feat: add attribute selection to nu_plugion_selector (#3519)

This allows the user to specify for example 
selector a -t href 
to downselect based on an attribute

Co-authored-by: ahkrr <alexhk@protonmail.com>

crates/nu_plugin_selector/Cargo.toml

@@ -10,7 +10,7 @@ version = "0.31.1"
 doctest = false
 
 [dependencies]
-nipper = "0.1.8"
+nipper = "0.1.9"
 nu-errors = { version = "0.31.1", path = "../nu-errors" }
 nu-plugin = { version = "0.31.1", path = "../nu-plugin" }
 nu-protocol = { version = "0.31.1", path = "../nu-protocol" }

crates/nu_plugin_selector/src/nu/mod.rs

@@ -3,7 +3,6 @@ use nu_plugin::Plugin;
 use nu_protocol::{
     CallInfo, Primitive, ReturnSuccess, ReturnValue, Signature, SyntaxShape, UntaggedValue, Value,
 };
-use nu_source::TaggedItem;
 
 use crate::{selector::begin_selector_query, Selector};
 
@@ -13,6 +12,12 @@ impl Plugin for Selector {
             .desc("execute selector query on html/web")
             .required("query", SyntaxShape::String, "selector query")
             .switch("as_html", "return the query output as html", Some('a'))
+            .named(
+                "attribute",
+                SyntaxShape::String,
+                "downselect based on the given attribute",
+                Some('t'),
+            )
             .filter())
     }
 
@@ -29,6 +34,9 @@ impl Plugin for Selector {
         self.query = query.as_string()?;
         self.tag = tag;
         self.as_html = call_info.args.has("as_html");
+        if call_info.args.has("attribute") {
+            self.attribute = call_info.args.expect_get("attribute")?.convert_to_string();
+        }
 
         Ok(vec![])
     }
@@ -38,12 +46,10 @@ impl Plugin for Selector {
             Value {
                 value: UntaggedValue::Primitive(Primitive::String(s)),
                 ..
-            } => Ok(
-                begin_selector_query(s, (*self.query).tagged(&self.tag), self.as_html)
-                    .into_iter()
-                    .map(ReturnSuccess::value)
-                    .collect(),
-            ),
+            } => Ok(begin_selector_query(s, &self)
+                .into_iter()
+                .map(ReturnSuccess::value)
+                .collect()),
             Value { tag, .. } => Err(ShellError::labeled_error_with_secondary(
                 "Expected text from pipeline",
                 "requires text input",

crates/nu_plugin_selector/src/selector.rs

@@ -1,11 +1,12 @@
 use nipper::Document;
 use nu_protocol::{value::StringExt, Value};
-use nu_source::{Tag, Tagged};
+use nu_source::Tag;
 
 pub struct Selector {
     pub query: String,
     pub tag: Tag,
     pub as_html: bool,
+    pub attribute: String,
 }
 
 impl Selector {
@@ -14,6 +15,7 @@ impl Selector {
             query: String::new(),
             tag: Tag::unknown(),
             as_html: false,
+            attribute: String::new(),
         }
     }
 }
@@ -24,42 +26,54 @@ impl Default for Selector {
     }
 }
 
-pub fn begin_selector_query(input: String, query: Tagged<&str>, as_html: bool) -> Vec<Value> {
-    execute_selector_query(input, query.item.to_string(), query.tag(), as_html)
+pub fn begin_selector_query(input_html: String, selector: &Selector) -> Vec<Value> {
+    match selector.attribute.is_empty() {
+        true => execute_selector_query(
+            input_html.as_str(),
+            selector.query.as_str(),
+            selector.as_html,
+        ),
+        false => execute_selector_query_with_attribute(
+            input_html.as_str(),
+            selector.query.as_str(),
+            selector.attribute.as_str(),
+        ),
+    }
 }
 
-fn execute_selector_query(
-    input_string: String,
-    query_string: String,
-    tag: impl Into<Tag>,
-    as_html: bool,
+fn execute_selector_query_with_attribute(
+    input_string: &str,
+    query_string: &str,
+    attribute: &str,
 ) -> Vec<Value> {
-    let _tag = tag.into();
-    let mut ret = vec![];
-    let doc = Document::from(&input_string);
+    let doc = Document::from(input_string);
 
-    // How to internally iterate
-    // doc.nip("tr.athing").iter().for_each(|athing| {
-    //     let title = format!("{}", athing.select(".title a").text().to_string());
-    //     let href = athing
-    //         .select(".storylink")
-    //         .attr("href")
-    //         .unwrap()
-    //         .to_string();
-    //     let title_url = format!("{} - {}\n", title, href);
-    //     ret.push(title_url.to_string_value_create_tag());
-    // });
+    doc.select(&query_string)
+        .iter()
+        .map(|selection| {
+            selection
+                .attr_or(attribute, "")
+                .to_string()
+                .to_string_value_create_tag()
+        })
+        .collect()
+}
 
-    if as_html {
-        doc.nip(&query_string).iter().for_each(|athing| {
-            ret.push(athing.html().to_string().to_string_value_create_tag());
-        });
-    } else {
-        doc.nip(&query_string).iter().for_each(|athing| {
-            ret.push(athing.text().to_string().to_string_value_create_tag());
-        });
+fn execute_selector_query(input_string: &str, query_string: &str, as_html: bool) -> Vec<Value> {
+    let doc = Document::from(input_string);
+
+    match as_html {
+        true => doc
+            .select(&query_string)
+            .iter()
+            .map(|selection| selection.html().to_string().to_string_value_create_tag())
+            .collect(),
+        false => doc
+            .select(&query_string)
+            .iter()
+            .map(|selection| selection.text().to_string().to_string_value_create_tag())
+            .collect(),
     }
-    ret
 }
 
 #[cfg(test)]