
|
|
}
|
|
|
|
v, _ := ssafn.ValueForExpr(rng.X)
|
|
|
|
// Check that we're converting from string to []rune
|
|
val, _ := v.(*ssa.Convert)
|
|
if val == nil {
|
|
return true
|
|
}
|
|
Tsrc, ok := val.X.Type().(*types.Basic)
|
|
if !ok || Tsrc.Kind() != types.String {
|
|
return true
|
|
}
|
|
Tdst, ok := val.Type().(*types.Slice)
|
|
if !ok {
|
|
return true
|
|
}
|
|
TdstElem, ok := Tdst.Elem().(*types.Basic)
|
|
if !ok || TdstElem.Kind() != types.Int32 {
|
|
return true
|
|
}
|
|
|
|
// Check that the result of the conversion is only used to
|
|
// range over
|
|
refs := val.Referrers()
|
|
if refs == nil {
|
|
return true
|
|
}
|
|
|
|
// Expect two refs: one for obtaining the length of the slice,
|
|
// one for accessing the elements
|
|
if len(FilterDebug(*refs)) != 2 {
|
|
// TODO(dh): right now, we check that only one place
|
|
// refers to our slice. This will miss cases such as
|
|
// ranging over the slice twice. Ideally, we'd ensure that
|
|
// the slice is only used for ranging over (without
|
|
// accessing the key), but that is harder to do because in
|
|
// SSA form, ranging over a slice looks like an ordinary
|
|
// loop with index increments and slice accesses. We'd
|
|
// have to look at the associated AST node to check that
|
|
// it's a range statement.
|
|
return true
|
|
}
|
|
|
|
pass.Reportf(rng.Pos(), "should range over string, not []rune(string)")
|
|
|
|
return true
|
|
}
|
|
Inspect(ssafn.Syntax(), fn)
|
|
}
|
|
return nil, nil
|
|
}
|