API now outputs loot_needs_cleaning_no code.

Fixes #324. Also added tests for the loot_get_dirty_info function, and
documented cases where the loot_needs_cleaning_unknown code may be
mistakenly outputted instead of the loot_needs_cleaning_no code.

src/api/api.cpp

@@ -755,18 +755,28 @@ LOOT_API unsigned int loot_get_dirty_info(loot_db db, const char * const plugin,
 
     *needsCleaning = loot_needs_cleaning_unknown;
 
-    //Get all dirty info.
-    loot::Plugin p = db->masterlist.FindPlugin(loot::Plugin(plugin));
-    std::set<loot::PluginDirtyInfo> dirtyInfo(p.DirtyInfo());
-
-    p = db->userlist.FindPlugin(loot::Plugin(plugin));
-    std::set<loot::PluginDirtyInfo> temp(p.DirtyInfo());
-    dirtyInfo.insert(temp.begin(), temp.end());
-
-    if (!dirtyInfo.empty()) {
+    // Is there any dirty info? Testing for applicability happens in loot_eval_lists().
+    if (!db->masterlist.FindPlugin(loot::Plugin(plugin)).DirtyInfo().empty()
+        || !db->userlist.FindPlugin(loot::Plugin(plugin)).DirtyInfo().empty()) {
         *needsCleaning = loot_needs_cleaning_yes;
     }
 
+    // Is there a message beginning with the substring "Do not clean."?
+    // This isn't a very reliable system, because if the lists have been evaluated in some language
+    // other than English, the strings will be in different languages (and the API can't tell what they'd be)
+    // and the strings may be non-standard and begin with something other than "Do not clean." anyway.
+    std::list<loot::Message> messages(db->masterlist.FindPlugin(loot::Plugin(plugin)).Messages());
+
+    std::list<loot::Message> temp(db->userlist.FindPlugin(loot::Plugin(plugin)).Messages());
+    messages.insert(messages.end(), temp.begin(), temp.end());
+
+    for (const auto& message : messages) {
+        if (boost::starts_with(message.ChooseContent(loot::Language::english).Str(), "Do not clean")) {
+            *needsCleaning = loot_needs_cleaning_no;
+            break;
+        }
+    }
+
     return loot_ok;
 }
 

src/api/api.h

@@ -607,7 +607,12 @@ extern "C"
     /**
      *  @brief Determines the database's knowledge of a plugin's dirtiness.
      *  @details Outputs whether the plugin should be cleaned or not, or if
-     *           no data is available.
+     *           no data is available. The mechanism used to determine that
+     *           a plugin should not be cleaned is not very reliable, and is
+     *           likely to fail if `loot_eval_lists()` was called with a
+     *           language other than English. As such, some plugins that should
+     *           not be cleaned may have the `loot_needs_cleaning_unknown`
+     *           code outputted.
      *  @param db
      *      The database the function acts on.
      *  @param plugin

src/tests/api/api.h

@@ -234,4 +234,28 @@ TEST_F(OblivionAPIOperationsTest, SortPlugins) {
     EXPECT_EQ(11, numPlugins);
     EXPECT_EQ(expectedOrder, actualOrder);
 }
+
+TEST_F(OblivionAPIOperationsTest, GetDirtyInfo) {
+    unsigned int needsCleaning;
+    EXPECT_EQ(loot_error_invalid_args, loot_get_dirty_info(NULL, "Oblivion.esm", &needsCleaning));
+    EXPECT_EQ(loot_error_invalid_args, loot_get_dirty_info(db, NULL, &needsCleaning));
+    EXPECT_EQ(loot_error_invalid_args, loot_get_dirty_info(db, "Oblivion.esm", NULL));
+
+    // Fetch and load the metadata.
+    bool updated;
+    ASSERT_EQ(loot_ok, loot_update_masterlist(db, masterlistPath.string().c_str(), "https://github.com/loot/oblivion.git", "master", &updated));
+    ASSERT_EQ(loot_ok, loot_load_lists(db, masterlistPath.string().c_str(), NULL));
+
+    // A plugin with no metadata.
+    EXPECT_EQ(loot_ok, loot_get_dirty_info(db, "Oblivion.esm", &needsCleaning));
+    EXPECT_EQ(loot_needs_cleaning_unknown, needsCleaning);
+
+    // A plugin with dirty metadata.
+    EXPECT_EQ(loot_ok, loot_get_dirty_info(db, "Hammerfell.esm", &needsCleaning));
+    EXPECT_EQ(loot_needs_cleaning_yes, needsCleaning);
+
+    // A plugin with a standard "Do not clean" message.
+    EXPECT_EQ(loot_ok, loot_get_dirty_info(db, "Unofficial Oblivion Patch.esp", &needsCleaning));
+    EXPECT_EQ(loot_needs_cleaning_no, needsCleaning);
+}
 #endif