Add staticcheck tool

vendor/honnef.co/go/tools/staticcheck/sa1004/sa1004.go

@@ -0,0 +1,72 @@
+package sa1004
+
+import (
+	"fmt"
+	"go/ast"
+	"go/constant"
+	"go/types"
+
+	"honnef.co/go/tools/analysis/code"
+	"honnef.co/go/tools/analysis/edit"
+	"honnef.co/go/tools/analysis/lint"
+	"honnef.co/go/tools/analysis/report"
+	"honnef.co/go/tools/pattern"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
+	Analyzer: &analysis.Analyzer{
+		Name:     "SA1004",
+		Run:      run,
+		Requires: code.RequiredAnalyzers,
+	},
+	Doc: &lint.RawDocumentation{
+		Title: `Suspiciously small untyped constant in \'time.Sleep\'`,
+		Text: `The \'time\'.Sleep function takes a \'time.Duration\' as its only argument.
+Durations are expressed in nanoseconds. Thus, calling \'time.Sleep(1)\'
+will sleep for 1 nanosecond. This is a common source of bugs, as sleep
+functions in other languages often accept seconds or milliseconds.
+
+The \'time\' package provides constants such as \'time.Second\' to express
+large durations. These can be combined with arithmetic to express
+arbitrary durations, for example \'5 * time.Second\' for 5 seconds.
+
+If you truly meant to sleep for a tiny amount of time, use
+\'n * time.Nanosecond\' to signal to Staticcheck that you did mean to sleep
+for some amount of nanoseconds.`,
+		Since:    "2017.1",
+		Severity: lint.SeverityWarning,
+		MergeIf:  lint.MergeIfAny,
+	},
+})
+
+var Analyzer = SCAnalyzer.Analyzer
+
+var (
+	checkTimeSleepConstantPatternQ   = pattern.MustParse(`(CallExpr (Symbol "time.Sleep") lit@(IntegerLiteral value))`)
+	checkTimeSleepConstantPatternRns = pattern.MustParse(`(BinaryExpr duration "*" (SelectorExpr (Ident "time") (Ident "Nanosecond")))`)
+	checkTimeSleepConstantPatternRs  = pattern.MustParse(`(BinaryExpr duration "*" (SelectorExpr (Ident "time") (Ident "Second")))`)
+)
+
+func run(pass *analysis.Pass) (any, error) {
+	for _, m := range code.Matches(pass, checkTimeSleepConstantPatternQ) {
+		n, ok := constant.Int64Val(m.State["value"].(types.TypeAndValue).Value)
+		if !ok {
+			continue
+		}
+		if n == 0 || n > 120 {
+			// time.Sleep(0) is a seldom used pattern in concurrency
+			// tests. >120 might be intentional. 120 was chosen
+			// because the user could've meant 2 minutes.
+			continue
+		}
+
+		lit := m.State["lit"].(ast.Node)
+		report.Report(pass, lit,
+			fmt.Sprintf("sleeping for %d nanoseconds is probably a bug; be explicit if it isn't", n), report.Fixes(
+				edit.Fix("Explicitly use nanoseconds", edit.ReplaceWithPattern(pass.Fset, lit, checkTimeSleepConstantPatternRns, pattern.State{"duration": lit})),
+				edit.Fix("Use seconds", edit.ReplaceWithPattern(pass.Fset, lit, checkTimeSleepConstantPatternRs, pattern.State{"duration": lit}))))
+	}
+	return nil, nil
+}