JSSpecCompiler: Provide an adequate command line interface

Author: https://github.com/DanShaders
Commit: https://github.com/SerenityOS/serenity/commit/6ed069ea8d
Pull-request: https://github.com/SerenityOS/serenity/pull/21296
Reviewed-by: https://github.com/ADKaster

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/CompilationPipeline.h

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2023, Dan Klishch <danilklishch@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Function.h>
+#include <AK/StringView.h>
+
+#include "Forward.h"
+
+namespace JSSpecCompiler {
+
+class CompilationStep {
+public:
+    CompilationStep(StringView name)
+        : m_name(name)
+    {
+    }
+
+    virtual ~CompilationStep() = default;
+    virtual void run(TranslationUnitRef translation_unit) = 0;
+
+    StringView name() const { return m_name; }
+
+private:
+    StringView m_name;
+};
+
+class NonOwningCompilationStep : public CompilationStep {
+public:
+    template<typename Func>
+    NonOwningCompilationStep(StringView name, Func&& func)
+        : CompilationStep(name)
+        , m_func(func)
+    {
+    }
+
+    void run(TranslationUnitRef translation_unit) override { m_func(translation_unit); }
+
+private:
+    AK::Function<void(TranslationUnitRef)> m_func;
+};
+
+}

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/Compiler/Passes/FunctionCallCanonicalizationPass.h

@@ -17,6 +17,8 @@ namespace JSSpecCompiler {
 // `f(a, b, c, d)` as `f "function_call_operator" (a, (b, (c, d))))`.
 class FunctionCallCanonicalizationPass : public GenericASTPass {
 public:
+    inline static constexpr StringView name = "function-call-canonicalization"sv;
+
     using GenericASTPass::GenericASTPass;
 
 protected:

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/Compiler/Passes/IfBranchMergingPass.h

@@ -24,6 +24,8 @@ namespace JSSpecCompiler {
 // ```
 class IfBranchMergingPass : public GenericASTPass {
 public:
+    inline static constexpr StringView name = "if-branch-merging"sv;
+
     using GenericASTPass::GenericASTPass;
 
 protected:

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/Compiler/Passes/ReferenceResolvingPass.h

@@ -14,6 +14,8 @@ namespace JSSpecCompiler {
 // UnresolvedReference nodes with either SlotName, Variable, or FunctionPointer nodes.
 class ReferenceResolvingPass : public GenericASTPass {
 public:
+    inline static constexpr StringView name = "reference-resolving"sv;
+
     using GenericASTPass::GenericASTPass;
 
 protected:

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/Function.h

@@ -18,6 +18,7 @@ namespace JSSpecCompiler {
 struct TranslationUnit {
     FunctionDefinitionRef adopt_function(NonnullRefPtr<FunctionDefinition>&& function);
 
+    StringView filename;
     Vector<NonnullRefPtr<FunctionDefinition>> function_definitions;
     HashMap<StringView, FunctionPointerRef> function_index;
 };

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/Parser/CppASTConverter.cpp

@@ -4,8 +4,10 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
-#include "Parser/CppASTConverter.h"
+#include <LibCore/File.h>
+
 #include "Function.h"
+#include "Parser/CppASTConverter.h"
 #include "Parser/SpecParser.h"
 
 namespace JSSpecCompiler {
@@ -219,4 +221,32 @@ Tree CppASTConverter::as_possibly_empty_tree(Cpp::Statement const* statement)
     return make_ref_counted<TreeList>(Vector<Tree> {});
 }
 
+CppParsingStep::CppParsingStep()
+    : CompilationStep("parser"sv)
+{
+}
+
+CppParsingStep::~CppParsingStep() = default;
+
+void CppParsingStep::run(TranslationUnitRef translation_unit)
+{
+    auto filename = translation_unit->filename;
+
+    auto file = Core::File::open_file_or_standard_stream(filename, Core::File::OpenMode::Read).release_value_but_fixme_should_propagate_errors();
+    m_input = file->read_until_eof().release_value_but_fixme_should_propagate_errors();
+
+    Cpp::Preprocessor preprocessor { filename, m_input };
+    m_parser = adopt_own_if_nonnull(new Cpp::Parser { preprocessor.process_and_lex(), filename });
+
+    auto cpp_translation_unit = m_parser->parse();
+    VERIFY(m_parser->errors().is_empty());
+
+    for (auto const& declaration : cpp_translation_unit->declarations()) {
+        if (declaration->is_function()) {
+            auto const* cpp_function = AK::verify_cast<Cpp::FunctionDeclaration>(declaration.ptr());
+            translation_unit->adopt_function(CppASTConverter(cpp_function).convert());
+        }
+    }
+}
+
 }

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/Parser/CppASTConverter.h

@@ -6,9 +6,11 @@
 
 #pragma once
 
+#include <AK/OwnPtr.h>
 #include <LibCpp/AST.h>
+#include <LibCpp/Parser.h>
 
-#include "Forward.h"
+#include "CompilationPipeline.h"
 
 namespace JSSpecCompiler {
 
@@ -31,4 +33,16 @@ private:
     RefPtr<Cpp::FunctionDeclaration> m_function;
 };
 
+class CppParsingStep : public CompilationStep {
+public:
+    CppParsingStep();
+    ~CppParsingStep();
+
+    void run(TranslationUnitRef translation_unit) override;
+
+private:
+    OwnPtr<Cpp::Parser> m_parser;
+    ByteBuffer m_input;
+};
+
 }

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/Parser/SpecParser.cpp

@@ -5,7 +5,10 @@
  */
 
 #include <AK/NonnullOwnPtr.h>
+#include <LibCore/File.h>
+#include <LibXML/Parser/Parser.h>
 
+#include "Function.h"
 #include "Parser/Lexer.h"
 #include "Parser/SpecParser.h"
 #include "Parser/TextParser.h"
@@ -173,4 +176,31 @@ ParseErrorOr<void> SpecFunction::parse_definition(XML::Node const* element)
     return {};
 }
 
+SpecParsingStep::SpecParsingStep()
+    : CompilationStep("parser"sv)
+{
+}
+
+SpecParsingStep::~SpecParsingStep() = default;
+
+void SpecParsingStep::run(TranslationUnitRef translation_unit)
+{
+    auto filename = translation_unit->filename;
+
+    auto file = Core::File::open_file_or_standard_stream(filename, Core::File::OpenMode::Read).release_value_but_fixme_should_propagate_errors();
+    m_input = file->read_until_eof().release_value_but_fixme_should_propagate_errors();
+
+    XML::Parser parser { m_input };
+    auto document = parser.parse().release_value_but_fixme_should_propagate_errors();
+    m_document = AK::adopt_own_if_nonnull(new XML::Document(move(document)));
+
+    auto spec_function = SpecFunction::create(&m_document->root()).release_value_but_fixme_should_propagate_errors();
+
+    auto* function = translation_unit->adopt_function(
+        make_ref_counted<FunctionDefinition>(spec_function.m_name, spec_function.m_algorithm.m_tree));
+
+    for (auto const& argument : spec_function.m_arguments)
+        function->m_local_variables.set(argument.name, make_ref_counted<VariableDeclaration>(argument.name));
+}
+
 }

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/Parser/SpecParser.h

@@ -6,7 +6,10 @@
 
 #pragma once
 
+#include <AK/OwnPtr.h>
+
 #include "AST/AST.h"
+#include "CompilationPipeline.h"
 #include "Forward.h"
 #include "Parser/ParseError.h"
 #include "Parser/Token.h"
@@ -58,4 +61,16 @@ public:
     Algorithm m_algorithm;
 };
 
+class SpecParsingStep : public CompilationStep {
+public:
+    SpecParsingStep();
+    ~SpecParsingStep();
+
+    void run(TranslationUnitRef translation_unit) override;
+
+private:
+    OwnPtr<XML::Document> m_document;
+    ByteBuffer m_input;
+};
+
 }

Meta/Lagom/Tools/CodeGenerators/JSSpecCompiler/main.cpp

@@ -5,21 +5,96 @@
  */
 
 #include <AK/Format.h>
-#include <LibCore/File.h>
+#include <LibCore/ArgsParser.h>
 #include <LibMain/Main.h>
-#include <LibXML/Parser/Parser.h>
 
 #include "Compiler/Passes/FunctionCallCanonicalizationPass.h"
 #include "Compiler/Passes/IfBranchMergingPass.h"
 #include "Compiler/Passes/ReferenceResolvingPass.h"
 #include "Function.h"
+#include "Parser/CppASTConverter.h"
 #include "Parser/SpecParser.h"
 
-ErrorOr<int> serenity_main(Main::Arguments)
+using namespace JSSpecCompiler;
+
+class CompilationPipeline {
+public:
+    template<typename T>
+    void add_compilation_pass()
+    {
+        auto func = +[](TranslationUnitRef translation_unit) {
+            T { translation_unit }.run();
+        };
+        add_step(adopt_own_if_nonnull(new NonOwningCompilationStep(T::name, func)));
+    }
+
+    template<typename T>
+    void for_each_step_in(StringView pass_list, T&& func)
+    {
+        HashTable<StringView> selected_steps;
+        for (auto pass : pass_list.split_view(',')) {
+            if (pass == "all") {
+                for (auto const& step : m_pipeline)
+                    selected_steps.set(step->name());
+            } else if (pass == "last") {
+                selected_steps.set(m_pipeline.last()->name());
+            } else if (pass.starts_with('-')) {
+                VERIFY(selected_steps.remove(pass.substring_view(1)));
+            } else {
+                selected_steps.set(pass);
+            }
+        }
+
+        for (auto& step : m_pipeline)
+            if (selected_steps.contains(step->name()))
+                func(step);
+    }
+
+    void add_step(OwnPtr<CompilationStep>&& step)
+    {
+        m_pipeline.append(move(step));
+    }
+
+    auto const& pipeline() const { return m_pipeline; }
+
+private:
+    Vector<OwnPtr<CompilationStep>> m_pipeline;
+};
+
+ErrorOr<int> serenity_main(Main::Arguments arguments)
 {
-    using namespace JSSpecCompiler;
+    Core::ArgsParser args_parser;
+
+    StringView filename;
+    args_parser.add_positional_argument(filename, "File to compile", "file");
+
+    constexpr StringView language_spec = "spec"sv;
+    constexpr StringView language_cpp = "c++"sv;
+    StringView language = language_spec;
+    args_parser.add_option(Core::ArgsParser::Option {
+        .argument_mode = Core::ArgsParser::OptionArgumentMode::Optional,
+        .help_string = "Specify the language of the input file.",
+        .short_name = 'x',
+        .value_name = "{c++|spec}",
+        .accept_value = [&](StringView value) {
+            language = value;
+            return language.is_one_of(language_spec, language_cpp);
+        },
+    });
+
+    args_parser.parse(arguments);
+
+    CompilationPipeline pipeline;
+    if (language == language_cpp)
+        pipeline.add_step(adopt_own_if_nonnull(new CppParsingStep()));
+    else
+        pipeline.add_step(adopt_own_if_nonnull(new SpecParsingStep()));
+    pipeline.add_compilation_pass<FunctionCallCanonicalizationPass>();
+    pipeline.add_compilation_pass<IfBranchMergingPass>();
+    pipeline.add_compilation_pass<ReferenceResolvingPass>();
 
     TranslationUnit translation_unit;
+    translation_unit.filename = filename;
 
     // Functions referenced in DifferenceISODate
     // TODO: This is here just for testing. In a long run, we need some place, which is not
@@ -33,33 +108,8 @@ ErrorOr<int> serenity_main(Main::Arguments)
     functions.set("truncate"sv, make_ref_counted<FunctionPointer>("truncate"sv));
     functions.set("remainder"sv, make_ref_counted<FunctionPointer>("remainder"sv));
 
-    auto input = TRY(TRY(Core::File::standard_input())->read_until_eof());
-    XML::Parser parser { StringView(input.bytes()) };
+    for (auto const& step : pipeline.pipeline())
+        step->run(&translation_unit);
 
-    auto maybe_document = parser.parse();
-    if (maybe_document.is_error()) {
-        outln("{}", maybe_document.error());
-        return 1;
-    }
-    auto document = maybe_document.release_value();
-
-    auto maybe_function = JSSpecCompiler::SpecFunction::create(&document.root());
-    if (maybe_function.is_error()) {
-        outln("{}", maybe_function.error()->to_string());
-        return 1;
-    }
-    auto spec_function = maybe_function.value();
-
-    auto* function = translation_unit.adopt_function(
-        make_ref_counted<FunctionDefinition>(spec_function.m_name, spec_function.m_algorithm.m_tree));
-
-    for (auto const& argument : spec_function.m_arguments)
-        function->m_local_variables.set(argument.name, make_ref_counted<VariableDeclaration>(argument.name));
-
-    FunctionCallCanonicalizationPass(&translation_unit).run();
-    IfBranchMergingPass(&translation_unit).run();
-    ReferenceResolvingPass(&translation_unit).run();
-
-    out("{}", function->m_ast);
     return 0;
 }