luci-base: ensure that file upload values have length

Ensure that the (table) length of a file upload value has nonzero length
by initializing the first table index with the file name.

This fixes tests in the form

    x = luci.http.formvalue(...)
    if x and #x > 0 then ... end

Fixes #1763.
Signed-off-by: Jo-Philipp Wich <jo@mein.io>

diff --git a/modules/luci-base/luasrc/http.lua b/modules/luci-base/luasrc/http.lua
index 56d0064..be5577e 100644 (file)
--- a/modules/luci-base/luasrc/http.lua
+++ b/modules/luci-base/luasrc/http.lua
@@ -359,6 +359,7 @@ function mimedecode_message_body(src, msg, file_cb)
                        then
                                field.name = lhttp.header_attribute(buffer, "name")
                                field.file = lhttp.header_attribute(buffer, "filename")
+                               field[1] = field.file
                        end
 
                        if field.headers then