Add a new completion API for experimental plugins feature. (#5000)

Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

CHANGELOG.md

@@ -16,6 +16,7 @@
 - Minor: Add an option to use new experimental smarter emote completion. (#4987)
 - Minor: Add `--safe-mode` command line option that can be used for troubleshooting when Chatterino is misbehaving or is misconfigured. It disables hiding the settings button & prevents plugins from loading. (#4985)
 - Minor: Updated the flatpakref link included with nightly builds to point to up-to-date flathub-beta builds. (#5008)
+- Minor: Add a new completion API for experimental plugins feature. (#5000)
 - Bugfix: Fixed an issue where certain emojis did not send to Twitch chat correctly. (#4840)
 - Bugfix: Fixed capitalized channel names in log inclusion list not being logged. (#4848)
 - Bugfix: Trimmed custom streamlink paths on all platforms making sure you don't accidentally add spaces at the beginning or end of its path. (#4834)

docs/chatterino.d.ts

@@ -19,4 +19,25 @@ declare module c2 {
   ): boolean;
   function send_msg(channel: String, text: String): boolean;
   function system_msg(channel: String, text: String): boolean;
+
+  class CompletionList {
+    values: String[];
+    hide_others: boolean;
+  }
+
+  enum EventType {
+    RegisterCompletions = "RegisterCompletions",
+  }
+
+  type CbFuncCompletionsRequested = (
+    query: string,
+    full_text_content: string,
+    cursor_position: number,
+    is_first_word: boolean
+  ) => CompletionList;
+  type CbFunc<T> = T extends EventType.RegisterCompletions
+    ? CbFuncCompletionsRequested
+    : never;
+
+  function register_callback<T>(type: T, func: CbFunc<T>): void;
 }

src/controllers/completion/TabCompletionModel.cpp

@@ -1,5 +1,6 @@
 #include "controllers/completion/TabCompletionModel.hpp"
 
+#include "Application.hpp"
 #include "common/Channel.hpp"
 #include "controllers/completion/sources/CommandSource.hpp"
 #include "controllers/completion/sources/EmoteSource.hpp"
@@ -9,6 +10,9 @@
 #include "controllers/completion/strategies/ClassicUserStrategy.hpp"
 #include "controllers/completion/strategies/CommandStrategy.hpp"
 #include "controllers/completion/strategies/SmartEmoteStrategy.hpp"
+#include "controllers/plugins/LuaUtilities.hpp"
+#include "controllers/plugins/Plugin.hpp"
+#include "controllers/plugins/PluginController.hpp"
 #include "singletons/Settings.hpp"
 
 namespace chatterino {
@@ -19,7 +23,9 @@ TabCompletionModel::TabCompletionModel(Channel &channel, QObject *parent)
 {
 }
 
-void TabCompletionModel::updateResults(const QString &query, bool isFirstWord)
+void TabCompletionModel::updateResults(const QString &query,
+                                       const QString &fullTextContent,
+                                       int cursorPosition, bool isFirstWord)
 {
     this->updateSourceFromQuery(query);
 
@@ -29,6 +35,17 @@ void TabCompletionModel::updateResults(const QString &query, bool isFirstWord)
 
         // Copy results to this model
         QStringList results;
+#ifdef CHATTERINO_HAVE_PLUGINS
+        // Try plugins first
+        bool done{};
+        std::tie(done, results) = getApp()->plugins->updateCustomCompletions(
+            query, fullTextContent, cursorPosition, isFirstWord);
+        if (done)
+        {
+            this->setStringList(results);
+            return;
+        }
+#endif
         this->source_->addToStringList(results, 0, isFirstWord);
         this->setStringList(results);
     }

src/controllers/completion/TabCompletionModel.hpp

@@ -26,8 +26,12 @@ public:
 
     /// @brief Updates the model based on the completion query
     /// @param query Completion query
+    /// @param fullTextContent Full text of the input, used by plugins for contextual completion
+    /// @param cursorPosition Number of characters behind the cursor from the
+    /// beginning of fullTextContent, also used by plugins
     /// @param isFirstWord Whether the completion is the first word in the input
-    void updateResults(const QString &query, bool isFirstWord = false);
+    void updateResults(const QString &query, const QString &fullTextContent,
+                       int cursorPosition, bool isFirstWord = false);
 
 private:
     enum class SourceKind {

src/controllers/plugins/LuaAPI.cpp

@@ -94,6 +94,37 @@ int c2_register_command(lua_State *L)
     return 1;
 }
 
+int c2_register_callback(lua_State *L)
+{
+    auto *pl = getApp()->plugins->getPluginByStatePtr(L);
+    if (pl == nullptr)
+    {
+        luaL_error(L, "internal error: no plugin");
+        return 0;
+    }
+    EventType evtType{};
+    if (!lua::peek(L, &evtType, 1))
+    {
+        luaL_error(L, "cannot get event name (1st arg of register_callback, "
+                      "expected a string)");
+        return 0;
+    }
+    if (lua_isnoneornil(L, 2))
+    {
+        luaL_error(L, "missing argument for register_callback: function "
+                      "\"pointer\"");
+        return 0;
+    }
+
+    auto callbackSavedName = QString("c2cb-%1").arg(
+        magic_enum::enum_name<EventType>(evtType).data());
+    lua_setfield(L, LUA_REGISTRYINDEX, callbackSavedName.toStdString().c_str());
+
+    lua_pop(L, 2);
+
+    return 0;
+}
+
 int c2_send_msg(lua_State *L)
 {
     QString text;
@@ -167,6 +198,7 @@ int c2_system_msg(lua_State *L)
         lua::push(L, false);
         return 1;
     }
+
     const auto chn = getApp()->twitch->getChannelOrEmpty(channel);
     if (chn->isEmpty())
     {

src/controllers/plugins/LuaAPI.hpp

@@ -1,14 +1,18 @@
 #pragma once
 
 #ifdef CHATTERINO_HAVE_PLUGINS
+#    include <QString>
+
+#    include <vector>
 
 struct lua_State;
 namespace chatterino::lua::api {
-// names in this namespace reflect what's visible inside Lua and follow the lua naming scheme
+// function names in this namespace reflect what's visible inside Lua and follow the lua naming scheme
 
 // NOLINTBEGIN(readability-identifier-naming)
 // Following functions are exposed in c2 table.
 int c2_register_command(lua_State *L);
+int c2_register_callback(lua_State *L);
 int c2_send_msg(lua_State *L);
 int c2_system_msg(lua_State *L);
 int c2_log(lua_State *L);
@@ -23,6 +27,24 @@ int g_import(lua_State *L);
 // Represents "calls" to qCDebug, qCInfo ...
 enum class LogLevel { Debug, Info, Warning, Critical };
 
+// Exposed as c2.EventType
+// Represents callbacks c2 can do into lua world
+enum class EventType {
+    CompletionRequested,
+};
+
+/**
+ * This is for custom completion, a registered function returns this type
+ * however in Lua array part (value) and object part (hideOthers) are in the same
+ * table.
+ */
+struct CompletionList {
+    std::vector<QString> values{};
+
+    // exposed as hide_others
+    bool hideOthers{};
+};
+
 }  // namespace chatterino::lua::api
 
 #endif

src/controllers/plugins/LuaUtilities.cpp

@@ -4,6 +4,7 @@
 #    include "common/Channel.hpp"
 #    include "common/QLogging.hpp"
 #    include "controllers/commands/CommandContext.hpp"
+#    include "controllers/plugins/LuaAPI.hpp"
 
 #    include <lauxlib.h>
 #    include <lua.h>
@@ -75,6 +76,9 @@ QString humanErrorText(lua_State *L, int errCode)
         case LUA_ERRFILE:
             errName = "(file error)";
             break;
+        case ERROR_BAD_PEEK:
+            errName = "(unable to convert value to c++)";
+            break;
         default:
             errName = "(unknown error type)";
     }
@@ -111,6 +115,7 @@ StackIdx push(lua_State *L, const std::string &str)
 
 StackIdx push(lua_State *L, const CommandContext &ctx)
 {
+    StackGuard guard(L, 1);
     auto outIdx = pushEmptyTable(L, 2);
 
     push(L, ctx.words);
@@ -127,8 +132,27 @@ StackIdx push(lua_State *L, const bool &b)
     return lua_gettop(L);
 }
 
+StackIdx push(lua_State *L, const int &b)
+{
+    lua_pushinteger(L, b);
+    return lua_gettop(L);
+}
+
+bool peek(lua_State *L, bool *out, StackIdx idx)
+{
+    StackGuard guard(L);
+    if (!lua_isboolean(L, idx))
+    {
+        return false;
+    }
+
+    *out = bool(lua_toboolean(L, idx));
+    return true;
+}
+
 bool peek(lua_State *L, double *out, StackIdx idx)
 {
+    StackGuard guard(L);
     int ok{0};
     auto v = lua_tonumberx(L, idx, &ok);
     if (ok != 0)
@@ -140,6 +164,7 @@ bool peek(lua_State *L, double *out, StackIdx idx)
 
 bool peek(lua_State *L, QString *out, StackIdx idx)
 {
+    StackGuard guard(L);
     size_t len{0};
     const char *str = lua_tolstring(L, idx, &len);
     if (str == nullptr)
@@ -156,6 +181,7 @@ bool peek(lua_State *L, QString *out, StackIdx idx)
 
 bool peek(lua_State *L, QByteArray *out, StackIdx idx)
 {
+    StackGuard guard(L);
     size_t len{0};
     const char *str = lua_tolstring(L, idx, &len);
     if (str == nullptr)
@@ -172,6 +198,7 @@ bool peek(lua_State *L, QByteArray *out, StackIdx idx)
 
 bool peek(lua_State *L, std::string *out, StackIdx idx)
 {
+    StackGuard guard(L);
     size_t len{0};
     const char *str = lua_tolstring(L, idx, &len);
     if (str == nullptr)
@@ -186,6 +213,23 @@ bool peek(lua_State *L, std::string *out, StackIdx idx)
     return true;
 }
 
+bool peek(lua_State *L, api::CompletionList *out, StackIdx idx)
+{
+    StackGuard guard(L);
+    int typ = lua_getfield(L, idx, "values");
+    if (typ != LUA_TTABLE)
+    {
+        lua_pop(L, 1);
+        return false;
+    }
+    if (!lua::pop(L, &out->values, -1))
+    {
+        return false;
+    }
+    lua_getfield(L, idx, "hide_others");
+    return lua::pop(L, &out->hideOthers);
+}
+
 QString toString(lua_State *L, StackIdx idx)
 {
     size_t len{};

src/controllers/plugins/LuaUtilities.hpp

@@ -2,14 +2,19 @@
 
 #ifdef CHATTERINO_HAVE_PLUGINS
 
+#    include "common/QLogging.hpp"
+
 #    include <lua.h>
 #    include <lualib.h>
 #    include <magic_enum/magic_enum.hpp>
 #    include <QList>
 
+#    include <cassert>
+#    include <optional>
 #    include <string>
 #    include <string_view>
 #    include <type_traits>
+#    include <variant>
 #    include <vector>
 struct lua_State;
 class QJsonObject;
@@ -19,6 +24,12 @@ struct CommandContext;
 
 namespace chatterino::lua {
 
+namespace api {
+    struct CompletionList;
+}  // namespace api
+
+constexpr int ERROR_BAD_PEEK = LUA_OK - 1;
+
 /**
  * @brief Dumps the Lua stack into qCDebug(chatterinoLua)
  *
@@ -52,20 +63,136 @@ StackIdx push(lua_State *L, const CommandContext &ctx);
 StackIdx push(lua_State *L, const QString &str);
 StackIdx push(lua_State *L, const std::string &str);
 StackIdx push(lua_State *L, const bool &b);
+StackIdx push(lua_State *L, const int &b);
 
 // returns OK?
+bool peek(lua_State *L, bool *out, StackIdx idx = -1);
 bool peek(lua_State *L, double *out, StackIdx idx = -1);
 bool peek(lua_State *L, QString *out, StackIdx idx = -1);
 bool peek(lua_State *L, QByteArray *out, StackIdx idx = -1);
 bool peek(lua_State *L, std::string *out, StackIdx idx = -1);
+bool peek(lua_State *L, api::CompletionList *out, StackIdx idx = -1);
 
 /**
  * @brief Converts Lua object at stack index idx to a string.
  */
 QString toString(lua_State *L, StackIdx idx = -1);
 
+// This object ensures that the stack is of expected size when it is destroyed
+class StackGuard
+{
+    int expected;
+    lua_State *L;
+
+public:
+    /**
+     * Use this constructor if you expect the stack size to be the same on the
+     * destruction of the object as its creation
+     */
+    StackGuard(lua_State *L)
+        : expected(lua_gettop(L))
+        , L(L)
+    {
+    }
+
+    /**
+     * Use this if you expect the stack size changing, diff is the expected difference
+     * Ex: diff=3 means three elements added to the stack
+     */
+    StackGuard(lua_State *L, int diff)
+        : expected(lua_gettop(L) + diff)
+        , L(L)
+    {
+    }
+
+    ~StackGuard()
+    {
+        if (expected < 0)
+        {
+            return;
+        }
+        int after = lua_gettop(this->L);
+        if (this->expected != after)
+        {
+            stackDump(this->L, "StackGuard check tripped");
+            // clang-format off
+            // clang format likes to insert a new line which means that some builds won't show this message fully
+            assert(false && "internal error: lua stack was not in an expected state");
+            // clang-format on
+        }
+    }
+
+    // This object isn't meant to be passed around
+    StackGuard operator=(StackGuard &) = delete;
+    StackGuard &operator=(StackGuard &&) = delete;
+    StackGuard(StackGuard &) = delete;
+    StackGuard(StackGuard &&) = delete;
+
+    // This function tells the StackGuard that the stack isn't in an expected state but it was handled
+    void handled()
+    {
+        this->expected = -1;
+    }
+};
+
 /// TEMPLATES
 
+template <typename T>
+bool peek(lua_State *L, std::optional<T> *out, StackIdx idx = -1)
+{
+    if (lua_isnil(L, idx))
+    {
+        *out = std::nullopt;
+        return true;
+    }
+
+    *out = T();
+    return peek(L, out->operator->(), idx);
+}
+
+template <typename T>
+bool peek(lua_State *L, std::vector<T> *vec, StackIdx idx = -1)
+{
+    StackGuard guard(L);
+
+    if (!lua_istable(L, idx))
+    {
+        lua::stackDump(L, "!table");
+        qCDebug(chatterinoLua)
+            << "value is not a table, type is" << lua_type(L, idx);
+        return false;
+    }
+    auto len = lua_rawlen(L, idx);
+    if (len == 0)
+    {
+        qCDebug(chatterinoLua) << "value has 0 length";
+        return true;
+    }
+    if (len > 1'000'000)
+    {
+        qCDebug(chatterinoLua) << "value is too long";
+        return false;
+    }
+    // count like lua
+    for (int i = 1; i <= len; i++)
+    {
+        lua_geti(L, idx, i);
+        std::optional<T> obj;
+        if (!lua::peek(L, &obj))
+        {
+            //lua_seti(L, LUA_REGISTRYINDEX, 1);  // lazy
+            qCDebug(chatterinoLua)
+                << "Failed to convert lua object into c++: at array index " << i
+                << ":";
+            stackDump(L, "bad conversion into string");
+            return false;
+        }
+        lua_pop(L, 1);
+        vec->push_back(obj.value());
+    }
+    return true;
+}
+
 /**
  * @brief Converts object at stack index idx to enum given by template parameter T
  */
@@ -150,6 +277,7 @@ StackIdx push(lua_State *L, T inp)
 template <typename T>
 bool pop(lua_State *L, T *out, StackIdx idx = -1)
 {
+    StackGuard guard(L, -1);
     auto ok = peek(L, out, idx);
     if (ok)
     {
@@ -186,6 +314,58 @@ StackIdx pushEnumTable(lua_State *L)
     return out;
 }
 
+// Represents a Lua function on the stack
+template <typename ReturnType, typename... Args>
+class CallbackFunction
+{
+    StackIdx stackIdx_;
+    lua_State *L;
+
+public:
+    CallbackFunction(lua_State *L, StackIdx stackIdx)
+        : stackIdx_(stackIdx)
+        , L(L)
+    {
+    }
+
+    // this type owns the stackidx, it must not be trivially copiable
+    CallbackFunction operator=(CallbackFunction &) = delete;
+    CallbackFunction(CallbackFunction &) = delete;
+
+    // Permit only move
+    CallbackFunction &operator=(CallbackFunction &&) = default;
+    CallbackFunction(CallbackFunction &&) = default;
+
+    ~CallbackFunction()
+    {
+        lua_remove(L, this->stackIdx_);
+    }
+
+    std::variant<int, ReturnType> operator()(Args... arguments)
+    {
+        lua_pushvalue(this->L, this->stackIdx_);
+        (  // apparently this calls lua::push() for every Arg
+            [this, &arguments] {
+                lua::push(this->L, arguments);
+            }(),
+            ...);
+
+        int res = lua_pcall(L, sizeof...(Args), 1, 0);
+        if (res != LUA_OK)
+        {
+            qCDebug(chatterinoLua) << "error is: " << res;
+            return {res};
+        }
+
+        ReturnType val;
+        if (!lua::pop(L, &val))
+        {
+            return {ERROR_BAD_PEEK};
+        }
+        return {val};
+    }
+};
+
 }  // namespace chatterino::lua
 
 #endif

src/controllers/plugins/Plugin.hpp

@@ -2,6 +2,8 @@
 
 #ifdef CHATTERINO_HAVE_PLUGINS
 #    include "Application.hpp"
+#    include "controllers/plugins/LuaAPI.hpp"
+#    include "controllers/plugins/LuaUtilities.hpp"
 
 #    include <QDir>
 #    include <QString>
@@ -85,10 +87,51 @@ public:
         return this->loadDirectory_;
     }
 
+    // Note: The CallbackFunction object's destructor will remove the function from the lua stack
+    using LuaCompletionCallback =
+        lua::CallbackFunction<lua::api::CompletionList, QString, QString, int,
+                              bool>;
+    std::optional<LuaCompletionCallback> getCompletionCallback()
+    {
+        if (this->state_ == nullptr || !this->error_.isNull())
+        {
+            return {};
+        }
+        // this uses magic enum to help automatic tooling find usages
+        auto typ =
+            lua_getfield(this->state_, LUA_REGISTRYINDEX,
+                         QString("c2cb-%1")
+                             .arg(magic_enum::enum_name<lua::api::EventType>(
+                                      lua::api::EventType::CompletionRequested)
+                                      .data())
+                             .toStdString()
+                             .c_str());
+        if (typ != LUA_TFUNCTION)
+        {
+            lua_pop(this->state_, 1);
+            return {};
+        }
+
+        // move
+        return std::make_optional<lua::CallbackFunction<
+            lua::api::CompletionList, QString, QString, int, bool>>(
+            this->state_, lua_gettop(this->state_));
+    }
+
+    /**
+     * If the plugin crashes while evaluating the main file, this function will return the error
+     */
+    QString error()
+    {
+        return this->error_;
+    }
+
 private:
     QDir loadDirectory_;
     lua_State *state_;
 
+    QString error_;
+
     // maps command name -> function name
     std::unordered_map<QString, QString> ownedCommands;
 

src/controllers/plugins/PluginController.cpp

@@ -19,6 +19,7 @@
 
 #    include <memory>
 #    include <utility>
+#    include <variant>
 
 namespace chatterino {
 
@@ -46,15 +47,13 @@ void PluginController::loadPlugins()
     auto dir = QDir(getPaths()->pluginsDirectory);
     qCDebug(chatterinoLua) << "Loading plugins in" << dir.path();
     for (const auto &info :
-         dir.entryInfoList(QDir::NoFilter | QDir::NoDotAndDotDot))
+         dir.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot))
     {
-        if (info.isDir())
-        {
-            auto pluginDir = QDir(info.absoluteFilePath());
-            this->tryLoadFromDir(pluginDir);
-        }
+        auto pluginDir = QDir(info.absoluteFilePath());
+        this->tryLoadFromDir(pluginDir);
     }
 }
+
 bool PluginController::tryLoadFromDir(const QDir &pluginDir)
 {
     // look for init.lua
@@ -139,6 +138,7 @@ void PluginController::openLibrariesFor(lua_State *L,
     static const luaL_Reg c2Lib[] = {
         {"system_msg", lua::api::c2_system_msg},
         {"register_command", lua::api::c2_register_command},
+        {"register_callback", lua::api::c2_register_callback},
         {"send_msg", lua::api::c2_send_msg},
         {"log", lua::api::c2_log},
         {nullptr, nullptr},
@@ -146,14 +146,17 @@ void PluginController::openLibrariesFor(lua_State *L,
     lua_pushglobaltable(L);
     auto global = lua_gettop(L);
 
-    // count of elements in C2LIB + LogLevel
-    auto c2libIdx = lua::pushEmptyTable(L, 5);
+    // count of elements in C2LIB + LogLevel + EventType
+    auto c2libIdx = lua::pushEmptyTable(L, 8);
 
     luaL_setfuncs(L, c2Lib, 0);
 
     lua::pushEnumTable<lua::api::LogLevel>(L);
     lua_setfield(L, c2libIdx, "LogLevel");
 
+    lua::pushEnumTable<lua::api::EventType>(L);
+    lua_setfield(L, c2libIdx, "EventType");
+
     lua_setfield(L, global, "c2");
 
     // ban functions
@@ -198,6 +201,7 @@ void PluginController::load(const QFileInfo &index, const QDir &pluginDir,
     auto pluginName = pluginDir.dirName();
     lua_State *l = luaL_newstate();
     auto plugin = std::make_unique<Plugin>(pluginName, l, meta, pluginDir);
+    auto *temp = plugin.get();
     this->plugins_.insert({pluginName, std::move(plugin)});
 
     if (getArgs().safeMode)
@@ -220,9 +224,10 @@ void PluginController::load(const QFileInfo &index, const QDir &pluginDir,
     int err = luaL_dofile(l, index.absoluteFilePath().toStdString().c_str());
     if (err != 0)
     {
+        temp->error_ = lua::humanErrorText(l, err);
         qCWarning(chatterinoLua)
             << "Failed to load" << pluginName << "plugin from" << index << ": "
-            << lua::humanErrorText(l, err);
+            << temp->error_;
         return;
     }
     qCInfo(chatterinoLua) << "Loaded" << pluginName << "plugin from" << index;
@@ -307,5 +312,52 @@ const std::map<QString, std::unique_ptr<Plugin>> &PluginController::plugins()
     return this->plugins_;
 }
 
-};  // namespace chatterino
+std::pair<bool, QStringList> PluginController::updateCustomCompletions(
+    const QString &query, const QString &fullTextContent, int cursorPosition,
+    bool isFirstWord) const
+{
+    QStringList results;
+
+    for (const auto &[name, pl] : this->plugins())
+    {
+        if (!pl->error().isNull())
+        {
+            continue;
+        }
+
+        lua::StackGuard guard(pl->state_);
+
+        auto opt = pl->getCompletionCallback();
+        if (opt)
+        {
+            qCDebug(chatterinoLua)
+                << "Processing custom completions from plugin" << name;
+            auto &cb = *opt;
+            auto errOrList =
+                cb(query, fullTextContent, cursorPosition, isFirstWord);
+            if (std::holds_alternative<int>(errOrList))
+            {
+                guard.handled();
+                int err = std::get<int>(errOrList);
+                qCDebug(chatterinoLua)
+                    << "Got error from plugin " << pl->meta.name
+                    << " while refreshing tab completion: "
+                    << lua::humanErrorText(pl->state_, err);
+                continue;
+            }
+
+            auto list = std::get<lua::api::CompletionList>(errOrList);
+            if (list.hideOthers)
+            {
+                results = QStringList(list.values.begin(), list.values.end());
+                return {true, results};
+            }
+            results += QStringList(list.values.begin(), list.values.end());
+        }
+    }
+
+    return {false, results};
+}
+
+}  // namespace chatterino
 #endif

src/controllers/plugins/PluginController.hpp

@@ -36,6 +36,7 @@ public:
     // This is required to be public because of c functions
     Plugin *getPluginByStatePtr(lua_State *L);
 
+    // TODO: make a function that iterates plugins that aren't errored/enabled
     const std::map<QString, std::unique_ptr<Plugin>> &plugins() const;
 
     /**
@@ -52,6 +53,10 @@ public:
      */
     static bool isPluginEnabled(const QString &id);
 
+    std::pair<bool, QStringList> updateCustomCompletions(
+        const QString &query, const QString &fullTextContent,
+        int cursorPosition, bool isFirstWord) const;
+
 private:
     void loadPlugins();
     void load(const QFileInfo &index, const QDir &pluginDir,
@@ -64,5 +69,5 @@ private:
     std::map<QString, std::unique_ptr<Plugin>> plugins_;
 };
 
-};  // namespace chatterino
+}  // namespace chatterino
 #endif

src/widgets/helper/ResizingTextEdit.cpp

@@ -170,8 +170,9 @@ void ResizingTextEdit::keyPressEvent(QKeyEvent *event)
             // First type pressing tab after modifying a message, we refresh our
             // completion model
             this->completer_->setModel(completionModel);
-            completionModel->updateResults(currentCompletion,
-                                           this->isFirstWord());
+            completionModel->updateResults(
+                currentCompletion, this->toPlainText(),
+                this->textCursor().position(), this->isFirstWord());
             this->completionInProgress_ = true;
             {
                 // this blocks cursor movement events from resetting tab completion

src/widgets/settingspages/PluginsPage.cpp

@@ -108,6 +108,16 @@ void PluginsPage::rebuildContent()
             warningLabel->setStyleSheet("color: #f00");
             pluginEntry->addRow(warningLabel);
         }
+        if (!plugin->error().isNull())
+        {
+            auto *errorLabel =
+                new QLabel("There was an error while loading this plugin: " +
+                               plugin->error(),
+                           this->dataFrame_);
+            errorLabel->setStyleSheet("color: #f00");
+            errorLabel->setWordWrap(true);
+            pluginEntry->addRow(errorLabel);
+        }
 
         auto *description =
             new QLabel(plugin->meta.description, this->dataFrame_);