microsoft-webui-handler 3.0.2

// Copyright (c) Microsoft Corporation.
// Licensed under the MIT license.

//! Shared FAST handler support and deprecated compatibility aliases.
//!
//! FAST hydration implementations live in `fast_v2` and `fast_v3`. This module
//! owns behavior shared by both versions and keeps the original `plugin::fast`
//! public path available.

use crate::{ResponseWriter, Result};
use serde_json::Value;
use std::borrow::Cow;
use webui_protocol::attrs::camel_to_kebab;

pub use super::fast_v2::FastV2HydrationPlugin;

/// Deprecated compatibility alias for the legacy `fast` handler plugin.
///
/// Use [`FastV2HydrationPlugin`] for explicit FAST 2 compatibility. FAST 3
/// marker output lives in [`super::fast_v3::FastV3HydrationPlugin`].
#[deprecated(
    since = "0.0.11",
    note = "use plugin::fast_v2::FastV2HydrationPlugin for FAST 2 compatibility or plugin::fast_v3::FastV3HydrationPlugin for FAST 3"
)]
pub type FastHydrationPlugin = super::fast_v2::FastV2HydrationPlugin;

pub(crate) fn write_route_component_state(
    state: &Value,
    writer: &mut dyn ResponseWriter,
) -> Result<()> {
    let map = match state.as_object() {
        Some(map) => map,
        None => return Ok(()),
    };

    for (key, value) in map {
        let value = match value {
            Value::String(value) => Cow::Borrowed(value.as_str()),
            Value::Number(value) => Cow::Owned(value.to_string()),
            Value::Bool(true) => Cow::Borrowed("true"),
            Value::Bool(false) => Cow::Borrowed("false"),
            _ => continue,
        };

        let attr_name = camel_to_kebab(key);
        writer.write(" ")?;
        writer.write(&attr_name)?;
        writer.write("=\"")?;
        crate::route_renderer::write_escaped_state_attr(writer, value.as_ref())?;
        writer.write("\"")?;
    }

    Ok(())
}

#[cfg(test)]
mod tests {
    #![allow(clippy::disallowed_methods)]

    use super::*;
    use crate::plugin::{fast_v3::FastV3HydrationPlugin, HandlerPlugin};

    struct TestWriter {
        output: String,
    }

    impl TestWriter {
        fn new() -> Self {
            Self {
                output: String::new(),
            }
        }
    }

    impl ResponseWriter for TestWriter {
        fn write(&mut self, content: &str) -> Result<()> {
            self.output.push_str(content);
            Ok(())
        }

        fn end(&mut self) -> Result<()> {
            Ok(())
        }
    }

    #[test]
    #[allow(deprecated)]
    fn test_fast_alias_uses_v2_markers() {
        let mut plugin = FastHydrationPlugin::new();
        plugin.push_scope();
        let mut writer = TestWriter::new();
        assert!(plugin
            .on_binding_start("userName", false, &mut writer)
            .is_ok());
        assert_eq!(writer.output, "<!--fe-b$$start$$0$$userName$$fe-b-->");
    }

    fn render_route_state(plugin: &dyn HandlerPlugin, state: &Value) -> String {
        let mut writer = TestWriter::new();
        plugin
            .write_route_component_state(state, &mut writer)
            .unwrap();
        writer.output
    }

    #[test]
    fn fast_route_component_state_emits_scalar_attrs_only() {
        let state = serde_json::json!({
            "title": "A&B\"<>",
            "count": 42,
            "enabled": true,
            "items": [{"name": "ignored"}],
            "meta": {"nested": "ignored"},
        });
        let fast_v2 = FastV2HydrationPlugin::new();
        let fast_v3 = FastV3HydrationPlugin::new();

        for plugin in [
            &fast_v2 as &dyn HandlerPlugin,
            &fast_v3 as &dyn HandlerPlugin,
        ] {
            let output = render_route_state(plugin, &state);
            assert!(
                output.contains(r#" title="A&amp;B&quot;&lt;&gt;""#),
                "escaped scalar string attr missing: {output}"
            );
            assert!(
                output.contains(r#" count="42""#),
                "numeric scalar attr missing: {output}"
            );
            assert!(
                output.contains(r#" enabled="true""#),
                "boolean scalar attr missing: {output}"
            );
            assert!(
                !output.contains("items="),
                "complex array attr must be omitted: {output}"
            );
            assert!(
                !output.contains("meta="),
                "complex object attr must be omitted: {output}"
            );
        }
    }

    #[test]
    fn fast_route_component_state_ignores_non_object_values() {
        let state = serde_json::json!(["not", "an", "object"]);
        let fast_v2 = FastV2HydrationPlugin::new();
        let fast_v3 = FastV3HydrationPlugin::new();

        for plugin in [
            &fast_v2 as &dyn HandlerPlugin,
            &fast_v3 as &dyn HandlerPlugin,
        ] {
            assert_eq!(render_route_state(plugin, &state), "");
        }
    }
}