fix(middleware): normalize MethodOverride method to uppercase

Overridden methods such as "delete" did not match router http.Method*
constants. Trim and uppercase the override value before assigning.

Author: sonnedu

middleware/method_override.go

@@ -5,6 +5,7 @@ package middleware
 
 import (
 	"net/http"
+	"strings"
 
 	"github.com/labstack/echo/v5"
 )
@@ -60,9 +61,10 @@ func (config MethodOverrideConfig) ToMiddleware() (echo.MiddlewareFunc, error) {
 
 			req := c.Request()
 			if req.Method == http.MethodPost {
-				m := config.Getter(c)
+				m := strings.TrimSpace(config.Getter(c))
 				if m != "" {
-					req.Method = m
+					// Normalize to uppercase so routing matches http.Method* constants.
+					req.Method = strings.ToUpper(m)
 				}
 			}
 			return next(c)

middleware/method_override_test.go

@@ -90,3 +90,19 @@ func TestMethodOverride_ignoreGet(t *testing.T) {
 
 	assert.Equal(t, http.MethodGet, req.Method)
 }
+
+func TestMethodOverride_normalizeCase(t *testing.T) {
+	e := echo.New()
+	m := MethodOverride()
+	h := m(func(c *echo.Context) error {
+		return c.String(http.StatusOK, c.Request().Method)
+	})
+
+	req := httptest.NewRequest(http.MethodPost, "/", nil)
+	req.Header.Set(echo.HeaderXHTTPMethodOverride, "delete")
+	rec := httptest.NewRecorder()
+	c := e.NewContext(req, rec)
+	assert.NoError(t, h(c))
+	assert.Equal(t, http.MethodDelete, req.Method)
+	assert.Equal(t, http.MethodDelete, rec.Body.String())
+}