b/a/noioutil: add an analyzer prohibiting use of ioutil
The ioutil package is deprecated and a tree-wide migration was already
done. This analyzer ensures that there can be no users of this package
in the future.
Change-Id: Ica6cd01ce5cb919d6f236225deeaff70b8e2800b
Reviewed-on: https://review.monogon.dev/c/monogon/+/451
Reviewed-by: Sergiusz Bazanski <serge@monogon.tech>
diff --git a/build/analysis/noioutil/noioutil.go b/build/analysis/noioutil/noioutil.go
new file mode 100644
index 0000000..96286e3
--- /dev/null
+++ b/build/analysis/noioutil/noioutil.go
@@ -0,0 +1,58 @@
+// Package noioutil contains a Go analysis pass designed to prevent use of the
+// deprecated ioutil package for which a tree-wide migration was already done.
+package noioutil
+
+import (
+ "go/ast"
+ "strconv"
+ "strings"
+
+ "golang.org/x/tools/go/analysis"
+)
+
+var Analyzer = &analysis.Analyzer{
+ Name: "noioutil",
+ Doc: "noioutil checks for imports of the deprecated ioutil package",
+ Run: run,
+}
+
+func run(p *analysis.Pass) (interface{}, error) {
+ for _, file := range p.Files {
+ if isGeneratedFile(file) {
+ continue
+ }
+ for _, i := range file.Imports {
+ importPath, err := strconv.Unquote(i.Path.Value)
+ if err != nil {
+ continue
+ }
+ if importPath == "io/ioutil" {
+ p.Report(analysis.Diagnostic{
+ Pos: i.Path.ValuePos,
+ End: i.Path.End(),
+ Message: "File imports the deprecated io/ioutil package. See https://pkg.go.dev/io/ioutil for replacements.",
+ })
+ }
+ }
+ }
+
+ return nil, nil
+}
+
+const (
+ genPrefix = "// Code generated"
+ genSuffix = "DO NOT EDIT."
+)
+
+// isGeneratedFile returns true if the file is generated
+// according to https://golang.org/s/generatedcode.
+func isGeneratedFile(file *ast.File) bool {
+ for _, c := range file.Comments {
+ for _, t := range c.List {
+ if strings.HasPrefix(t.Text, genPrefix) && strings.HasSuffix(t.Text, genSuffix) {
+ return true
+ }
+ }
+ }
+ return false
+}