Nginx configuration skipping if statement in parent location block - if-statement

Question

I have the following setup:
location #public {
auth_basic off;
}
location #webdav {
proxy_set_header Host $host;
proxy_pass http://localhost:8080;
}
location / {
# WebDAV server
if ($request_method != GET) {
error_page 418 = #webdav;
return 418;
}
gzip on;
fancyindex on;
location ~ /(public|\.well-known)/ {
if ($remote_user = "") {
error_page 418 = #public;
return 418;
}
}
location = /robots.txt {
add_header Content-Type text/plain;
return 200 "User-agent: *\nDisallow: /\n";
}
}
I want to redirect every non-GET request to my internal WebDAV handler written in Go. The /public folder should be accessible without basic auth, unlike the rest of the filesystem.
However, for nested location blocks, my parent if statement seems to be ignored. Attempting any non-GET request on /public results in 505, and on /robots.txt returns my configured text. However, this is not the case with gzip or fancyindex, as both /public and robots.txt are gzipped and fancy indexed.

Answer 1

Turns out the problem was the order in which nginx processes blocks. The two nested location blocks are executed first, and only then the parent location statements. Since my nested location blocks both return, the parent location statements are never reached. The solution was to add my WebDAV code to the beginning of each of these nested location blocks. Final code:
location #public {
auth_basic off;
}
location #webdav {
proxy_set_header Host $host;
proxy_pass http://localhost:8080;
}
location / {
# WebDAV server
if ($request_method != GET) {
error_page 418 = #webdav;
return 418;
}
gzip on;
fancyindex on;
location ~ /(public|\.well-known)/ {
# WebDAV server
if ($request_method != GET) {
error_page 418 = #webdav;
return 418;
}
if ($remote_user = "") {
error_page 418 = #public;
return 418;
}
}
location = /robots.txt {
# WebDAV server
if ($request_method != GET) {
error_page 418 = #webdav;
return 418;
}
add_header Content-Type text/plain;
return 200 "User-agent: *\nDisallow: /\n";
}
}