Merge branch 'feature/config-info' into develop

catalog.json

@@ -1,5 +1,16 @@
 {
   "packages": {
+    "ctre": {
+      "2.7.0": {
+        "depends": {},
+        "description": "A compile-time PCRE (almost) compatible regular expression matcher",
+        "git": {
+          "auto-lib": "hanickadot/ctre",
+          "ref": "v2.7",
+          "url": "https://github.com/hanickadot/compile-time-regular-expressions.git"
+        }
+      }
+    },
     "fmt": {
       "0.10.0": {
         "depends": {},

library.dds

@@ -10,3 +10,4 @@ Uses: semver/semver
 Uses: vob/semester
 Uses: pubgrub/pubgrub
 Uses: vob/json5
+Uses: hanickadot/ctre

library.jsonc

@@ -12,5 +12,6 @@
         "pubgrub/pubgrub",
         "vob/json5",
         "vob/semester",
+        "hanickadot/ctre",
     ]
 }

package.dds

@@ -12,5 +12,6 @@ Depends: semver 0.2.1
 Depends: pubgrub 0.2.0
 Depends: vob-json5 0.1.5
 Depends: vob-semester 0.1.0
+Depends: ctre 2.7.0
 
 Test-Driver: Catch-Main

package.jsonc

@@ -13,7 +13,8 @@
         "semver": "0.2.1",
         "pubgrub": "0.2.0",
         "vob-json5": "0.1.5",
-        "vob-semester": "0.1.0"
+        "vob-semester": "0.1.0",
+        "ctre": "2.7.0",
     },
     "test_driver": "Catch-Main"
 }

src/dds/build/builder.cpp

@@ -150,9 +150,13 @@ prepare_ureqs(const build_plan& plan, const toolchain& toolchain, path_ref out_r
             lib_reqs.include_paths.push_back(lib.library_().public_include_dir());
             lib_reqs.uses  = lib.library_().manifest().uses;
             lib_reqs.links = lib.library_().manifest().links;
-            if (const auto& arc = lib.create_archive()) {
+            if (const auto& arc = lib.archive_plan()) {
                 lib_reqs.linkable_path = out_root / arc->calc_archive_file_path(toolchain);
             }
+            auto gen_incdir_opt = lib.generated_include_dir();
+            if (gen_incdir_opt) {
+                lib_reqs.include_paths.push_back(out_root / *gen_incdir_opt);
+            }
         }
     }
     return ureqs;
@@ -170,7 +174,7 @@ void write_lml(build_env_ref env, const library_plan& lib, path_ref lml_path) {
     for (auto&& link : lib.links()) {
         out << "Links: " << link.namespace_ << "/" << link.name << '\n';
     }
-    if (auto&& arc = lib.create_archive()) {
+    if (auto&& arc = lib.archive_plan()) {
         out << "Path: "
             << (env.output_root / arc->calc_archive_file_path(env.toolchain)).generic_string()
             << '\n';
@@ -225,6 +229,8 @@ void builder::build(const build_params& params) const {
         generate_compdb(plan, env);
     }
 
+    plan.render_all(env);
+
     dds::stopwatch sw;
     plan.compile_all(env, params.parallel_jobs);
     spdlog::info("Compilation completed in {:n}ms", sw.elapsed_ms().count());

src/dds/build/iter_compilations.hpp

@@ -24,12 +24,14 @@ inline auto iter_libraries(const build_plan& plan) {
  * Return a range iterating over ever file compilation defined in the given build plan
  */
 inline auto iter_compilations(const build_plan& plan) {
-    auto lib_compiles =                                                                        //
-        iter_libraries(plan)                                                                   //
-        | ranges::views::transform(&library_plan::create_archive)                              //
-        | ranges::views::filter([&](auto&& opt) { return bool(opt); })                         //
-        | ranges::views::transform([&](auto&& opt) -> auto& { return opt->compile_files(); })  //
-        | ranges::views::join                                                                  //
+    auto lib_compiles =                                                 //
+        iter_libraries(plan)                                            //
+        | ranges::views::transform(&library_plan::archive_plan)         //
+        | ranges::views::filter([&](auto&& opt) { return bool(opt); })  //
+        | ranges::views::transform([&](auto&& opt) -> auto& {
+              return opt->file_compilations();
+          })                   //
+        | ranges::views::join  //
         ;
 
     auto exe_compiles =                                                       //

src/dds/build/plan/archive.hpp

@@ -58,7 +58,7 @@ public:
     /**
      * Get the compilation plans for this library.
      */
-    auto& compile_files() const noexcept { return _compile_files; }
+    auto& file_compilations() const noexcept { return _compile_files; }
 
     /**
      * Perform the actual archive generation. Expects all compilations to have

src/dds/build/plan/compile_file.cpp

@@ -15,7 +15,13 @@ using namespace dds;
 compile_command_info compile_file_plan::generate_compile_command(build_env_ref env) const {
     compile_file_spec spec{_source.path, calc_object_file_path(env)};
     spec.enable_warnings = _rules.enable_warnings();
-    extend(spec.include_dirs, _rules.include_dirs());
+    for (auto dirpath : _rules.include_dirs()) {
+        if (!dirpath.is_absolute()) {
+            dirpath = env.output_root / dirpath;
+        }
+        dirpath = fs::weakly_canonical(dirpath);
+        spec.include_dirs.push_back(std::move(dirpath));
+    }
     for (const auto& use : _rules.uses()) {
         extend(spec.external_include_dirs, env.ureqs.include_paths(use));
     }
@@ -24,8 +30,7 @@ compile_command_info compile_file_plan::generate_compile_command(build_env_ref e
 }
 
 fs::path compile_file_plan::calc_object_file_path(const build_env& env) const noexcept {
-    // `relpath` is just the path from the root of the source directory to the source file.
-    auto relpath = fs::relative(_source.path, _source.basis_path);
+    auto relpath = _source.relative_path();
     // The full output directory is prefixed by `_subdir`
     auto ret = env.output_root / _subdir / relpath;
     ret.replace_filename(relpath.filename().string() + env.toolchain.object_suffix());

src/dds/build/plan/exe.cpp

@@ -25,11 +25,11 @@ void link_executable_plan::link(build_env_ref env, const library_plan& lib) cons
     for (const lm::usage& links : _links) {
         extend(spec.inputs, env.ureqs.link_paths(links));
     }
-    if (lib.create_archive()) {
+    if (lib.archive_plan()) {
         // The associated library has compiled components. Add the static library a as a linker
         // input
         spec.inputs.push_back(env.output_root
-                              / lib.create_archive()->calc_archive_file_path(env.toolchain));
+                              / lib.archive_plan()->calc_archive_file_path(env.toolchain));
     }
 
     // The main object should be a linker input, of course.

src/dds/build/plan/full.cpp

@@ -7,7 +7,9 @@
 #include <range/v3/view/concat.hpp>
 #include <range/v3/view/filter.hpp>
 #include <range/v3/view/join.hpp>
+#include <range/v3/view/repeat.hpp>
 #include <range/v3/view/transform.hpp>
+#include <range/v3/view/zip.hpp>
 
 #include <spdlog/spdlog.h>
 
@@ -72,8 +74,25 @@ bool parallel_run(Range&& rng, int n_jobs, Fn&& fn) {
     return exceptions.empty();
 }
 
+template <typename T, typename Range>
+decltype(auto) pair_up(T& left, Range& right) {
+    auto rep = ranges::view::repeat(left);
+    return ranges::view::zip(rep, right);
+}
+
 }  // namespace
 
+void build_plan::render_all(build_env_ref env) const {
+    auto templates = _packages                                                                    //
+        | ranges::view::transform(&package_plan::libraries)                                       //
+        | ranges::view::join                                                                      //
+        | ranges::view::transform([](const auto& lib) { return pair_up(lib, lib.templates()); })  //
+        | ranges::view::join;
+    for (const auto& [lib, tmpl] : templates) {
+        tmpl.render(env, lib.library_());
+    }
+}
+
 void build_plan::compile_all(const build_env& env, int njobs) const {
     auto okay = dds::compile_all(iter_compilations(*this), env, njobs);
     if (!okay) {
@@ -83,8 +102,8 @@ void build_plan::compile_all(const build_env& env, int njobs) const {
 
 void build_plan::archive_all(const build_env& env, int njobs) const {
     auto okay = parallel_run(iter_libraries(*this), njobs, [&](const library_plan& lib) {
-        if (lib.create_archive()) {
-            lib.create_archive()->archive(env);
+        if (lib.archive_plan()) {
+            lib.archive_plan()->archive(env);
         }
     });
     if (!okay) {

src/dds/build/plan/full.hpp

@@ -28,6 +28,10 @@ public:
      * All of the packages in this plan
      */
     auto& packages() const noexcept { return _packages; }
+    /**
+     * Render all config templates in the plan.
+     */
+    void render_all(const build_env& env) const;
     /**
      * Compile all files in the plan.
      */

src/dds/build/plan/library.cpp

@@ -7,9 +7,24 @@
 #include <range/v3/view/transform.hpp>
 
 #include <cassert>
+#include <string>
 
 using namespace dds;
 
+namespace {
+
+const std::string gen_dir_qual = "__dds/gen";
+
+fs::path rebase_gen_incdir(path_ref subdir) { return gen_dir_qual / subdir; }
+}  // namespace
+
+std::optional<fs::path> library_plan::generated_include_dir() const noexcept {
+    if (_templates.empty()) {
+        return std::nullopt;
+    }
+    return rebase_gen_incdir(output_subdirectory());
+}
+
 library_plan library_plan::create(const library_root&             lib,
                                   const library_build_params&     params,
                                   std::optional<std::string_view> qual_name_) {
@@ -17,6 +32,7 @@ library_plan library_plan::create(const library_root&             lib,
     std::vector<source_file> app_sources;
     std::vector<source_file> test_sources;
     std::vector<source_file> lib_sources;
+    std::vector<source_file> template_sources;
 
     auto qual_name = std::string(qual_name_.value_or(lib.manifest().name));
 
@@ -34,6 +50,8 @@ library_plan library_plan::create(const library_root&             lib,
                 app_sources.push_back(sfile);
             } else if (sfile.kind == source_kind::source) {
                 lib_sources.push_back(sfile);
+            } else if (sfile.kind == source_kind::header_template) {
+                template_sources.push_back(sfile);
             } else {
                 assert(sfile.kind == source_kind::header);
             }
@@ -45,6 +63,12 @@ library_plan library_plan::create(const library_root&             lib,
     compile_rules.enable_warnings() = params.enable_warnings;
     compile_rules.uses()            = lib.manifest().uses;
 
+    const auto codegen_subdir = rebase_gen_incdir(params.out_subdir);
+
+    if (!template_sources.empty()) {
+        compile_rules.include_dirs().push_back(codegen_subdir);
+    }
+
     // Convert the library sources into their respective file compilation plans.
     auto lib_compile_files =  //
         lib_sources           //
@@ -55,12 +79,12 @@ library_plan library_plan::create(const library_root&             lib,
 
     // If we have any compiled library files, generate a static library archive
     // for this library
-    std::optional<create_archive_plan> create_archive;
+    std::optional<create_archive_plan> archive_plan;
     if (!lib_compile_files.empty()) {
-        create_archive.emplace(lib.manifest().name,
-                               qual_name,
-                               params.out_subdir,
-                               std::move(lib_compile_files));
+        archive_plan.emplace(lib.manifest().name,
+                             qual_name,
+                             params.out_subdir,
+                             std::move(lib_compile_files));
     }
 
     // Collect the paths to linker inputs that should be used when generating executables for this
@@ -86,8 +110,7 @@ library_plan library_plan::create(const library_root&             lib,
         // Pick a subdir based on app/test
         const auto subdir_base = is_test ? params.out_subdir / "test" : params.out_subdir;
         // Put test/app executables in a further subdirectory based on the source file path
-        const auto subdir
-            = subdir_base / fs::relative(source.path.parent_path(), lib.src_source_root().path);
+        const auto subdir = subdir_base / source.relative_path().parent_path();
         // Pick compile rules based on app/test
         auto rules = is_test ? test_rules : compile_rules;
         // Pick input libs based on app/test
@@ -105,6 +128,16 @@ library_plan library_plan::create(const library_root&             lib,
         link_executables.emplace_back(std::move(exe));
     }
 
+    std::vector<render_template_plan> render_templates;
+    for (const auto& sf : template_sources) {
+        render_templates.emplace_back(sf, codegen_subdir);
+    }
+
     // Done!
-    return library_plan{lib, qual_name, std::move(create_archive), std::move(link_executables)};
+    return library_plan{lib,
+                        qual_name,
+                        params.out_subdir,
+                        std::move(archive_plan),
+                        std::move(link_executables),
+                        std::move(render_templates)};
 }

src/dds/build/plan/library.hpp

@@ -2,6 +2,7 @@
 
 #include <dds/build/plan/archive.hpp>
 #include <dds/build/plan/exe.hpp>
+#include <dds/build/plan/template.hpp>
 #include <dds/library/root.hpp>
 #include <dds/usage_reqs.hpp>
 #include <dds/util/fs.hpp>
@@ -56,10 +57,14 @@ class library_plan {
     library_root _lib;
     /// The qualified name of the library
     std::string _qual_name;
+    /// The library's subdirectory within the output directory
+    fs::path _subdir;
     /// The `create_archive_plan` for this library, if applicable
     std::optional<create_archive_plan> _create_archive;
     /// The executables that should be linked as part of this library's build
     std::vector<link_executable_plan> _link_exes;
+    /// The templates that must be rendered for this library
+    std::vector<render_template_plan> _templates;
 
 public:
     /**
@@ -70,12 +75,16 @@ public:
      */
     library_plan(library_root                       lib,
                  std::string_view                   qual_name,
+                 fs::path                           subdir,
                  std::optional<create_archive_plan> ar,
-                 std::vector<link_executable_plan>  exes)
+                 std::vector<link_executable_plan>  exes,
+                 std::vector<render_template_plan>  tmpls)
         : _lib(std::move(lib))
         , _qual_name(qual_name)
+        , _subdir(std::move(subdir))
         , _create_archive(std::move(ar))
-        , _link_exes(std::move(exes)) {}
+        , _link_exes(std::move(exes))
+        , _templates(std::move(tmpls)) {}
 
     /**
      * Get the underlying library object
@@ -89,6 +98,10 @@ public:
      * Get the qualified name of the library, as if for a libman usage requirement
      */
     auto& qualified_name() const noexcept { return _qual_name; }
+    /**
+     * The output subdirectory of this library plan
+     */
+    path_ref output_subdirectory() const noexcept { return _subdir; }
     /**
      * The directory that defines the source root of the library.
      */
@@ -97,7 +110,11 @@ public:
      * A `create_archive_plan` object, or `nullopt`, depending on if this library has compiled
      * components
      */
-    auto& create_archive() const noexcept { return _create_archive; }
+    auto& archive_plan() const noexcept { return _create_archive; }
+    /**
+     * The template rendering plans for this library.
+     */
+    auto& templates() const noexcept { return _templates; }
     /**
      * The executables that should be created by this library
      */
@@ -110,6 +127,12 @@ public:
      * The library identifiers that are linked by this library
      */
     auto& links() const noexcept { return _lib.manifest().links; }
+    /**
+     * The path to the directory that should be added for the #include search
+     * path for this library, relative to the build root. Returns `nullopt` if
+     * this library has no generated headers.
+     */
+    std::optional<fs::path> generated_include_dir() const noexcept;
 
     /**
      * Named constructor: Create a new `library_plan` automatically from some build-time parameters.
@@ -129,4 +152,4 @@ public:
                                std::optional<std::string_view> qual_name);
 };
 
-}  // namespace dds
+}  // namespace dds

src/dds/build/plan/template.cpp

@@ -0,0 +1,193 @@
+#include <dds/build/plan/template.hpp>
+
+#include <dds/error/errors.hpp>
+#include <dds/library/root.hpp>
+#include <dds/util/fs.hpp>
+#include <dds/util/string.hpp>
+
+#include <ctre.hpp>
+#include <semester/json.hpp>
+
+#include <string>
+#include <string_view>
+
+using namespace dds;
+
+using json_data = semester::basic_data<semester::json_traits<std::allocator<void>>>;
+
+namespace {
+
+static constexpr ctll::fixed_string IDENT_RE{"([_a-zA-Z]\\w*)(.*)"};
+
+std::string_view skip(std::string_view in) {
+    auto nspace_pos = in.find_first_not_of(" \t\n\r\f");
+    in              = in.substr(nspace_pos);
+    if (starts_with(in, "/*")) {
+        // It's a block comment. Find the block-end marker.
+        auto block_end = in.find("*/");
+        if (block_end == in.npos) {
+            throw_user_error<errc::template_error>("Unterminated block comment");
+        }
+        in = in.substr(block_end + 2);
+        // Recursively skip some more
+        return skip(in);
+    }
+    if (starts_with(in, "//")) {
+    more:
+        // It's a line comment. Find the next not-continued newline
+        auto cn_nl = in.find("\\\n");
+        auto nl    = in.find("\n");
+        if (cn_nl < nl) {
+            // The next newline is a continuation of the comment. Keep looking
+            in = in.substr(nl + 1);
+            goto more;
+        }
+        if (nl == in.npos) {
+            // We've reached the end. Okay.
+            return in.substr(nl);
+        }
+    }
+    // Not a comment, and not whitespace. Okay.
+    return in;
+}
+
+std::string stringify(const json_data& dat) {
+    if (dat.is_bool()) {
+        return dat.as_bool() ? "true" : "false";
+    } else if (dat.is_double()) {
+        return std::to_string(dat.as_double());
+    } else if (dat.is_null()) {
+        return "nullptr";
+    } else if (dat.is_string()) {
+        /// XXX: This probably isn't quite enough sanitization for edge cases.
+        auto str = dat.as_string();
+        str      = replace(str, "\n", "\\n");
+        str      = replace(str, "\"", "\\\"");
+        return "\"" + str + "\"";
+    } else {
+        throw_user_error<errc::template_error>("Cannot render un-stringable data type");
+    }
+}
+
+std::pair<std::string, std::string_view> eval_expr_tail(std::string_view in, const json_data& dat) {
+    in = skip(in);
+    if (starts_with(in, ".")) {
+        // Accessing a subproperty of the data
+        in.remove_prefix(1);
+        in = skip(in);
+        // We _must_ see an identifier
+        auto [is_ident, ident, tail] = ctre::match<IDENT_RE>(in);
+        if (!is_ident) {
+            throw_user_error<errc::template_error>("Expected identifier following dot `.`");
+        }
+        if (!dat.is_mapping()) {
+            throw_user_error<errc::template_error>("Cannot use dot `.` on non-mapping object");
+        }
+        auto& map   = dat.as_mapping();
+        auto  found = map.find(ident.to_view());
+        if (found == map.end()) {
+            throw_user_error<errc::template_error>("No subproperty '{}'", ident.to_view());
+        }
+        return eval_expr_tail(tail, found->second);
+    }
+    return {stringify(dat), in};
+}
+
+std::pair<std::string, std::string_view> eval_primary_expr(std::string_view in,
+                                                           const json_data& dat) {
+    in = skip(in);
+
+    if (in.empty()) {
+        throw_user_error<errc::template_error>("Expected primary expression");
+    }
+
+    if (in.front() == '(') {
+        in               = in.substr(1);
+        auto [ret, tail] = eval_primary_expr(in, dat);
+        if (!starts_with(tail, ")")) {
+            throw_user_error<errc::template_error>(
+                "Expected closing parenthesis `)` following expression");
+        }
+        return {ret, tail.substr(1)};
+    }
+
+    auto [is_ident, ident, tail_1] = ctre::match<IDENT_RE>(in);
+
+    if (is_ident) {
+        auto& map   = dat.as_mapping();
+        auto  found = map.find(ident.to_view());
+        if (found == map.end()) {
+            throw_user_error<errc::template_error>("Unknown top-level identifier '{}'",
+                                                   ident.to_view());
+        }
+
+        return eval_expr_tail(tail_1, found->second);
+    }
+
+    return {"nope", in};
+}
+
+std::string render_template(std::string_view tmpl, const library_root& lib) {
+    std::string      acc;
+    std::string_view MARKER_STRING = "__dds";
+
+    // Fill out a data structure that will be exposed to the template
+    json_data dat = json_data::mapping_type({
+        {
+            "lib",
+            json_data::mapping_type{
+                {"name", lib.manifest().name},
+                {"root", lib.path().string()},
+            },
+        },
+    });
+
+    while (!tmpl.empty()) {
+        // Find the next marker in the template string
+        auto next_marker = tmpl.find(MARKER_STRING);
+        if (next_marker == tmpl.npos) {
+            // We've reached the end of the template. Stop
+            acc.append(tmpl);
+            break;
+        }
+        // Append the string up to the next marker
+        acc.append(tmpl.substr(0, next_marker));
+        // Consume up to the next marker
+        tmpl                = tmpl.substr(next_marker + MARKER_STRING.size());
+        auto next_not_space = tmpl.find_first_not_of(" \t");
+        if (next_not_space == tmpl.npos || tmpl[next_not_space] != '(') {
+            throw_user_error<errc::template_error>(
+                "Expected `(` following `__dds` identifier in template file");
+        }
+
+        auto [inner, tail] = eval_primary_expr(tmpl, dat);
+        acc.append(inner);
+        tmpl = tail;
+    }
+
+    return acc;
+}
+
+}  // namespace
+
+void render_template_plan::render(build_env_ref env, const library_root& lib) const {
+    auto content = slurp_file(_source.path);
+
+    // Calculate the destination of the template rendering
+    auto dest = env.output_root / _subdir / _source.relative_path();
+    dest.replace_filename(dest.stem().stem().filename().string() + dest.extension().string());
+    fs::create_directories(dest.parent_path());
+
+    auto result = render_template(content, lib);
+    if (fs::is_regular_file(dest)) {
+        auto existing_content = slurp_file(dest);
+        if (result == existing_content) {
+            /// The content of the file has not changed. Do not write a file.
+            return;
+        }
+    }
+
+    auto ofile = open(dest, std::ios::binary | std::ios::out);
+    ofile << result;
+    ofile.close();  // Throw any exceptions while closing the file
+}

src/dds/build/plan/template.hpp

@@ -0,0 +1,38 @@
+#pragma once
+
+#include <dds/build/plan/base.hpp>
+#include <dds/source/file.hpp>
+
+#include <utility>
+
+namespace dds {
+
+class library_root;
+
+class render_template_plan {
+    /**
+     * The source file that defines the config template
+     */
+    source_file _source;
+    /**
+     * The subdirectory in which the template should be rendered.
+     */
+    fs::path _subdir;
+
+public:
+    /**
+     * Create a new instance
+     * @param sf The source file of the template
+     * @param subdir The subdirectort into which the template should render
+     */
+    render_template_plan(source_file sf, path_ref subdir)
+        : _source(std::move(sf))
+        , _subdir(subdir) {}
+
+    /**
+     * Render the template into its output directory
+     */
+    void render(build_env_ref, const library_root& owning_library) const;
+};
+
+}  // namespace dds

src/dds/error/errors.hpp

@@ -43,6 +43,8 @@ enum class errc {
 
     invalid_lib_filesystem,
     invalid_pkg_filesystem,
+
+    template_error,
 };
 
 std::string      error_reference_of(errc) noexcept;

src/dds/source/file.cpp

@@ -35,6 +35,10 @@ std::optional<source_kind> dds::infer_source_kind(path_ref p) noexcept {
     auto ext_found
         = std::lower_bound(header_exts.begin(), header_exts.end(), p.extension(), std::less<>());
     if (ext_found != header_exts.end() && *ext_found == p.extension()) {
+        auto stem = p.stem();
+        if (stem.extension() == ".config") {
+            return source_kind::header_template;
+        }
         return source_kind::header;
     }
 
@@ -44,11 +48,11 @@ std::optional<source_kind> dds::infer_source_kind(path_ref p) noexcept {
         return std::nullopt;
     }
 
-    if (ends_with(p.stem().string(), ".test")) {
+    if (p.stem().extension() == ".test") {
         return source_kind::test;
     }
 
-    if (ends_with(p.stem().string(), ".main")) {
+    if (p.stem().extension() == ".main") {
         return source_kind::app;
     }
 

src/dds/source/file.hpp

@@ -9,6 +9,7 @@ namespace dds {
 
 enum class source_kind {
     header,
+    header_template,
     source,
     test,
     app,
@@ -17,11 +18,22 @@ enum class source_kind {
 std::optional<source_kind> infer_source_kind(path_ref) noexcept;
 
 struct source_file {
-    fs::path    path;
-    fs::path    basis_path;
+    /**
+     * The actual path to the file
+     */
+    fs::path path;
+    /**
+     * The path to source root that contains the file in question
+     */
+    fs::path basis_path;
+    /**
+     * The kind of the source file
+     */
     source_kind kind;
 
     static std::optional<source_file> from_path(path_ref path, path_ref base_path) noexcept;
+
+    fs::path relative_path() const noexcept { return fs::relative(path, basis_path); }
 };
 
 using source_list = std::vector<source_file>;

src/dds/source/file.test.cpp

@@ -0,0 +1,16 @@
+#include <dds/source/file.hpp>
+
+#include <catch2/catch.hpp>
+
+using dds::source_kind;
+
+TEST_CASE("Infer source kind") {
+    using dds::infer_source_kind;
+    auto k = infer_source_kind("foo.h");
+    CHECK(k == source_kind::header);
+    CHECK(infer_source_kind("foo.hpp") == source_kind::header);
+    CHECK_FALSE(infer_source_kind("foo.txt"));  // Not a source file extension
+
+    CHECK(infer_source_kind("foo.hh") == source_kind::header);
+    CHECK(infer_source_kind("foo.config.hpp") == source_kind::header_template);
+}

tests/basics/config_template/copy_only/src/info.config.hpp

@@ -0,0 +1,5 @@
+#pragma once
+
+#include <string>
+
+int config_file_value = 42;

tests/basics/config_template/copy_only/src/info.test.cpp

@@ -0,0 +1,5 @@
+#include <info.hpp>
+
+#include <cassert>
+
+int main() { assert(config_file_value == 42); }

tests/basics/config_template/simple/library.jsonc

@@ -0,0 +1,3 @@
+{
+    "name": "test-library"
+}

tests/basics/config_template/simple/package.jsonc

@@ -0,0 +1,5 @@
+{
+    "name": "test-simple",
+    "version": "1.2.3-gamma",
+    "namespace": "test"
+}

tests/basics/config_template/simple/src/simple/config.config.hpp

@@ -0,0 +1,5 @@
+#pragma once
+
+#include <string_view>
+
+std::string_view lib_name = __dds(lib.name);

tests/basics/config_template/simple/src/simple/simple.test.cpp

@@ -0,0 +1,5 @@
+#include <simple/config.hpp>
+
+#include <cassert>
+
+int main() { assert(lib_name == "test-library"); }

tests/basics/config_template/test_config_template.py

@@ -0,0 +1,26 @@
+import pytest
+from time import sleep
+
+from tests import DDS, dds_fixture_conf_1
+
+
+@dds_fixture_conf_1('copy_only')
+def test_config_template(dds: DDS):
+    generated_fpath = dds.build_dir / '__dds/gen/info.hpp'
+    assert not generated_fpath.is_file()
+    dds.build()
+    assert generated_fpath.is_file()
+
+    # Check that re-running the build will not update the generated file (the
+    # file's content has not changed. Re-generating it would invalidate the
+    # cache and force a false-rebuild.)
+    start_time = generated_fpath.stat().st_mtime
+    sleep(0.1)  # Wait just long enough to register a new stamp time
+    dds.build()
+    new_time = generated_fpath.stat().st_mtime
+    assert new_time == start_time
+
+
+@dds_fixture_conf_1('simple')
+def test_simple_substitution(dds: DDS):
+    dds.build()

tests/dds.py

@@ -52,11 +52,11 @@ class DDS:
         full_cmd = itertools.chain([self.dds_exe], cmd)
         return proc.run(full_cmd, cwd=cwd or self.source_root)
 
-    def run(self, cmd: proc.CommandLine, *,
-            cwd: Path = None) -> subprocess.CompletedProcess:
+    def run(self, cmd: proc.CommandLine, *, cwd: Path = None,
+            check=True) -> subprocess.CompletedProcess:
         cmdline = list(proc.flatten_cmd(cmd))
         res = self.run_unchecked(cmd, cwd=cwd)
-        if res.returncode != 0:
+        if res.returncode != 0 and check:
             raise subprocess.CalledProcessError(
                 res.returncode, [self.dds_exe] + cmdline, res.stdout)
         return res
@@ -86,18 +86,22 @@ class DDS:
               toolchain: str = None,
               apps: bool = True,
               warnings: bool = True,
-              tests: bool = True) -> subprocess.CompletedProcess:
-        return self.run([
-            'build',
-            f'--out={self.build_dir}',
-            f'--toolchain={toolchain or self.default_builtin_toolchain}',
-            f'--catalog={self.catalog_path}',
-            f'--repo-dir={self.repo_dir}',
-            ['--no-tests'] if not tests else [],
-            ['--no-apps'] if not apps else [],
-            ['--no-warnings'] if not warnings else [],
-            self.project_dir_arg,
-        ])
+              tests: bool = True,
+              check: bool = True) -> subprocess.CompletedProcess:
+        return self.run(
+            [
+                'build',
+                f'--out={self.build_dir}',
+                f'--toolchain={toolchain or self.default_builtin_toolchain}',
+                f'--catalog={self.catalog_path}',
+                f'--repo-dir={self.repo_dir}',
+                ['--no-tests'] if not tests else [],
+                ['--no-apps'] if not apps else [],
+                ['--no-warnings'] if not warnings else [],
+                self.project_dir_arg,
+            ],
+            check=check,
+        )
 
     def sdist_create(self) -> subprocess.CompletedProcess:
         return self.run([

tools/gen-catalog-json.py

@@ -167,6 +167,17 @@ packages = [
                 'neo-concepts': '^0.2.1',
             }),
     ]),
+    Package('ctre', [
+        Version(
+            '2.7.0',
+            description=
+            'A compile-time PCRE (almost) compatible regular expression matcher',
+            remote=Git(
+                'https://github.com/hanickadot/compile-time-regular-expressions.git',
+                'v2.7',
+                auto_lib='hanickadot/ctre',
+            ))
+    ]),
     many_versions(
         'spdlog',
         (