1 files changed, 104 insertions, 0 deletions
diff --git a/cmd/cvet/check_command.go b/cmd/cvet/check_command.go
new file mode 100644
index 0000000..47db8fa
--- /dev/null
+++ b/cmd/cvet/check_command.go
@@ -0,0 +1,104 @@
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"strings"
+
+	"github.com/samber/lo"
+	"golang.org/x/tools/go/analysis"
+)
+
+func isCommandFunc(node *ast.FuncDecl) bool {
+	return strings.HasSuffix(node.Name.Name, "Command")
+}
+
+func loggerCommandKeyValueArgFinder(pass *analysis.Pass, commandName string) func(arg ast.Expr) bool {
+	return func(arg ast.Expr) bool {
+		call, ok := arg.(*ast.CallExpr)
+		if !ok {
+			return false
+		}
+		firstArg, ok := call.Args[0].(*ast.BasicLit)
+		if !ok {
+			return false
+		}
+		if firstArg.Kind == token.STRING && firstArg.Value == `"command"` {
+			secondArg, ok := call.Args[1].(*ast.BasicLit)
+			if !ok {
+				pass.Reportf(arg.Pos(), "logger command name must be a literal")
+				return true
+			}
+			if secondArg.Kind != token.STRING {
+				pass.Reportf(arg.Pos(), "logger command name must be a string literal")
+				return true
+			}
+
+			value := secondArg.Value[1 : len(secondArg.Value)-1]
+			if value != commandName {
+				pass.Reportf(arg.Pos(), fmt.Sprintf("logger command name must be function name %s, but found %s", commandName, value))
+				return true
+			}
+			return true
+		}
+
+		return false
+	}
+}
+
+func checkStmtHaveNoRawSlog(pass *analysis.Pass, stmts []ast.Stmt) {
+	for _, stmt := range stmts[1:] {
+		switch stmt := stmt.(type) {
+		case *ast.ExprStmt:
+			if call, ok := stmt.X.(*ast.CallExpr); ok {
+				if selector, ok := call.Fun.(*ast.SelectorExpr); ok {
+					if isIdent(selector.X, "slog") {
+						pass.Reportf(stmt.Pos(), "logger must be used to log")
+					}
+				}
+			}
+		case *ast.IfStmt:
+			checkStmtHaveNoRawSlog(pass, stmt.Body.List)
+		}
+	}
+}
+
+func checkCommandLogger(pass *analysis.Pass, node *ast.FuncDecl) {
+	commandName := node.Name.Name
+	firstStmt, ok := node.Body.List[0].(*ast.AssignStmt)
+	if !ok || !isIdent(firstStmt.Lhs[0], "logger") {
+		pass.Reportf(node.Pos(), "command first statement must be a logger creation")
+		return
+	}
+
+	call, ok := firstStmt.Rhs[0].(*ast.CallExpr)
+	if !ok || !isSelector(call.Fun, "slog", "With") {
+		pass.Reportf(node.Pos(), "logger creation must use slog.With")
+		return
+	}
+	if !lo.ContainsBy(call.Args, loggerCommandKeyValueArgFinder(pass, commandName)) {
+		pass.Reportf(node.Pos(), "logger creation must contain command arg")
+	}
+
+	checkStmtHaveNoRawSlog(pass, node.Body.List[1:])
+}
+
+func checkCommandFunc(pass *analysis.Pass, node *ast.FuncDecl) {
+	if node.Type.Results.NumFields() != 2 {
+		pass.Reportf(node.Pos(), "command function must have 2 return value")
+	} else {
+		if !isIdent(node.Type.Results.List[0].Type, "int") {
+			pass.Reportf(node.Pos(), "command function must return an int code as the first return value")
+		}
+		if !isIdent(node.Type.Results.List[1].Type, "error") {
+			pass.Reportf(node.Pos(), "command function must return an error as the second return value")
+		}
+	}
+	if lo.ContainsBy(node.Type.Params.List, func(field *ast.Field) bool {
+		return isSelector(field.Type, "auth", "User")
+	}) {
+		pass.Reportf(node.Pos(), "command function must not have an auth.User parameter")
+	}
+	checkCommandLogger(pass, node)
+}