Feature: Lute Config and Module Resolvers

lute/luau/CMakeLists.txt

@@ -1,14 +1,18 @@
 add_library(Lute.Luau STATIC)
 
 target_sources(Lute.Luau PRIVATE
+    include/lute/configresolver.h
     include/lute/luau.h
+    include/lute/moduleresolver.h
     include/lute/resolverequire.h
 
+    src/configresolver.cpp
     src/luau.cpp
+    src/moduleresolver.cpp
     src/resolverequire.cpp
 )
 
 target_compile_features(Lute.Luau PUBLIC cxx_std_17)
 target_include_directories(Lute.Luau PUBLIC "include" ${LIBUV_INCLUDE_DIR})
-target_link_libraries(Lute.Luau PRIVATE Lute.Require Lute.Runtime uv_a Luau.Analysis Luau.Ast Luau.Compiler Luau.Require Luau.VM)
+target_link_libraries(Lute.Luau PRIVATE Lute.Require Lute.Runtime uv_a Luau.Analysis Luau.Ast Luau.Compiler Luau.CLI.lib Luau.Require Luau.VM)
 target_compile_options(Lute.Luau PRIVATE ${LUTE_OPTIONS})

lute/luau/include/lute/configresolver.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include "Luau/Config.h"
+
+namespace Luau
+{
+
+// Based on LuteConfigResolver in tc.cpp.
+struct LuteConfigResolver : Luau::ConfigResolver
+{
+    Luau::Config defaultConfig;
+    mutable std::unordered_map<std::string, Luau::Config> configCache;
+    mutable std::vector<std::pair<std::string, std::string>> configErrors;
+
+    LuteConfigResolver(Luau::Mode mode);
+
+    const Luau::Config& getConfig(const Luau::ModuleName& name) const override;
+
+    const Luau::Config& readConfigRec(const std::string& path) const;
+};
+
+} // namespace Luau

lute/luau/include/lute/moduleresolver.h

@@ -0,0 +1,19 @@
+#pragma once
+
+#include "Luau/FileResolver.h"
+
+namespace Luau
+{
+
+// Based on CliFileResolver in Analyze.cpp.
+struct LuteModuleResolver : Luau::FileResolver
+{
+    LuteModuleResolver() = default;
+
+    std::optional<Luau::SourceCode> readSource(const Luau::ModuleName& name) override;
+
+    // We are currently resolving modules and requires only, and will add support for Roblox globals / types in a subsequent PR.
+    std::optional<Luau::ModuleInfo> resolveModule(const Luau::ModuleInfo* context, Luau::AstExpr* node) override;
+};
+
+} // namespace Luau

lute/luau/src/configresolver.cpp

@@ -0,0 +1,79 @@
+#include "lute/configresolver.h"
+
+#include "Luau/LuauConfig.h"
+#include "Luau/FileUtils.h"
+#include "Luau/StringUtils.h"
+
+namespace Luau
+{
+
+LuteConfigResolver::LuteConfigResolver(Luau::Mode mode)
+{
+    defaultConfig.mode = mode;
+}
+
+const Luau::Config& LuteConfigResolver::getConfig(const Luau::ModuleName& name) const
+{
+    std::optional<std::string> path = getParentPath(name);
+    if (!path)
+        return defaultConfig;
+
+    return readConfigRec(*path);
+}
+
+const Luau::Config& LuteConfigResolver::readConfigRec(const std::string& path) const
+{
+    auto it = configCache.find(path);
+    if (it != configCache.end())
+        return it->second;
+
+    std::optional<std::string> parent = getParentPath(path);
+    Luau::Config result = parent ? readConfigRec(*parent) : defaultConfig;
+
+    std::optional<std::string> configPath = joinPaths(path, Luau::kConfigName);
+    if (!isFile(*configPath))
+        configPath = std::nullopt;
+
+    std::optional<std::string> luauConfigPath = joinPaths(path, Luau::kLuauConfigName);
+    if (!isFile(*luauConfigPath))
+        luauConfigPath = std::nullopt;
+
+    if (configPath && luauConfigPath)
+    {
+        std::string ambiguousError = format("Both %s and %s files exist", Luau::kConfigName, Luau::kLuauConfigName);
+        configErrors.emplace_back(*configPath, std::move(ambiguousError));
+    }
+    else if (configPath)
+    {
+        if (std::optional<std::string> contents = readFile(*configPath))
+        {
+            Luau::ConfigOptions::AliasOptions aliasOpts;
+            aliasOpts.configLocation = *configPath;
+            aliasOpts.overwriteAliases = true;
+
+            Luau::ConfigOptions opts;
+            opts.aliasOptions = std::move(aliasOpts);
+
+            std::optional<std::string> error = Luau::parseConfig(*contents, result, opts);
+            if (error)
+                configErrors.emplace_back(*configPath, *error);
+        }
+    }
+    else if (luauConfigPath)
+    {
+        if (std::optional<std::string> contents = readFile(*luauConfigPath))
+        {
+            Luau::ConfigOptions::AliasOptions aliasOpts;
+            aliasOpts.configLocation = *luauConfigPath;
+            aliasOpts.overwriteAliases = true;
+
+            std::optional<std::string> error = Luau::extractLuauConfig(*contents, result, aliasOpts, Luau::InterruptCallbacks{});
+            if (error)
+                configErrors.emplace_back(*luauConfigPath, *error);
+        }
+    }
+
+    return configCache[path] = result;
+}
+
+} // namespace Luau

lute/luau/src/moduleresolver.cpp

@@ -0,0 +1,40 @@
+#include "lute/moduleresolver.h"
+
+#include "Luau/Ast.h"
+#include "Luau/FileUtils.h"
+
+#include "lute/resolverequire.h"
+
+namespace Luau
+{
+
+std::optional<Luau::SourceCode> LuteModuleResolver::readSource(const Luau::ModuleName& name)
+{
+    if (std::optional<std::string> source = readFile(name))
+        return Luau::SourceCode{*source, Luau::SourceCode::Module};
+    return std::nullopt;
+}
+
+// We are currently resolving modules and requires only, and will add support for Roblox globals / types in a subsequent PR.
+std::optional<Luau::ModuleInfo> LuteModuleResolver::resolveModule(const Luau::ModuleInfo* context, Luau::AstExpr* node)
+{
+    if (auto expr = node->as<Luau::AstExprConstantString>())
+    {
+        std::string requirePath(expr->value.data, expr->value.size);
+
+        std::string error;
+        std::string requirerChunkname = "@" + context->name;
+        std::optional<std::string> absolutePath = resolveRequire(requirePath, std::move(requirerChunkname), &error);
+        if (!absolutePath)
+        {
+            printf("Failed to resolve require: %s\n", error.c_str());
+            return std::nullopt;
+        }
+
+        return Luau::ModuleInfo{*absolutePath};
+    }
+
+    return std::nullopt;
+}
+
+} // namespace Luau

tests/CMakeLists.txt

@@ -9,14 +9,15 @@ target_sources(Lute.Test PRIVATE
     src/luteprojectroot.h
     src/luteprojectroot.cpp
 
+    src/compile.test.cpp
+    src/configresolver.test.cpp
     src/modulepath.test.cpp
+    src/moduleresolver.test.cpp
     src/require.test.cpp
-    src/stdsystem.test.cpp
     src/staticrequires.test.cpp
-    src/stdsystem.test.cpp
-    src/compile.test.cpp)
+    src/stdsystem.test.cpp)
 
 set_target_properties(Lute.Test PROPERTIES OUTPUT_NAME lute-tests)
 target_compile_features(Lute.Test PUBLIC cxx_std_17)
-target_link_libraries(Lute.Test PRIVATE Lute.CLI.lib Lute.Require Lute.Runtime Luau.CLI.lib Luau.Compiler Luau.VM)
+target_link_libraries(Lute.Test PRIVATE Lute.CLI.lib Lute.Luau Lute.Require Lute.Runtime Luau.CLI.lib Luau.Analysis Luau.Compiler Luau.VM)
 target_compile_options(Lute.Test PRIVATE ${LUTE_OPTIONS})

tests/src/configresolver.test.cpp

@@ -0,0 +1,31 @@
+// Tests for configuration resolver inheritance and ambiguity.
+#include "doctest.h"
+#include "luteprojectroot.h"
+
+#include "lute/configresolver.h"
+
+#include "Luau/FileUtils.h"
+
+TEST_CASE("configresolver")
+{
+    std::string root = getLuteProjectRootAbsolute();
+    std::string baseDir = joinPaths(root, "tests/src/resolver");
+    std::string file = joinPaths(baseDir, "mainmodule.luau");
+
+    // There is a .luaurc in tests/src/resolver; verify resolver reads it without crashing
+    Luau::LuteConfigResolver configResolver(Luau::Mode::Nonstrict);
+    const Luau::Config& cfg = configResolver.getConfig(file);
+
+    // check that mode was set to strict per .luaurc
+    CHECK(cfg.mode == Luau::Mode::Strict);
+
+    // check the alias root was set
+    const Luau::Config::AliasInfo* aliasInfo = cfg.aliases.find("root");
+    CHECK(aliasInfo != nullptr);
+    CHECK(aliasInfo->value == "./");
+
+    // run readConfigRec on parent directory to verify inheritance
+    const Luau::Config& parentCfg = configResolver.readConfigRec(baseDir);
+    // mode should be the same as child since no override
+    CHECK(parentCfg.mode == Luau::Mode::Strict);
+}

tests/src/moduleresolver.test.cpp

@@ -0,0 +1,24 @@
+// Simplified tests for module resolver functionality using public APIs.
+#include "doctest.h"
+#include "luteprojectroot.h"
+
+#include "Luau/Ast.h"
+#include "Luau/FileUtils.h"
+
+#include "lute/moduleresolver.h"
+#include "lute/resolverequire.h"
+
+#include <string>
+
+TEST_CASE("moduleresolver_read_source")
+{
+    std::string root = getLuteProjectRootAbsolute();
+    std::string file = joinPaths(root, "tests/src/resolver/mainmodule.luau");
+    Luau::LuteModuleResolver resolver;
+    auto source = resolver.readSource(file);
+    REQUIRE(source);
+    CHECK(source->type == Luau::SourceCode::Module);
+    CHECK(source->source.find("require") != std::string::npos);
+}
+
+// TODO: add tests for resolveModule

tests/src/resolver/.luaurc

@@ -0,0 +1,6 @@
+{
+    "languageMode": "strict",
+    "aliases": {
+        "root": "./"
+    }
+}

tests/src/resolver/mainmodule.luau

@@ -0,0 +1,27 @@
+local types = require("@root/types")
+local tableext = require("@std/tableext")
+
+local testFilter: { [string]: number } = {
+	["a"] = 1,
+	["b"] = 2,
+}
+
+local a = {}
+type tb = tableext.dictionary<number>
+
+function a._a(a: number)
+	return function(s: string): types.test
+		return types(s, a)
+	end
+end
+
+a._b = tableext.map(testFilter, function(value)
+	return tostring(value)
+end)
+
+a._metadata = {
+	key = -1,
+	id = "nice",
+}
+
+return a

tests/src/resolver/types.luau

@@ -0,0 +1,7 @@
+export type test = { [string]: number }
+
+return function(s: string, n: number): test
+	return {
+		[s] = n,
+	}
+end