starting point

testdata/src/a/a.go

@@ -4,8 +4,6 @@ import "github.com/rs/zerolog/log"
 
 func f() {
 	// The pattern can be written in regular expression.
-	var gopher int // want "identifier is gopher"
-	print(gopher)  // want "identifier is gopher"
 	var err error
-	log.Error().Err(err) // want "missing Msg() or Send()"
+	log.Error().Err(err) // want "missing Msg call for zerolog log method"
 }

zerologlint.go

@@ -2,39 +2,66 @@ package zerologlint
 
 import (
 	"go/ast"
+	"go/types"
 
 	"golang.org/x/tools/go/analysis"
-	"golang.org/x/tools/go/analysis/passes/inspect"
-	"golang.org/x/tools/go/ast/inspector"
 )
 
-const doc = "zerologlint is ..."
-
-// Analyzer is ...
 var Analyzer = &analysis.Analyzer{
-	Name: "zerologlint",
-	Doc:  doc,
+	Name: "logmsg",
+	Doc:  "check that zerolog log methods have a final Msg call",
 	Run:  run,
-	Requires: []*analysis.Analyzer{
-		inspect.Analyzer,
-	},
 }
 
-func run(pass *analysis.Pass) (any, error) {
-	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
 
-	nodeFilter := []ast.Node{
-		(*ast.Ident)(nil),
+func run(pass *analysis.Pass) (interface{}, error) {
+	for _, f := range pass.Files {
+		if !hasZerologImport(f) {
+			continue
+		}
+		ast.Inspect(f, func(n ast.Node) bool {
+			switch n := n.(type) {
+			case *ast.CallExpr:
+				if isLogMethod(n.Fun, pass.TypesInfo) && !hasMsgCall(n.Args, pass.TypesInfo) {
+					pass.Reportf(n.Pos(), "missing Msg call for zerolog log method")
+				}
+			}
+			return true
+		})
 	}
+	return nil, nil
+}
 
-	inspect.Preorder(nodeFilter, func(n ast.Node) {
-		switch n := n.(type) {
-		case *ast.Ident:
-			if n.Name == "gopher" {
-				pass.Reportf(n.Pos(), "identifier is gopher")
+func hasZerologImport(f *ast.File) bool {
+	for _, imp := range f.Imports {
+		if imp.Path.Value == `"github.com/rs/zerolog/log"` {
+			return true
+		}
+	}
+	return false
+}
+
+func isLogMethod(expr ast.Expr, info *types.Info) bool {
+	if sel, ok := expr.(*ast.SelectorExpr); ok {
+		if id, ok := sel.X.(*ast.Ident); ok {
+			if obj := info.ObjectOf(id); obj != nil {
+				switch sel.Sel.Name {
+				case "Debug", "Info", "Warn", "Error", "Fatal", "Panic":
+					return true
+				}
 			}
 		}
-	})
+	}
+	return false
+}
 
-	return nil, nil
+func hasMsgCall(args []ast.Expr, info *types.Info) bool {
+	for _, arg := range args {
+		if call, ok := arg.(*ast.CallExpr); ok {
+			if sel, ok := call.Fun.(*ast.SelectorExpr); ok && sel.Sel.Name == "Msg" && len(call.Args) == 1 {
+				return true
+			}
+		}
+	}
+	return false
 }

zerologlint_test.go

@@ -8,6 +8,7 @@ import (
 	"golang.org/x/tools/go/analysis/analysistest"
 )
 
+
 // TestAnalyzer is a test for Analyzer.
 func TestAnalyzer(t *testing.T) {
 	testdata := testutil.WithModules(t, analysistest.TestData(), nil)