Merge pull request #3 from avorima/scan-host-literal

Ignore string literals without colon

Author: stbenjam

pkg/analyzer/analyzer.go

@@ -5,6 +5,7 @@ import (
 	"go/ast"
 	"go/token"
 	"regexp"
+	"strings"
 
 	"golang.org/x/tools/go/analysis/passes/inspect"
 	"golang.org/x/tools/go/ast/inspector"
@@ -86,10 +87,20 @@ func checkForHostPortConstruction(sprintf *ast.CallExpr) error {
 		regexp.MustCompile(`^[a-zA-Z][a-zA-Z0-9+-.]*://[^/]*@%s:.*$`), // URL with basic auth
 	}
 
-	for _, re := range regexes {
-		if re.MatchString(fs) {
-			return fmt.Errorf("host:port in url should be constructed with net.JoinHostPort and not directly with fmt.Sprintf")
+	for idx, re := range regexes {
+		if !re.MatchString(fs) {
+			continue
 		}
+
+		// Match without basic auth and only handle cases where the hostname and optionally the port are specified.
+		if idx == 0 && len(sprintf.Args) <= 3 {
+			arg, ok := getStringLiteral(sprintf.Args, 1)
+			if ok && !strings.Contains(arg, ":") {
+				continue
+			}
+		}
+
+		return fmt.Errorf("host:port in url should be constructed with net.JoinHostPort and not directly with fmt.Sprintf")
 	}
 
 	return nil

testdata/src/p/p.go

@@ -27,20 +27,27 @@ func _() {
 
 	_ = fmt.Sprintf("http://example.com:9211")
 
-	_ = fmt.Sprintf("gopher://%s:%d", "myHost", 70) // want "should be constructed with net.JoinHostPort"
+	_ = fmt.Sprintf("gopher://%s:%d", "myHost", 70)
 
-	_ = fmt.Sprintf("telnet+ssl://%s:%d", "myHost", 23) // want "should be constructed with net.JoinHostPort"
+	_ = fmt.Sprintf("telnet+ssl://%s:%d", "myHost", 23)
 
-	_ = fmt.Sprintf("weird3.6://%s:%d", "myHost", 23) // want "should be constructed with net.JoinHostPort"
+	_ = fmt.Sprintf("weird3.6://%s:%d", "myHost", 23)
 
 	_ = fmt.Sprintf("https://user@%s:%d", "myHost", 8443) // want "should be constructed with net.JoinHostPort"
 
 	_ = fmt.Sprintf("postgres://%s:%s@%s:5050/%s", "foo", "bar", "baz", "qux") // want "should be constructed with net.JoinHostPort"
 
-	_ = fmt.Sprintf("https://%s:%d", "myHost", 8443) // want "should be constructed with net.JoinHostPort"
+	_ = fmt.Sprintf("https://%s:%d", "myHost", 8443)
 
-	_ = fmt.Sprintf("https://%s:9211", "myHost") // want "should be constructed with net.JoinHostPort"
+	_ = fmt.Sprintf("https://%s:9211", "myHost")
+
+	_ = fmt.Sprintf("postgres://%s:%s@%s:5050/%s", "myHost") // want "should be constructed with net.JoinHostPort"
+
+	_ = fmt.Sprintf("https://%s:9211", "my:Host") // want "should be constructed with net.JoinHostPort"
 
 	ip := "fd00::1"
 	_ = fmt.Sprintf("http://%s:1936/healthz", ip) // want "should be constructed with net.JoinHostPort"
-}
+
+	const host = "myHost"
+	_ = fmt.Sprintf("https://%s:9211", host) // want "should be constructed with net.JoinHostPort"
+}