From 7ba8274c675bbb31ac7a2618e227b380561fc5ae Mon Sep 17 00:00:00 2001
From: Gabe Berke-Williams <gabebw@gabebw.com>
Date: Sat, 31 Aug 2019 20:28:15 -0700
Subject: [PATCH] Allow multiple selectors with their own operations

---
 README.md   | 19 +++++++++++--------
 src/main.rs | 53 +++++++++++++++++++++++++++++++++++++++++------------
 2 files changed, 52 insertions(+), 20 deletions(-)

diff --git a/README.md b/README.md
index de775da..19dca67 100644
--- a/README.md
+++ b/README.md
@@ -37,23 +37,26 @@ To get an attribute, use `attr{ATTRIBUTE_NAME}`.
 
 Now let's parse a real webpage:
 
-    curl https://daringfireball.net | candle 'dl.linkedlist dt a:not([title]) {text}'
+    curl https://daringfireball.net | candle 'dl a:not([title]) {text}'
 
     Jack Dorsey’s Twitter Account Was Compromised
     NetNewsWire 5.0
-    Filmmaker Mode (a.k.a. Death to Motion Smoothing)
-    Apple Expands Third-Party Repair Program
-    Apple Sends Invitations for September 10 Event
 
 We can show the `href` attribute instead:
 
-    curl https://daringfireball.net | candle 'dl.linkedlist dt a:not([title]) attr{href}'
+    curl https://daringfireball.net | candle 'dl a:not([title]) attr{href}'
 
     https://techcrunch.com/2019/08/30/someone-hacked-jack-dorseys-own-twitter-account/
     https://inessential.com/2019/08/26/netnewswire_5_0_now_available
-    https://www.experienceuhd.com/filmmakermode
-    https://www.apple.com/newsroom/2019/08/apple-offers-customers-even-more-options-for-safe-reliable-repairs/
-    https://www.loopinsight.com/2019/08/29/apple-sends-invite-for-september-10-event/
+
+Or we can show both the text and the `href`:
+
+    curl https://daringfireball.net | candle 'dl a:not([title]) attr{href}, dl a:not([title]) {text}'
+
+    https://techcrunch.com/2019/08/30/someone-hacked-jack-dorseys-own-twitter-account/
+    https://inessential.com/2019/08/26/netnewswire_5_0_now_available
+    Jack Dorsey’s Twitter Account Was Compromised
+    NetNewsWire 5.0
 
 ## Inspiration
 
diff --git a/src/main.rs b/src/main.rs
index 756118b..45431f4 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -11,6 +11,12 @@ struct Inputs {
     html: String,
 }
 
+struct Finder<'a> {
+    selector: &'a str,
+    attr: Option<&'a str>,
+    is_text: bool,
+}
+
 fn read_from_stdin() -> Option<String> {
     // It might not be valid UTF-8, so read to a vector of bytes and convert it to UTF-8, lossily
     let mut buffer: Vec<u8> = Vec::new();
@@ -64,30 +70,40 @@ fn main() {
     }
 }
 
-fn select(document: scraper::Html, captures: regex::Captures) -> Result<Vec<String>, String> {
-    let selector = Selector::parse(captures.name("selector").unwrap().as_str())
+fn select_all(document: scraper::Html, finders: Vec<Finder>) -> Result<Vec<String>, String> {
+    let mut results: Vec<String> = Vec::new();
+    for finder in finders {
+        results.extend(select(&document, &finder)?);
+    }
+    Ok(results)
+}
+
+fn select(document: &scraper::Html, finder: &Finder) -> Result<Vec<String>, String> {
+    let selector = Selector::parse(finder.selector)
         .map_err(|e| format!("Bad CSS selector: {:?}", e.kind))?;
     let selected = document.select(&selector);
 
-    if captures.name("text").is_some() {
+    if finder.is_text {
         Ok(selected.map(|element| element.text().collect()).collect())
-    } else if let Some(attr) = captures.name("attr") {
+    } else if let Some(attr) = finder.attr {
         Ok(selected
-            .filter_map(|element| element.value().attr(attr.as_str()).map(|s| s.to_string()))
+            .filter_map(|element| element.value().attr(attr).map(|s| s.to_string()))
             .collect())
     } else {
-        Err("Unknown request".to_string())
+        Err("Unknown finder (not `{text}` or `attr{...}`".to_string())
     }
 }
 
 fn parse(inputs: Inputs) -> Result<Vec<String>, String> {
     let document = Html::parse_document(&inputs.html);
-    let re = Regex::new(r"(?P<selector>.+) (?:(?P<text>\{text\})|(attr\{(?P<attr>[^}]+)\}))$").unwrap();
-    match re.captures(&inputs.selector) {
-        Some(captures) => select(document, captures),
-        None => {
-            Err("Please specify {text} or attr{ATTRIBUTE}".to_string())
-        }
+    let re = Regex::new(r"(?P<selector>[^{}]+) (?:(?P<text>\{text\})|(attr\{(?P<attr>[^}]+)\}))[,]?\s*").unwrap();
+    let finders: Vec<Finder> = re.captures_iter(&inputs.selector)
+        .map(|c| Finder { selector: c.name("selector").unwrap().as_str(), is_text: c.name("text").is_some(), attr: c.name("attr").map(|a| a.as_str()) }).collect();
+
+    if finders.len() == 0 {
+        Err("Please specify {text} or attr{ATTRIBUTE}".to_string())
+    } else {
+        select_all(document, finders)
     }
 }
 
@@ -134,6 +150,19 @@ mod test {
         assert_eq!(result, Ok(vec!("foo".to_string())));
     }
 
+    #[test]
+    fn test_multiple_selectors(){
+        let html = r#"
+            <!DOCTYPE html>
+            <meta charset="utf-8">
+            <title>Hello, world!</title>
+            <h1 class="foo">Hello, <i>world!</i></h1>
+        "#;
+        let selector = "h1 attr{class}, h1 {text}";
+        let result = parse(build_inputs(html, selector));
+        assert_eq!(result, Ok(vec!("foo".to_string(), "Hello, world!".to_string())));
+    }
+
     #[test]
     fn test_no_text_or_attr_specification(){
         let html = r#"