alef 0.67.0

Opinionated polyglot binding generator for Rust libraries
Documentation
use minijinja::Environment;

static TEMPLATES: &[(&str, &str)] = &[
    (
        "package_declaration.jinja",
        include_str!("templates/package_declaration.jinja"),
    ),
    (
        "object_declaration.jinja",
        include_str!("templates/object_declaration.jinja"),
    ),
    (
        "expect_object_declaration.jinja",
        include_str!("templates/expect_object_declaration.jinja"),
    ),
    (
        "actual_object_declaration.jinja",
        include_str!("templates/actual_object_declaration.jinja"),
    ),
    ("empty_class.jinja", include_str!("templates/empty_class.jinja")),
    (
        "data_class_header.jinja",
        include_str!("templates/data_class_header.jinja"),
    ),
    ("class_field.jinja", include_str!("templates/class_field.jinja")),
    (
        "enum_class_header.jinja",
        include_str!("templates/enum_class_header.jinja"),
    ),
    ("enum_variant.jinja", include_str!("templates/enum_variant.jinja")),
    (
        "sealed_class_header.jinja",
        include_str!("templates/sealed_class_header.jinja"),
    ),
    (
        "sealed_object_variant.jinja",
        include_str!("templates/sealed_object_variant.jinja"),
    ),
    (
        "variant_data_class_header.jinja",
        include_str!("templates/variant_data_class_header.jinja"),
    ),
    (
        "variant_class_field.jinja",
        include_str!("templates/variant_class_field.jinja"),
    ),
    ("variant_close.jinja", include_str!("templates/variant_close.jinja")),
    (
        "error_sealed_class_header.jinja",
        include_str!("templates/error_sealed_class_header.jinja"),
    ),
    (
        "error_object_variant.jinja",
        include_str!("templates/error_object_variant.jinja"),
    ),
    ("error_field.jinja", include_str!("templates/error_field.jinja")),
    (
        "error_variant_close.jinja",
        include_str!("templates/error_variant_close.jinja"),
    ),
    ("typealias_trait.jinja", include_str!("templates/typealias_trait.jinja")),
    ("typealias_type.jinja", include_str!("templates/typealias_type.jinja")),
    ("typealias_error.jinja", include_str!("templates/typealias_error.jinja")),
    (
        "function_signature.jinja",
        include_str!("templates/function_signature.jinja"),
    ),
    (
        "expect_function_signature.jinja",
        include_str!("templates/expect_function_signature.jinja"),
    ),
    ("doc_comment.jinja", include_str!("templates/doc_comment.jinja")),
    ("line_comment.jinja", include_str!("templates/line_comment.jinja")),
    (
        "bridge_call_with_dispatch.jinja",
        include_str!("templates/bridge_call_with_dispatch.jinja"),
    ),
    (
        "bridge_call_unit.jinja",
        include_str!("templates/bridge_call_unit.jinja"),
    ),
    (
        "bridge_call_return.jinja",
        include_str!("templates/bridge_call_return.jinja"),
    ),
    (
        "native_function_header.jinja",
        include_str!("templates/native_function_header.jinja"),
    ),
    (
        "native_result_assign.jinja",
        include_str!("templates/native_result_assign.jinja"),
    ),
    (
        "native_error_code_check.jinja",
        include_str!("templates/native_error_code_check.jinja"),
    ),
    (
        "native_error_message.jinja",
        include_str!("templates/native_error_message.jinja"),
    ),
    (
        "native_call_only.jinja",
        include_str!("templates/native_call_only.jinja"),
    ),
    (
        "native_return_expr.jinja",
        include_str!("templates/native_return_expr.jinja"),
    ),
    (
        "native_param_cstr_conversion.jinja",
        include_str!("templates/native_param_cstr_conversion.jinja"),
    ),
    (
        "native_param_bytes_conversion.jinja",
        include_str!("templates/native_param_bytes_conversion.jinja"),
    ),
    (
        "registration_variant.kt.jinja",
        include_str!("templates/registration_variant.kt.jinja"),
    ),
    (
        "jni_bridge_object_header.jinja",
        include_str!("templates/jni_bridge_object_header.jinja"),
    ),
    (
        "jni_external_fun.jinja",
        include_str!("templates/jni_external_fun.jinja"),
    ),
    ("jni_bridge_file.jinja", include_str!("templates/jni_bridge_file.jinja")),
    (
        "jni_client_class_header.jinja",
        include_str!("templates/jni_client_class_header.jinja"),
    ),
    (
        "jni_client_method_header.jinja",
        include_str!("templates/jni_client_method_header.jinja"),
    ),
    (
        "jni_streaming_client_method.jinja",
        include_str!("templates/jni_streaming_client_method.jinja"),
    ),
    (
        "kotlin_client_method.jinja",
        include_str!("templates/kotlin_client_method.jinja"),
    ),
    (
        "service_class_header.jinja",
        include_str!("templates/service_class_header.jinja"),
    ),
    (
        "service_registration_method.jinja",
        include_str!("templates/service_registration_method.jinja"),
    ),
    (
        "service_run_method.jinja",
        include_str!("templates/service_run_method.jinja"),
    ),
    (
        "service_finalize_method.jinja",
        include_str!("templates/service_finalize_method.jinja"),
    ),
    (
        "kotlin_streaming_client_method.jinja",
        include_str!("templates/kotlin_streaming_client_method.jinja"),
    ),
    (
        "client_class_header.jinja",
        include_str!("templates/client_class_header.jinja"),
    ),
    (
        "client_close_method.jinja",
        include_str!("templates/client_close_method.jinja"),
    ),
    (
        "jni_streaming_extern_comment.jinja",
        include_str!("templates/jni_streaming_extern_comment.jinja"),
    ),
    (
        "jni_client_close_method.jinja",
        include_str!("templates/jni_client_close_method.jinja"),
    ),
    ("jni_client_file.jinja", include_str!("templates/jni_client_file.jinja")),
    ("jni_unit_body.jinja", include_str!("templates/jni_unit_body.jinja")),
    (
        "jni_deserialize_body.jinja",
        include_str!("templates/jni_deserialize_body.jinja"),
    ),
    (
        "jni_passthrough_body.jinja",
        include_str!("templates/jni_passthrough_body.jinja"),
    ),
    (
        "jni_capsule_body.jinja",
        include_str!("templates/jni_capsule_body.jinja"),
    ),
    ("jni_opaque_body.jinja", include_str!("templates/jni_opaque_body.jinja")),
    (
        "jni_opaque_optional_body.jinja",
        include_str!("templates/jni_opaque_optional_body.jinja"),
    ),
    (
        "jni_client_constructor.jinja",
        include_str!("templates/jni_client_constructor.jinja"),
    ),
    (
        "data_class_inline.jinja",
        include_str!("templates/data_class_inline.jinja"),
    ),
    (
        "data_class_header_only.jinja",
        include_str!("templates/data_class_header_only.jinja"),
    ),
    (
        "data_class_field_line.jinja",
        include_str!("templates/data_class_field_line.jinja"),
    ),
    (
        "data_class_close.jinja",
        include_str!("templates/data_class_close.jinja"),
    ),
    (
        "value_method_mapper.jinja",
        include_str!("templates/value_method_mapper.jinja"),
    ),
    (
        "json_property_annotation.jinja",
        include_str!("templates/json_property_annotation.jinja"),
    ),
    (
        "enum_json_property_variant_inline.jinja",
        include_str!("templates/enum_json_property_variant_inline.jinja"),
    ),
    (
        "enum_json_property_variant_multiline.jinja",
        include_str!("templates/enum_json_property_variant_multiline.jinja"),
    ),
    ("enum_wire_arm.jinja", include_str!("templates/enum_wire_arm.jinja")),
    (
        "enum_wire_multivalue_arm.jinja",
        include_str!("templates/enum_wire_multivalue_arm.jinja"),
    ),
    (
        "sealed_variant_inline.jinja",
        include_str!("templates/sealed_variant_inline.jinja"),
    ),
    (
        "sealed_variant_header.jinja",
        include_str!("templates/sealed_variant_header.jinja"),
    ),
    (
        "sealed_variant_field.jinja",
        include_str!("templates/sealed_variant_field.jinja"),
    ),
    (
        "sealed_variant_close.jinja",
        include_str!("templates/sealed_variant_close.jinja"),
    ),
    (
        "sealed_vec_serializer_block.jinja",
        include_str!("templates/sealed_vec_serializer_block.jinja"),
    ),
    (
        "error_variant_inline.jinja",
        include_str!("templates/error_variant_inline.jinja"),
    ),
    (
        "error_variant_header.jinja",
        include_str!("templates/error_variant_header.jinja"),
    ),
    (
        "error_variant_field.jinja",
        include_str!("templates/error_variant_field.jinja"),
    ),
    (
        "error_variant_close_multiline.jinja",
        include_str!("templates/error_variant_close_multiline.jinja"),
    ),
    (
        "error_open_property.jinja",
        include_str!("templates/error_open_property.jinja"),
    ),
    (
        "async_bridge_client_return.jinja",
        include_str!("templates/async_bridge_client_return.jinja"),
    ),
    (
        "async_bridge_return.jinja",
        include_str!("templates/async_bridge_return.jinja"),
    ),
    (
        "bridge_client_return.jinja",
        include_str!("templates/bridge_client_return.jinja"),
    ),
    ("bridge_return.jinja", include_str!("templates/bridge_return.jinja")),
];

pub(crate) fn make_env() -> Environment<'static> {
    let mut env = Environment::new();
    env.set_trim_blocks(true);
    env.set_lstrip_blocks(true);
    env.set_keep_trailing_newline(true);
    for (name, src) in TEMPLATES {
        env.add_template(name, src).expect("built-in template is valid");
    }
    env
}

pub(crate) fn render(template_name: &str, ctx: minijinja::Value) -> String {
    let rendered = make_env()
        .get_template(template_name)
        .unwrap_or_else(|_| panic!("template {template_name} not found"))
        .render(ctx)
        .unwrap_or_else(|e| panic!("template {template_name} failed to render: {e}"));
    crate::core::keep_marker::strip_keep_markers(&rendered)
}

#[cfg(test)]
mod template_registration_tests {
    use super::TEMPLATES;
    use std::collections::HashSet;
    use std::path::Path;

    /// `render()` resolves names against `TEMPLATES`, not the filesystem, so a
    /// `.jinja` file added to `templates/` but never wired into this array compiles fine
    /// (`include_str!` only runs for entries that are listed) and panics only once an
    /// emitter reaches it at generation time. Compare by content rather than by
    /// registered key: some backends register a file under a shortened or aliased name,
    /// which is fine, but every file's bytes must appear in `TEMPLATES` somewhere. ~keep
    #[test]
    fn every_template_file_is_registered() {
        let templates_dir = Path::new(concat!(env!("CARGO_MANIFEST_DIR"), "/src/backends/kotlin/templates"));
        let registered_contents: HashSet<&str> = TEMPLATES.iter().map(|(_, content)| *content).collect();

        let mut unregistered = Vec::new();
        collect_unregistered(templates_dir, templates_dir, &registered_contents, &mut unregistered);
        unregistered.sort();
        assert!(
            unregistered.is_empty(),
            "found .jinja file(s) in templates/ whose content is not registered in TEMPLATES: {unregistered:?}"
        );
    }

    fn collect_unregistered(
        root: &Path,
        dir: &Path,
        registered_contents: &HashSet<&str>,
        unregistered: &mut Vec<String>,
    ) {
        for entry in std::fs::read_dir(dir).expect("read templates directory") {
            let entry = entry.expect("read templates directory entry");
            let path = entry.path();
            if path.is_dir() {
                collect_unregistered(root, &path, registered_contents, unregistered);
                continue;
            }
            if path.extension().and_then(|ext| ext.to_str()) != Some("jinja") {
                continue;
            }
            let content = std::fs::read_to_string(&path).expect("read template file");
            if !registered_contents.contains(content.as_str()) {
                let relative = path
                    .strip_prefix(root)
                    .expect("template path under templates root")
                    .to_str()
                    .expect("template path is valid UTF-8")
                    .replace('\\', "/");
                unregistered.push(relative);
            }
        }
    }
}