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|
// TODO: doc
package defererr
import (
"fmt"
"go/ast"
"golang.org/x/tools/go/analysis"
)
var Analyzer = &analysis.Analyzer{
Name: "defererr",
Doc: "reports issues returning errors from defer",
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
// TODO: Find defer closure
// Does it set error defined in outer scope?
// Does outer scope declare error variable in signature?
// Is err variable returned after closure?
for _, file := range pass.Files {
ast.Inspect(
file,
func(node ast.Node) bool {
deferStmt, ok := node.(*ast.DeferStmt)
if !ok {
return true
}
// Look for a function literal after the `defer` statement.
funcLit, ok := deferStmt.Call.Fun.(*ast.FuncLit)
if !ok {
return true
}
funcScope := pass.TypesInfo.Scopes[funcLit.Type]
// Try to find the function where the defer is defined. Note, defer can be defined in an inner block.
funcType, ok := funcScope.Parent().(*ast.FuncType)
if !ok {
return true
}
fmt.Printf("func: %#v\n", funcType)
if funcLit.Type.Results == nil {
return true
}
for _, returnVal := range funcLit.Type.Results.List {
fmt.Printf("returnVal: %#v\n", returnVal)
}
return true
},
)
}
return nil, nil
}
|
