test & fix left-out codeowners path

Author: comatory

lua/gh-co/co.lua

@@ -116,8 +116,18 @@ CO.matchFilesToCodeowner = function(filePaths)
 
   sortMatches(matches)
 
-  local codeownersList = mapCodeowners(matches)
-
+  -- Only use the most specific pattern(s) - those with the longest pathPattern
+  local maxLength = #matches[1].pathPattern
+  local mostSpecificMatches = {}
+  for _, match in ipairs(matches) do
+    if #match.pathPattern == maxLength then
+      table.insert(mostSpecificMatches, match)
+    else
+      break -- Since sorted by length, we can break early
+    end
+  end
+  
+  local codeownersList = mapCodeowners(mostSpecificMatches)
   return codeownersList
 end
 

lua/gh-co/co.test.lua

@@ -271,4 +271,23 @@ function TestCO:testDoubleStarLogsPattern() -- luacheck: ignore 212
   lu.assertEquals(result, {"@octocat"})
 end
 
+function TestCO:testAppsWithEmptyGithubSubdirectory() -- luacheck: ignore 212
+  -- Test /apps/ with empty /apps/github (no owners)
+  self.FS.openCodeownersFileAsLines = function()
+    local lines = {
+      "/apps/ @octocat",
+      "/apps/github"
+    }
+    local i = 0
+    return function()
+      i = i + 1
+      return lines[i]
+    end
+  end
+  
+  -- Files in /apps/github should have no owners (empty pattern overrides /apps/)
+  local githubResult = CO.matchFilesToCodeowner({"/apps/github/readme.md"})
+  lu.assertEquals(githubResult, {})
+end
+
 os.exit(lu.LuaUnit.run())