Immediately execute ModuleLoaded hooks for already loaded modules

This is trickier than expected because ModuleLoaded hooks can (as
any other hooks) use arbitrary regular expressions for their filter.

Fixes #4841

9 files changed, 80 insertions, 32 deletions

diff --git a/src/command_manager.cc b/src/command_manager.cc
index ff7a143b..13d79b2d 100644
--- a/src/command_manager.cc
+++ b/src/command_manager.cc
@@ -90,6 +90,13 @@ void CommandManager::load_module(StringView module_name, Context& context)
     context.hooks().run_hook(Hook::ModuleLoaded, module_name, context);
 }
 
+HashSet<String> CommandManager::loaded_modules() const
+{
+    return m_modules | filter([](auto&& elem) { return elem.value.state == Module::State::Loaded; })
+                     | transform([](auto&& elem) { return elem.key; })
+                     | gather<HashSet>();
+}
+
 struct parse_error : runtime_error
 {
     parse_error(StringView error)
diff --git a/src/command_manager.hh b/src/command_manager.hh
index d41c1dcf..503e1977 100644
--- a/src/command_manager.hh
+++ b/src/command_manager.hh
@@ -123,6 +123,7 @@ public:
     void register_module(String module_name, String commands);
 
     void load_module(StringView module_name, Context& context);
+    HashSet<String> loaded_modules() const;
 
     Completions complete_module_name(StringView query) const;
 
diff --git a/src/commands.cc b/src/commands.cc
index bb067699..5dc5f3f7 100644
--- a/src/commands.cc
+++ b/src/commands.cc
@@ -1127,7 +1127,7 @@ const CommandDesc add_hook_cmd = {
         const auto flags = (parser.get_switch("always") ? HookFlags::Always : HookFlags::None) |
                            (parser.get_switch("once")   ? HookFlags::Once   : HookFlags::None);
         get_scope(parser[0], context).hooks().add_hook(it->value, group.str(), flags,
-                                                       std::move(regex), command);
+                                                       std::move(regex), command, context);
     }
 };
 
diff --git a/src/hook_manager.cc b/src/hook_manager.cc
index 6e3ae178..406b803f 100644
--- a/src/hook_manager.cc
+++ b/src/hook_manager.cc
@@ -20,16 +20,62 @@ struct HookManager::HookData
     HookFlags flags;
     Regex filter;
     String commands;
+
+    bool should_run(bool only_always, const Regex& disabled_hooks, StringView param,
+                    MatchResults<const char*>& captures) const
+    {
+        return (not only_always or (flags & HookFlags::Always)) and
+                (group.empty() or disabled_hooks.empty() or
+                 not regex_match(group.begin(), group.end(), disabled_hooks))
+                and regex_match(param.begin(), param.end(), captures, filter);
+    }
+
+    void exec(Hook hook, StringView param, Context& context, const MatchResults<const char*>& captures)
+    {
+        if (context.options()["debug"].get<DebugFlags>() & DebugFlags::Hooks)
+            write_to_debug_buffer(format("hook {}({})/{}",
+                                  enum_desc(Meta::Type<Hook>{})[to_underlying(hook)].name,
+                                  param, group));
+
+        ScopedSetBool disable_history{context.history_disabled()};
+
+        EnvVarMap env_vars{ {"hook_param", param.str()} };
+        for (size_t i = 0; i < captures.size(); ++i)
+            env_vars.insert({format("hook_param_capture_{}", i),
+                             {captures[i].first, captures[i].second}});
+        for (auto& c : filter.impl()->named_captures)
+            env_vars.insert({format("hook_param_capture_{}", c.name),
+                             {captures[c.index].first, captures[c.index].second}});
+
+        CommandManager::instance().execute(commands, context, {{}, std::move(env_vars)});
+    }
+
 };
 
 HookManager::HookManager() : m_parent(nullptr) {}
 HookManager::HookManager(HookManager& parent) : SafeCountable{}, m_parent(&parent) {}
 HookManager::~HookManager() = default;
 
-void HookManager::add_hook(Hook hook, String group, HookFlags flags, Regex filter, String commands)
+void HookManager::add_hook(Hook hook, String group, HookFlags flags, Regex filter, String commands, Context& context)
 {
-    auto& hooks = m_hooks[to_underlying(hook)];
-    hooks.emplace_back(new HookData{std::move(group), flags, std::move(filter), std::move(commands)});
+    std::unique_ptr<HookData> hook_data{new HookData{std::move(group), flags, std::move(filter), std::move(commands)}};
+    if (hook == Hook::ModuleLoaded)
+    {
+        const bool only_always = context.hooks_disabled();
+        auto& disabled_hooks = context.options()["disabled_hooks"].get<Regex>();
+
+        for (auto&& name : CommandManager::instance().loaded_modules())
+        {
+            MatchResults<const char*> captures;
+            if (hook_data->should_run(only_always, disabled_hooks, name, captures))
+            {
+                hook_data->exec(hook, name, context, captures);
+                if (hook_data->flags & HookFlags::Once)
+                    return;
+            }
+        }
+    }
+    m_hooks[to_underlying(hook)].push_back(std::move(hook_data));
 }
 
 void HookManager::remove_hooks(const Regex& regex)
@@ -62,21 +108,16 @@ CandidateList HookManager::complete_hook_group(StringView prefix, ByteCount pos_
 
 void HookManager::run_hook(Hook hook, StringView param, Context& context)
 {
-    auto& hook_list = m_hooks[to_underlying(hook)];
-
     const bool only_always = context.hooks_disabled();
     auto& disabled_hooks = context.options()["disabled_hooks"].get<Regex>();
 
     struct ToRun { HookData* hook; MatchResults<const char*> captures; };
     Vector<ToRun> hooks_to_run; // The m_hooks_trash vector ensure hooks wont die during this method
-    for (auto& hook : hook_list)
+    for (auto& hook : m_hooks[to_underlying(hook)])
     {
         MatchResults<const char*> captures;
-        if ((not only_always or (hook->flags & HookFlags::Always)) and
-            (hook->group.empty() or disabled_hooks.empty() or
-             not regex_match(hook->group.begin(), hook->group.end(), disabled_hooks))
-            and regex_match(param.begin(), param.end(), captures, hook->filter))
-            hooks_to_run.push_back({ hook.get(), std::move(captures) });
+        if (hook->should_run(only_always, disabled_hooks, param, captures))
+            hooks_to_run.push_back({hook.get(), std::move(captures)});
     }
 
     if (m_parent)
@@ -106,26 +147,12 @@ void HookManager::run_hook(Hook hook, StringView param, Context& context)
     {
         try
         {
-            if (debug_flags & DebugFlags::Hooks)
-                write_to_debug_buffer(format("hook {}({})/{}", hook_name, param, to_run.hook->group));
-
-            ScopedSetBool disable_history{context.history_disabled()};
-
-            EnvVarMap env_vars{ {"hook_param", param.str()} };
-            for (size_t i = 0; i < to_run.captures.size(); ++i)
-                env_vars.insert({format("hook_param_capture_{}", i),
-                                 {to_run.captures[i].first, to_run.captures[i].second}});
-            for (auto& c : to_run.hook->filter.impl()->named_captures)
-                env_vars.insert({format("hook_param_capture_{}", c.name),
-                                 {to_run.captures[c.index].first, to_run.captures[c.index].second}});
-
-            CommandManager::instance().execute(to_run.hook->commands, context,
-                                               { {}, std::move(env_vars) });
+            to_run.hook->exec(hook, param, context, to_run.captures);
 
             if (to_run.hook->flags & HookFlags::Once)
             {
-                auto it = find(hook_list, to_run.hook);
-                if (it != hook_list.end())
+                auto& hook_list = m_hooks[to_underlying(hook)];
+                if (auto it = find(hook_list, to_run.hook); it != hook_list.end())
                 {
                     m_hooks_trash.push_back(std::move(*it));
                     hook_list.erase(it);
diff --git a/src/hook_manager.hh b/src/hook_manager.hh
index 4b8a8913..24e88e1a 100644
--- a/src/hook_manager.hh
+++ b/src/hook_manager.hh
@@ -120,18 +120,18 @@ public:
     ~HookManager();
 
     void add_hook(Hook hook, String group, HookFlags flags,
-                  Regex filter, String commands);
+                  Regex filter, String commands, Context& context);
     void remove_hooks(const Regex& regex);
     CandidateList complete_hook_group(StringView prefix, ByteCount pos_in_token);
     void run_hook(Hook hook, StringView param, Context& context);
 
 private:
+    struct HookData;
+
     HookManager();
     // the only one allowed to construct a root hook manager
     friend class Scope;
 
-    struct HookData;
-
     SafePtr<HookManager> m_parent;
     Array<Vector<std::unique_ptr<HookData>, MemoryDomain::Hooks>, enum_desc(Meta::Type<Hook>{}).size()> m_hooks;
 
diff --git a/test/hooks/module-loaded/cmd b/test/hooks/module-loaded/cmd
new file mode 100644
index 00000000..80947651
--- /dev/null
+++ b/test/hooks/module-loaded/cmd
@@ -0,0 +1 @@
+"a<a-P>i<space><esc>
diff --git a/test/hooks/module-loaded/in b/test/hooks/module-loaded/in
new file mode 100644
index 00000000..8b137891
--- /dev/null
+++ b/test/hooks/module-loaded/in
@@ -0,0 +1 @@
+
diff --git a/test/hooks/module-loaded/out b/test/hooks/module-loaded/out
new file mode 100644
index 00000000..df4f2f61
--- /dev/null
+++ b/test/hooks/module-loaded/out
@@ -0,0 +1 @@
+ literal regex regex-once regex literal-late late-regex late-regex late-regex-once
diff --git a/test/hooks/module-loaded/rc b/test/hooks/module-loaded/rc
new file mode 100644
index 00000000..47ea4b50
--- /dev/null
+++ b/test/hooks/module-loaded/rc
@@ -0,0 +1,10 @@
+provide-module foo %{ }
+provide-module foobar %{ }
+hook global ModuleLoaded foo %{ set-register a %reg{a} literal }
+hook global ModuleLoaded f.* %{ set-register a %reg{a} regex }
+hook -once global ModuleLoaded f.* %{ set-register a %reg{a} regex-once }
+require-module foo
+require-module foobar
+hook global ModuleLoaded foo %{ set-register a %reg{a} literal-late }
+hook global ModuleLoaded f.* %{ set-register a %reg{a} late-regex }
+hook -once global ModuleLoaded f.* %{ set-register a %reg{a} late-regex-once }