fix: avoid double semicolons in extra_lua_path and add usage comments

Author: inkyu-bae

t/APISIX.pm

@@ -272,25 +272,44 @@ _EOC_
     my $extra_lua_path = "";
     my $extra_lua_cpath = "";
 
+    # Support for extra_lua_path / extra_lua_cpath:
+    # These allow tests to load custom plugins from non-standard directories.
+    #
+    # Method 1 - Block definition (preferred, takes precedence):
+    #   --- extra_lua_path
+    #   /path/to/custom/plugins/?.lua;
+    #
+    # Method 2 - Via extra_yaml_config:
+    #   --- extra_yaml_config
+    #   apisix:
+    #     extra_lua_path: "/path/to/custom/plugins/?.lua;"
+    #
+    # The extracted paths are prepended to lua_package_path / lua_package_cpath,
+    # consistent with the runtime behavior in apisix/cli/ops.lua.
+
     # Method 1: Block definition (preferred)
     if ($block->extra_lua_path) {
-        $extra_lua_path = $block->extra_lua_path . ";";
+        $extra_lua_path = $block->extra_lua_path;
+        $extra_lua_path .= ";" unless $extra_lua_path =~ /;$/;
     }
     if ($block->extra_lua_cpath) {
-        $extra_lua_cpath = $block->extra_lua_cpath . ";";
+        $extra_lua_cpath = $block->extra_lua_cpath;
+        $extra_lua_cpath .= ";" unless $extra_lua_cpath =~ /;$/;
     }
 
     # Method 2: Extract from extra_yaml_config if block definition not provided
     if (!$extra_lua_path && $block->extra_yaml_config) {
         my $extra_yaml = $block->extra_yaml_config;
         if ($extra_yaml =~ m/^\s*extra_lua_path:\s*["\']?([^"\'\n]+)["\']?/m) {
-            $extra_lua_path = $1 . ";";
+            $extra_lua_path = $1;
+            $extra_lua_path .= ";" unless $extra_lua_path =~ /;$/;
         }
     }
     if (!$extra_lua_cpath && $block->extra_yaml_config) {
         my $extra_yaml = $block->extra_yaml_config;
         if ($extra_yaml =~ m/^\s*extra_lua_cpath:\s*["\']?([^"\'\n]+)["\']?/m) {
-            $extra_lua_cpath = $1 . ";";
+            $extra_lua_cpath = $1;
+            $extra_lua_cpath .= ";" unless $extra_lua_cpath =~ /;$/;
         }
     }
 

t/admin/extra-lua-path.t

@@ -203,7 +203,88 @@ SUCCESS: block definition takes precedence
 
 
 
-=== TEST 8: Load and execute custom plugin via extra_lua_path
+=== TEST 8: extra_lua_path with trailing semicolon should not produce double semicolons
+Verify that paths already ending with semicolons are handled correctly (no ;; in path)
+--- extra_lua_path: /trailing/semicolon/?.lua;
+--- config
+    location /t {
+        content_by_lua_block {
+            local path = package.path
+            local found = string.find(path, "/trailing/semicolon/?.lua", 1, true)
+            -- Check there is no double semicolon right after the custom path
+            local double_sc = string.find(path, "/trailing/semicolon/?.lua;;", 1, true)
+
+            if found and not double_sc then
+                ngx.say("SUCCESS: trailing semicolon handled correctly")
+            elseif double_sc then
+                ngx.say("FAIL: double semicolons detected in path")
+            else
+                ngx.say("FAIL: path not found")
+            end
+        }
+    }
+--- request
+GET /t
+--- response_body
+SUCCESS: trailing semicolon handled correctly
+
+
+
+=== TEST 9: extra_lua_cpath with trailing semicolon should not produce double semicolons
+Verify that cpaths already ending with semicolons are handled correctly
+--- extra_lua_cpath: /trailing/semicolon/?.so;
+--- config
+    location /t {
+        content_by_lua_block {
+            local cpath = package.cpath
+            local found = string.find(cpath, "/trailing/semicolon/?.so", 1, true)
+            local double_sc = string.find(cpath, "/trailing/semicolon/?.so;;", 1, true)
+
+            if found and not double_sc then
+                ngx.say("SUCCESS: trailing semicolon handled correctly")
+            elseif double_sc then
+                ngx.say("FAIL: double semicolons detected in cpath")
+            else
+                ngx.say("FAIL: cpath not found")
+            end
+        }
+    }
+--- request
+GET /t
+--- response_body
+SUCCESS: trailing semicolon handled correctly
+
+
+
+=== TEST 10: extra_lua_path from yaml_config with trailing semicolon
+Verify that yaml_config paths with trailing semicolons are handled correctly
+--- extra_yaml_config
+apisix:
+  extra_lua_path: "/yaml/trailing/?.lua;"
+--- config
+    location /t {
+        content_by_lua_block {
+            local path = package.path
+            local found = string.find(path, "/yaml/trailing/?.lua", 1, true)
+            local double_sc = string.find(path, "/yaml/trailing/?.lua;;", 1, true)
+
+            if found and not double_sc then
+                ngx.say("SUCCESS: yaml trailing semicolon handled correctly")
+            elseif double_sc then
+                ngx.say("FAIL: double semicolons detected in path")
+            else
+                ngx.say("FAIL: path not found")
+            end
+        }
+    }
+--- request
+GET /t
+--- response_body
+SUCCESS: yaml trailing semicolon handled correctly
+
+
+
+=== TEST 11: Load and execute custom plugin via extra_lua_path
 Verify that a real custom plugin can be loaded and executed using extra_lua_path
 --- extra_lua_path: t/plugin/custom-plugins/?.lua
 --- extra_yaml_config