Add staticcheck tool

vendor/honnef.co/go/tools/stylecheck/st1001/st1001.go

@@ -0,0 +1,71 @@
+package st1001
+
+import (
+	"honnef.co/go/tools/analysis/code"
+	"honnef.co/go/tools/analysis/facts/generated"
+	"honnef.co/go/tools/analysis/lint"
+	"honnef.co/go/tools/analysis/report"
+	"honnef.co/go/tools/config"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
+	Analyzer: &analysis.Analyzer{
+		Name:     "ST1001",
+		Run:      run,
+		Requires: []*analysis.Analyzer{generated.Analyzer, config.Analyzer},
+	},
+	Doc: &lint.RawDocumentation{
+		Title: `Dot imports are discouraged`,
+		Text: `Dot imports that aren't in external test packages are discouraged.
+
+The \'dot_import_whitelist\' option can be used to whitelist certain
+imports.
+
+Quoting Go Code Review Comments:
+
+> The \'import .\' form can be useful in tests that, due to circular
+> dependencies, cannot be made part of the package being tested:
+> 
+>     package foo_test
+> 
+>     import (
+>         "bar/testutil" // also imports "foo"
+>         . "foo"
+>     )
+> 
+> In this case, the test file cannot be in package foo because it
+> uses \'bar/testutil\', which imports \'foo\'. So we use the \'import .\'
+> form to let the file pretend to be part of package foo even though
+> it is not. Except for this one case, do not use \'import .\' in your
+> programs. It makes the programs much harder to read because it is
+> unclear whether a name like \'Quux\' is a top-level identifier in the
+> current package or in an imported package.`,
+		Since:   "2019.1",
+		Options: []string{"dot_import_whitelist"},
+		MergeIf: lint.MergeIfAny,
+	},
+})
+
+var Analyzer = SCAnalyzer.Analyzer
+
+func run(pass *analysis.Pass) (any, error) {
+	for _, f := range pass.Files {
+	imports:
+		for _, imp := range f.Imports {
+			path := imp.Path.Value
+			path = path[1 : len(path)-1]
+			for _, w := range config.For(pass).DotImportWhitelist {
+				if w == path {
+					continue imports
+				}
+			}
+
+			if imp.Name != nil && imp.Name.Name == "." && !code.IsInTest(pass, f) {
+				report.Report(pass, imp, "should not use dot imports", report.FilterGenerated())
+			}
+		}
+	}
+	return nil, nil
+}