refactor: MrDox uses C++ handlebars

This PR refactors the generators to use the C++ implementation of handlebars. Javascript helpers are loaded with duktape.

include/mrdox/Support/JavaScript.hpp

@@ -16,6 +16,7 @@
 #include <mrdox/Support/Error.hpp>
 #include <cstdlib>
 #include <string_view>
+#include <span>
 
 namespace clang {
 namespace mrdox {
@@ -42,7 +43,9 @@ enum class Type
     boolean,
     number,
     string,
-    object
+    object,
+    function,
+    array
 };
 
 //------------------------------------------------
@@ -120,12 +123,18 @@ class Scope
     MRDOX_DECL
     ~Scope();
 
-    /** Run a script.
+    /** Compile and run a script.
     */
     MRDOX_DECL
     Error
     script(std::string_view jsCode);
 
+    /** Compile a script and push results to stack.
+    */
+    MRDOX_DECL
+    Expected<Value>
+    compile(std::string_view jsCode);
+
     /** Return the global object.
     */
     MRDOX_DECL
@@ -170,10 +179,12 @@ class Value
     bool isString() const noexcept;
     bool isArray() const noexcept;
     bool isObject() const noexcept;
+    bool isFunction() const noexcept;
 
     std::string getString() const;
+    dom::Value getDom() const;
 
-void setlog();
+    void setlog();
 
     /** Call a function.
     */
@@ -184,6 +195,15 @@ void setlog();
         return callImpl({ dom::Value(std::forward<Args>(args))... });
     }
 
+    /** Call a function with variadic arguments.
+    */
+    template<class... Args>
+    Expected<Value>
+    apply(std::span<dom::Value> args) const
+    {
+        return callImpl(args);
+    }
+
     /** Call a function.
     */
     template<class... Args>
@@ -205,12 +225,30 @@ void setlog();
             { dom::Value(std::forward<Args>(args))... });
     }
 
+    /** Set a key.
+    */
+    MRDOX_DECL
+    void
+    set(
+        std::string_view key,
+        Value value) const;
+
+    /** Get a key.
+    */
+    MRDOX_DECL
+    Value
+    get(std::string_view key) const;
+
 private:
     MRDOX_DECL
     Expected<Value>
     callImpl(
         std::initializer_list<dom::Value> args) const;
 
+    MRDOX_DECL
+    Expected<Value>
+    callImpl(std::span<dom::Value> args) const;
+
     MRDOX_DECL
     Expected<Value>
     callPropImpl(
@@ -248,6 +286,11 @@ inline bool Value::isObject() const noexcept
     return type() == Type::object;
 }
 
+inline bool Value::isFunction() const noexcept
+{
+    return type() == Type::function;
+}
+
 } // js
 } // mrdox
 } // clang

share/mrdox/addons/generator/asciidoc/helpers/add.js

@@ -0,0 +1,3 @@
+function add(a, b) {
+    return a + b;
+}

src/lib/-HTML/Builder.cpp

@@ -38,112 +38,105 @@ Builder(
 
     Config const& config = corpus_.config;
 
-    js::Scope scope(ctx_);
-
-    scope.script(files::getFileText(
-        files::appendPath(
-            config->addonsDir, "js", "handlebars.js")
-        ).value()).maybeThrow();
-    auto Handlebars = scope.getGlobal("Handlebars").value();
-
-// VFALCO refactor this
-Handlebars.setlog();
-
-    // load templates
-#if 0
-    err = forEachFile(options_.template_dir,
-        [&](std::string_view fileName)
+    // load partials
+    std::string partialsPath = files::appendPath(
+        config->addonsDir, "generator", "html", "partials");
+    forEachFile(partialsPath,
+                [&](std::string_view pathName) -> Error
+    {
+        constexpr std::string_view ext = ".html.hbs";
+        if (!pathName.ends_with(ext))
         {
-            if(! fileName.ends_with(".html.hbs"))
-                return Error::success();
             return Error::success();
-        });
-#endif
-
-    Error err;
-
-    // load partials
-    forEachFile(
-        files::appendPath(config->addonsDir,
-            "generator", "html", "partials"),
-        [&](std::string_view pathName)
+        }
+        auto name = files::getFileName(pathName);
+        name.remove_suffix(ext.size());
+        auto text = files::getFileText(pathName);
+        if (!text)
         {
-            constexpr std::string_view ext = ".html.hbs";
-            if(! pathName.ends_with(ext))
-                return Error::success();
-            auto name = files::getFileName(pathName);
-            name.remove_suffix(ext.size());
-            auto text = files::getFileText(pathName);
-            if(! text)
-                return text.error();
-            return Handlebars.callProp(
-                "registerPartial", name, *text)
-                .error_or(Error::success());
-        }).maybeThrow();
+            return text.error();
+        }
+        hbs_.registerPartial(name, *text);
+        return Error::success();
+    }).maybeThrow();
 
     // load helpers
-#if 0
-    err = forEachFile(
-        files::appendPath(config->addonsDir,
-            "generator", "js", "helpers"),
-        [&](std::string_view pathName)
+    js::Scope scope(ctx_);
+    std::string helpersPath = files::appendPath(
+        config->addonsDir, "generator", "asciidoc", "helpers");
+    forEachFile(helpersPath,
+                [&](std::string_view pathName)
+    {
+        // Register JS helper function in the global object
+        constexpr std::string_view ext = ".js";
+        if (!pathName.ends_with(ext))
         {
-            constexpr std::string_view ext = ".js";
-            if(! pathName.ends_with(ext))
-                return Error::success();
-            auto name = files::getFileName(pathName);
-            name.remove_suffix(ext.size());
-            //Handlebars.callProp("registerHelper", name, *text);
-            auto err = ctx_.scriptFromFile(pathName);
             return Error::success();
-        }).maybeThrow();
-#endif
-
-    scope.script(fmt::format(
-        R"(Handlebars.registerHelper(
-            'is_multipage', function()
-        {{
-            return {};
-        }});
-        )", config->multiPage)).maybeThrow();
-
-    scope.script(R"(
-        Handlebars.registerHelper(
-            'to_string', function(context, depth)
-        {
-            return JSON.stringify(context, null, 2);
-        });
-
-        Handlebars.registerHelper(
-            'eq', function(a, b)
+        }
+        auto name = files::getFileName(pathName);
+        name.remove_suffix(ext.size());
+        auto text = files::getFileText(pathName);
+        if (!text)
         {
-            return a === b;
-        });
-
-        Handlebars.registerHelper(
-            'neq', function(a, b)
+            return text.error();
+        }
+        auto JSFn = scope.compile(*text);
+        if (!JSFn)
         {
-            return a !== b;
-        });
-
-        Handlebars.registerHelper(
-            'not', function(a)
-        {
-            return ! a;
-        });
-
-        Handlebars.registerHelper(
-            'or', function(a, b)
+            return JSFn.error();
+        }
+        scope.getGlobalObject().set(name, *JSFn);
+
+        // Register C++ helper that retrieves the helper
+        // from the global object, converts the arguments,
+        // and invokes the JS function.
+        hbs_.registerHelper(name, dom::makeVariadicInvocable(
+                                      [this, name=std::string(name)](
+                                          dom::Array const& args) -> Expected<dom::Value>
         {
-            return a || b;
-        });
-
-        Handlebars.registerHelper(
-            'and', function(a, b)
-        {
-            return a && b;
-        });
-    )").maybeThrow();
+            // Get function from global scope
+            js::Scope scope(ctx_);
+            js::Value fn = scope.getGlobalObject().get(name);
+            if (fn.isUndefined())
+            {
+                return Unexpected(Error("helper not found"));
+            }
+            if (!fn.isFunction())
+            {
+                return Unexpected(Error("helper is not a function"));
+            }
+
+            // Call function
+            std::vector<dom::Value> arg_span;
+            arg_span.reserve(args.size());
+            for (auto const& arg : args)
+            {
+                arg_span.push_back(arg);
+            }
+            auto result = fn.apply(arg_span);
+            if (!result)
+            {
+                return dom::Kind::Undefined;
+            }
+
+            // Convert result to dom::Value
+            return result->getDom();
+        }));
+        return Error::success();
+    }).maybeThrow();
+    hbs_.registerHelper(
+        "is_multipage",
+        dom::makeInvocable([res = config->multiPage]() -> Expected<dom::Value> {
+        return res;
+    }));
+    helpers::registerAntoraHelpers(hbs_);
+    hbs_.registerHelper("neq", dom::makeVariadicInvocable(helpers::ne_fn));
+    hbs_.registerHelper(
+        "to_string",
+        dom::makeInvocable(
+            [](dom::Value const& context) -> Expected<dom::Value> {
+        return dom::JSON::stringify(context);
+    }));
 }
 
 //------------------------------------------------
@@ -157,18 +150,23 @@ callTemplate(
     Config const& config = corpus_.config;
 
     js::Scope scope(ctx_);
+
+
     auto Handlebars = scope.getGlobal("Handlebars");
     auto layoutDir = files::appendPath(config->addonsDir,
             "generator", "html", "layouts");
     auto pathName = files::appendPath(layoutDir, name);
     MRDOX_TRY(auto fileText, files::getFileText(pathName));
-    dom::Object options;
-    options.set("allowProtoPropertiesByDefault", true);
-    // VFALCO This makes Proxy objects stop working
-    //options.set("allowProtoMethodsByDefault", true);
-    MRDOX_TRY(auto templateFn, Handlebars->callProp("compile", fileText, options));
-    MRDOX_TRY(auto result, templateFn.call(context, options));
-    return result.getString();
+    HandlebarsOptions options;
+    options.noEscape = true;
+
+    Expected<std::string, HandlebarsError> exp =
+        hbs_.try_render(fileText, context, options);
+    if (!exp)
+    {
+        return Unexpected(Error(exp.error().what()));
+    }
+    return *exp;
 }
 
 Expected<std::string>

src/lib/-HTML/Builder.hpp

@@ -15,6 +15,7 @@
 #include "lib/Support/Radix.hpp"
 #include <mrdox/Metadata/DomMetadata.hpp>
 #include <mrdox/Support/Error.hpp>
+#include <mrdox/Support/Handlebars.hpp>
 #include <mrdox/Support/JavaScript.hpp>
 #include <ostream>
 
@@ -33,6 +34,7 @@ class Builder
     Corpus const& corpus_;
     Options options_;
     js::Context ctx_;
+    Handlebars hbs_;
 
 public:
     Builder(

src/lib/-adoc/AdocGenerator.cpp

@@ -103,13 +103,13 @@ buildOne(
         });
     errors = ex->wait();
     if(! errors.empty())
-        return Error(errors);
+        return {errors};
 
     SinglePageVisitor visitor(*ex, corpus, os);
     visitor(corpus.globalNamespace());
     errors = ex->wait();
     if(! errors.empty())
-        return Error(errors);
+        return {errors};
 
     ex->async(
         [&os](Builder& builder)
@@ -119,7 +119,7 @@ buildOne(
         });
     errors = ex->wait();
     if(! errors.empty())
-        return Error(errors);
+        return {errors};
 
     return Error::success();
 }