Merge pull request 'Extract pure logic out of RSX components into unit-testable handlers modules' (#9) from worktree-extract-rsx-logic into main

Reviewed-on: #9

Cargo.lock

@@ -3400,9 +3400,9 @@ dependencies = [
 
 [[package]]
 name = "rustls"
-version = "0.23.43"
+version = "0.23.45"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0283386ce02abc0151e1761d08802dfe86c173b0b494af5cbc086574e453da06"
+checksum = "0d41d731c7d2f962d1ccc364cec258de3c0e93b38c2fb3ba97ac74513048d634"
 dependencies = [
  "aws-lc-rs",
  "once_cell",

crates/web/src/app/article_row/component.rs

@@ -1,3 +1,4 @@
+use super::handlers::score_percent;
 use crate::api;
 use crate::api::ArticleView;
 use crate::components::badge::{Badge, BadgeVariant};
@@ -6,7 +7,7 @@ use dioxus::prelude::*;
 
 #[component]
 pub fn ArticleRow(article: ArticleView) -> Element {
-    let score_pct = article.final_score.map(|s| (s * 100.0).round() as i32);
+    let score_pct = score_percent(article.final_score);
     rsx! {
         li { class: "article-row",
             div { class: "article-row-header",

crates/web/src/app/article_row/handlers.rs

@@ -0,0 +1,29 @@
+/// Converts a fractional relevance score into a whole-number percentage for
+/// the row's badge, rounding rather than truncating so e.g. 0.995 shows 100%
+/// instead of 99%.
+pub fn score_percent(final_score: Option<f32>) -> Option<i32> {
+    final_score.map(|s| (s * 100.0).round() as i32)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn no_score_yields_no_percent() {
+        assert_eq!(score_percent(None), None);
+    }
+
+    #[test]
+    fn score_is_rounded_not_truncated() {
+        assert_eq!(score_percent(Some(0.995)), Some(100));
+        assert_eq!(score_percent(Some(0.554)), Some(55));
+    }
+
+    #[test]
+    fn score_is_scaled_to_a_percentage() {
+        assert_eq!(score_percent(Some(0.5)), Some(50));
+        assert_eq!(score_percent(Some(0.0)), Some(0));
+        assert_eq!(score_percent(Some(1.0)), Some(100));
+    }
+}

crates/web/src/app/article_row/mod.rs

@@ -0,0 +1,4 @@
+mod component;
+mod handlers;
+
+pub use component::*;

crates/web/src/app/handlers.rs

@@ -0,0 +1,48 @@
+use crate::api::FeedView;
+
+/// Heading text for the article list: the selected feed's title, "Feed" as a
+/// placeholder while that feed's title hasn't loaded yet, or "All articles"
+/// when no feed is selected.
+pub fn feed_heading(selected_feed_id: Option<&str>, feeds: Option<&[FeedView]>) -> String {
+    match selected_feed_id {
+        None => "All articles".to_string(),
+        Some(id) => feeds
+            .and_then(|feeds| feeds.iter().find(|f| f.id == id))
+            .map(|f| f.title.clone())
+            .unwrap_or_else(|| "Feed".to_string()),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn feed(id: &str, title: &str) -> FeedView {
+        FeedView {
+            id: id.to_string(),
+            title: title.to_string(),
+            url: format!("https://example.com/{id}.xml"),
+        }
+    }
+
+    #[test]
+    fn no_selection_shows_all_articles() {
+        assert_eq!(feed_heading(None, None), "All articles");
+    }
+
+    #[test]
+    fn selected_feed_shows_its_title() {
+        let feeds = vec![feed("1", "Rust Blog"), feed("2", "Hacker News")];
+        assert_eq!(feed_heading(Some("2"), Some(&feeds)), "Hacker News");
+    }
+
+    /// The feed list may still be loading (or the id may be stale) when a
+    /// selection is made, so fall back to a placeholder rather than panic
+    /// or show a blank heading.
+    #[test]
+    fn unresolved_selection_falls_back_to_placeholder() {
+        assert_eq!(feed_heading(Some("missing"), None), "Feed");
+        let feeds = vec![feed("1", "Rust Blog")];
+        assert_eq!(feed_heading(Some("missing"), Some(&feeds)), "Feed");
+    }
+}

crates/web/src/app/mod.rs

@@ -1,4 +1,5 @@
 mod article_row;
+mod handlers;
 mod subscribe_form;
 
 use crate::api;
@@ -89,16 +90,10 @@ pub fn App() -> Element {
                         SidebarTrigger {}
                         h2 {
                             {
-                                let heading = match selected_feed.read().as_ref() {
+                                let heading = handlers::feed_heading(
-                                    None => "All articles".to_string(),
+                                    selected_feed.read().as_deref(),
-                                    Some(id) => feeds
+                                    feeds.read().as_ref().and_then(|r| r.as_ref().ok()).map(|v| v.as_slice()),
-                                        .read()
+                                );
-                                        .as_ref()
-                                        .and_then(|r| r.as_ref().ok())
-                                        .and_then(|feeds| feeds.iter().find(|f| &f.id == id))
-                                        .map(|f| f.title.clone())
-                                        .unwrap_or_else(|| "Feed".to_string()),
-                                };
                                 rsx! { "{heading}" }
                             }
                         }

crates/web/src/app/subscribe_form/component.rs

@@ -1,3 +1,4 @@
+use super::handlers::{normalize_feed_url, resolve_submit_outcome, SubmitOutcome};
 use crate::api;
 use crate::components::button::{Button, ButtonVariant};
 use crate::components::input::Input;
@@ -13,22 +14,20 @@ pub fn SubscribeForm(on_subscribed: EventHandler<()>) -> Element {
     let mut submitting = use_signal(|| false);
 
     let submit = move |_| {
-        let feed_url = url.read().clone();
+        let Some(feed_url) = normalize_feed_url(&url.read()) else {
-        if feed_url.trim().is_empty() {
             return;
-        }
+        };
         spawn(async move {
             submitting.set(true);
             status.set(None);
-            match api::feeds::subscribe_feed(feed_url).await {
+            let result = api::feeds::subscribe_feed(feed_url).await;
-                Ok(count) => {
+            match resolve_submit_outcome(result.map_err(|err| err.to_string())) {
-                    status.set(Some(Ok(format!(
+                SubmitOutcome::Success { message } => {
-                        "Subscribed — pulled in {count} article(s)."
+                    status.set(Some(Ok(message)));
-                    ))));
                     url.set(String::new());
                     on_subscribed.call(());
                 }
-                Err(err) => status.set(Some(Err(err.to_string()))),
+                SubmitOutcome::Failure { message } => status.set(Some(Err(message))),
             }
             submitting.set(false);
         });

crates/web/src/app/subscribe_form/handlers.rs

@@ -0,0 +1,77 @@
+/// Trims a feed URL entered by the user, returning `None` when it's blank
+/// so the submit handler can bail out before making a request.
+pub fn normalize_feed_url(input: &str) -> Option<String> {
+    let trimmed = input.trim();
+    if trimmed.is_empty() {
+        None
+    } else {
+        Some(trimmed.to_string())
+    }
+}
+
+/// Success message shown after a feed subscription pulls in new articles.
+fn subscribed_message(article_count: usize) -> String {
+    format!("Subscribed — pulled in {article_count} article(s).")
+}
+
+/// What the form should show, and whether the URL input should be cleared,
+/// after a subscription attempt resolves.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum SubmitOutcome {
+    /// The subscription succeeded: show `message` and clear the input.
+    Success { message: String },
+    /// The subscription failed: show `message` and leave the input as-is,
+    /// so the reader can fix it up and retry.
+    Failure { message: String },
+}
+
+/// Maps a `subscribe_feed` result to what the form should do next.
+pub fn resolve_submit_outcome(result: Result<usize, String>) -> SubmitOutcome {
+    match result {
+        Ok(count) => SubmitOutcome::Success {
+            message: subscribed_message(count),
+        },
+        Err(message) => SubmitOutcome::Failure { message },
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn blank_input_normalizes_to_none() {
+        assert_eq!(normalize_feed_url(""), None);
+        assert_eq!(normalize_feed_url("   "), None);
+    }
+
+    #[test]
+    fn surrounding_whitespace_is_trimmed() {
+        assert_eq!(
+            normalize_feed_url("  https://example.com/feed.xml  "),
+            Some("https://example.com/feed.xml".to_string())
+        );
+    }
+
+    #[test]
+    fn success_reports_the_article_count_and_clears_the_input() {
+        assert_eq!(
+            resolve_submit_outcome(Ok(3)),
+            SubmitOutcome::Success {
+                message: "Subscribed — pulled in 3 article(s).".to_string()
+            }
+        );
+    }
+
+    /// A failed attempt should surface the error but leave the input alone
+    /// so the reader doesn't have to retype the URL to fix it.
+    #[test]
+    fn failure_surfaces_the_error_message() {
+        assert_eq!(
+            resolve_submit_outcome(Err("feed unreachable".to_string())),
+            SubmitOutcome::Failure {
+                message: "feed unreachable".to_string()
+            }
+        );
+    }
+}

crates/web/src/app/subscribe_form/mod.rs

@@ -0,0 +1,4 @@
+mod component;
+mod handlers;
+
+pub use component::*;