Add URL hover highlighting

This changes the cursor whenever it moves to a cell which contains
part of a URL.

When a URL is hovered over, all characters that are recognized as part
of the URL will be underlined and the mouse cursor shape will be
changed. After the cursor leaves the URL, the previous hover state is
restored.

This also changes the behavior when clicking an illegal character right
in front of a URL. Previously this would still launch the URL, but strip
the illegal character. Now these clicks are ignored to make sure there's
no mismatch between underline and legal URL click positions

1 files changed, 86 insertions, 55 deletions

diff --git a/src/url.rs b/src/url.rs
index 836c36ba..a493dd37 100644
--- a/src/url.rs
+++ b/src/url.rs
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use url::Url;
+use url;
 
 // See https://tools.ietf.org/html/rfc3987#page-13
 const URL_SEPARATOR_CHARS: [char; 10] = ['<', '>', '"', ' ', '{', '}', '|', '\\', '^', '`'];
@@ -21,21 +21,35 @@ const URL_SCHEMES: [&str; 8] = [
     "http", "https", "mailto", "news", "file", "git", "ssh", "ftp",
 ];
 
-// Parser for streaming inside-out detection of URLs.
+/// URL text and origin of the original click position.
+#[derive(Debug, PartialEq)]
+pub struct Url {
+    pub text: String,
+    pub origin: usize,
+}
+
+/// Parser for streaming inside-out detection of URLs.
 pub struct UrlParser {
     state: String,
+    origin: usize,
 }
 
 impl UrlParser {
     pub fn new() -> Self {
         UrlParser {
             state: String::new(),
+            origin: 0,
         }
     }
 
     /// Advance the parser one character to the left.
     pub fn advance_left(&mut self, c: char) -> bool {
-        self.advance(c, 0)
+        if self.advance(c, 0) {
+            true
+        } else {
+            self.origin += 1;
+            false
+        }
     }
 
     /// Advance the parser one character to the right.
@@ -44,7 +58,7 @@ impl UrlParser {
     }
 
     /// Returns the URL if the parser has found any.
-    pub fn url(mut self) -> Option<String> {
+    pub fn url(mut self) -> Option<Url> {
         // Remove non-alphabetical characters before the scheme
         // https://tools.ietf.org/html/rfc3986#section-3.1
         if let Some(index) = self.state.find("://") {
@@ -57,6 +71,7 @@ impl UrlParser {
                 match c {
                     'a'...'z' | 'A'...'Z' => (),
                     _ => {
+                        self.origin = self.origin.saturating_sub(byte_index + 1);
                         self.state = self.state.split_off(byte_index + c.len_utf8());
                         break;
                     }
@@ -97,10 +112,13 @@ impl UrlParser {
         }
 
         // Check if string is valid url
-        match Url::parse(&self.state) {
+        match url::Url::parse(&self.state) {
             Ok(url) => {
-                if URL_SCHEMES.contains(&url.scheme()) {
-                    Some(self.state)
+                if URL_SCHEMES.contains(&url.scheme()) && self.origin > 0 {
+                    Some(Url {
+                        text: self.state,
+                        origin: self.origin - 1,
+                    })
                 } else {
                     None
                 }
@@ -155,12 +173,10 @@ mod tests {
         term
     }
 
-    fn url_test(input: &str, expected: &str, click_index: usize) {
+    fn url_test(input: &str, expected: &str) {
         let term = url_create_term(input);
-
-        let url = term.url_search(Point::new(0, Column(click_index)));
-
-        assert_eq!(url, Some(expected.into()));
+        let url = term.url_search(Point::new(0, Column(15)));
+        assert_eq!(url.map(|u| u.text), Some(expected.into()));
     }
 
     #[test]
@@ -168,72 +184,87 @@ mod tests {
         let term = url_create_term("no url here");
         let url = term.url_search(Point::new(0, Column(4)));
         assert_eq!(url, None);
+
+        let term = url_create_term(" https://example.org");
+        let url = term.url_search(Point::new(0, Column(0)));
+        assert_eq!(url, None);
+    }
+
+    #[test]
+    fn url_origin() {
+        let term = url_create_term(" test https://example.org ");
+        let url = term.url_search(Point::new(0, Column(10)));
+        assert_eq!(url.map(|u| u.origin), Some(4));
+
+        let term = url_create_term("https://example.org");
+        let url = term.url_search(Point::new(0, Column(0)));
+        assert_eq!(url.map(|u| u.origin), Some(0));
     }
 
     #[test]
     fn url_matching_chars() {
-        url_test("(https://example.org/test(ing))", "https://example.org/test(ing)", 5);
-        url_test("https://example.org/test(ing)", "https://example.org/test(ing)", 5);
-        url_test("((https://example.org))", "https://example.org", 5);
-        url_test(")https://example.org(", "https://example.org", 5);
-        url_test("https://example.org)", "https://example.org", 5);
-        url_test("https://example.org(", "https://example.org", 5);
-        url_test("(https://one.org/)(https://two.org/)", "https://one.org", 5);
-
-        url_test("https://[2001:db8:a0b:12f0::1]:80", "https://[2001:db8:a0b:12f0::1]:80", 5);
-        url_test("([(https://example.org/test(ing))])", "https://example.org/test(ing)", 5);
-        url_test("https://example.org/]()", "https://example.org", 5);
-        url_test("[https://example.org]", "https://example.org", 5);
-
-        url_test("'https://example.org/test'ing'''", "https://example.org/test'ing'", 5);
-        url_test("https://example.org/test'ing'", "https://example.org/test'ing'", 5);
-        url_test("'https://example.org'", "https://example.org", 5);
-        url_test("'https://example.org", "https://example.org", 5);
-        url_test("https://example.org'", "https://example.org", 5);
+        url_test("(https://example.org/test(ing))", "https://example.org/test(ing)");
+        url_test("https://example.org/test(ing)", "https://example.org/test(ing)");
+        url_test("((https://example.org))", "https://example.org");
+        url_test(")https://example.org(", "https://example.org");
+        url_test("https://example.org)", "https://example.org");
+        url_test("https://example.org(", "https://example.org");
+        url_test("(https://one.org/)(https://two.org/)", "https://one.org");
+
+        url_test("https://[2001:db8:a0b:12f0::1]:80", "https://[2001:db8:a0b:12f0::1]:80");
+        url_test("([(https://example.org/test(ing))])", "https://example.org/test(ing)");
+        url_test("https://example.org/]()", "https://example.org");
+        url_test("[https://example.org]", "https://example.org");
+
+        url_test("'https://example.org/test'ing'''", "https://example.org/test'ing'");
+        url_test("https://example.org/test'ing'", "https://example.org/test'ing'");
+        url_test("'https://example.org'", "https://example.org");
+        url_test("'https://example.org", "https://example.org");
+        url_test("https://example.org'", "https://example.org");
     }
 
     #[test]
     fn url_detect_end() {
-        url_test("https://example.org/test\u{00}ing", "https://example.org/test", 5);
-        url_test("https://example.org/test\u{1F}ing", "https://example.org/test", 5);
-        url_test("https://example.org/test\u{7F}ing", "https://example.org/test", 5);
-        url_test("https://example.org/test\u{9F}ing", "https://example.org/test", 5);
-        url_test("https://example.org/test\ting", "https://example.org/test", 5);
-        url_test("https://example.org/test ing", "https://example.org/test", 5);
+        url_test("https://example.org/test\u{00}ing", "https://example.org/test");
+        url_test("https://example.org/test\u{1F}ing", "https://example.org/test");
+        url_test("https://example.org/test\u{7F}ing", "https://example.org/test");
+        url_test("https://example.org/test\u{9F}ing", "https://example.org/test");
+        url_test("https://example.org/test\ting", "https://example.org/test");
+        url_test("https://example.org/test ing", "https://example.org/test");
     }
 
     #[test]
     fn url_remove_end_chars() {
-        url_test("https://example.org/test?ing", "https://example.org/test?ing", 5);
-        url_test("https://example.org.,;:)'!/?", "https://example.org", 5);
-        url_test("https://example.org'.", "https://example.org", 5);
+        url_test("https://example.org/test?ing", "https://example.org/test?ing");
+        url_test("https://example.org.,;:)'!/?", "https://example.org");
+        url_test("https://example.org'.", "https://example.org");
     }
 
     #[test]
     fn url_remove_start_chars() {
-        url_test("complicated:https://example.org", "https://example.org", 15);
-        url_test("test.https://example.org", "https://example.org", 10);
-        url_test(",https://example.org", "https://example.org", 5);
-        url_test("\u{2502}https://example.org", "https://example.org", 5);
+        url_test("complicated:https://example.org", "https://example.org");
+        url_test("test.https://example.org", "https://example.org");
+        url_test(",https://example.org", "https://example.org");
+        url_test("\u{2502}https://example.org", "https://example.org");
     }
 
     #[test]
     fn url_unicode() {
-        url_test("https://xn--example-2b07f.org", "https://xn--example-2b07f.org", 5);
-        url_test("https://example.org/\u{2008A}", "https://example.org/\u{2008A}", 5);
-        url_test("https://example.org/\u{f17c}", "https://example.org/\u{f17c}", 5);
-        url_test("https://üñîçøðé.com/ä", "https://üñîçøðé.com/ä", 5);
+        url_test("https://xn--example-2b07f.org", "https://xn--example-2b07f.org");
+        url_test("https://example.org/\u{2008A}", "https://example.org/\u{2008A}");
+        url_test("https://example.org/\u{f17c}", "https://example.org/\u{f17c}");
+        url_test("https://üñîçøðé.com/ä", "https://üñîçøðé.com/ä");
     }
 
     #[test]
     fn url_schemes() {
-        url_test("mailto://example.org", "mailto://example.org", 5);
-        url_test("https://example.org", "https://example.org", 5);
-        url_test("http://example.org", "http://example.org", 5);
-        url_test("news://example.org", "news://example.org", 5);
-        url_test("file://example.org", "file://example.org", 5);
-        url_test("git://example.org", "git://example.org", 5);
-        url_test("ssh://example.org", "ssh://example.org", 5);
-        url_test("ftp://example.org", "ftp://example.org", 5);
+        url_test("mailto://example.org", "mailto://example.org");
+        url_test("https://example.org", "https://example.org");
+        url_test("http://example.org", "http://example.org");
+        url_test("news://example.org", "news://example.org");
+        url_test("file://example.org", "file://example.org");
+        url_test("git://example.org", "git://example.org");
+        url_test("ssh://example.org", "ssh://example.org");
+        url_test("ftp://example.org", "ftp://example.org");
     }
 }