From afb224b8603b0dd737a250b077c30c483affc851 Mon Sep 17 00:00:00 2001
From: Alexandre Bury <alexandre.bury@gmail.com>
Date: Thu, 11 Jan 2018 00:07:44 +0100
Subject: [PATCH] Protect against empty spans

---
 src/utils/lines/spans/chunk_iterator.rs | 14 ++++++++++
 src/utils/markup/mod.rs                 | 34 +++++++++++++++----------
 2 files changed, 35 insertions(+), 13 deletions(-)

diff --git a/src/utils/lines/spans/chunk_iterator.rs b/src/utils/lines/spans/chunk_iterator.rs
index b096334..bfd9b4d 100644
--- a/src/utils/lines/spans/chunk_iterator.rs
+++ b/src/utils/lines/spans/chunk_iterator.rs
@@ -44,6 +44,13 @@ where
     type Item = Chunk<'b>;
 
     fn next(&mut self) -> Option<Self::Item> {
+        // Protect agains empty spans
+        while self.current_span < self.spans.len()
+            && self.spans[self.current_span].text.is_empty()
+        {
+            self.current_span += 1;
+        }
+
         if self.current_span >= self.spans.len() {
             return None;
         }
@@ -111,6 +118,13 @@ where
                 // we need to look at the next span first.
                 self.current_span += 1;
 
+                // Skip empty spans
+                while self.current_span < self.spans.len()
+                    && self.spans[self.current_span].text.is_empty()
+                {
+                    self.current_span += 1;
+                }
+
                 if self.current_span >= self.spans.len() {
                     // If this was the last chunk, return as is!
                     return Some(Chunk {
diff --git a/src/utils/markup/mod.rs b/src/utils/markup/mod.rs
index f7ec329..d2aaf2c 100644
--- a/src/utils/markup/mod.rs
+++ b/src/utils/markup/mod.rs
@@ -7,7 +7,6 @@ pub mod markdown;
 
 #[cfg(feature = "markdown")]
 pub use self::markdown::MarkdownText;
-
 use owning_ref::OwningHandle;
 use owning_ref::StringRef;
 use std::borrow::Cow;
@@ -43,7 +42,6 @@ pub trait Markup {
 /// This only wraps the text and indicates how it should be parsed;
 /// it does not parse the text itself.
 pub trait MarkupText {
-
     /// Markup format to use to parse the string.
     type M: Markup;
 
@@ -67,12 +65,16 @@ impl Markup for Plain {
     type Error = ();
 
     fn parse<'a>(input: &'a str) -> Result<Vec<Span<'a>>, Self::Error> {
-        Ok(vec![
-            Span {
-                text: Cow::Borrowed(input),
-                style: Style::none(),
-            },
-        ])
+        Ok(if input.is_empty() {
+            Vec::new()
+        } else {
+            vec![
+                Span {
+                    text: Cow::Borrowed(input),
+                    style: Style::none(),
+                },
+            ]
+        })
     }
 }
 
@@ -109,8 +111,9 @@ impl StyledString {
     /// Returns a plain StyledString without any style.
     ///
     /// > You got no style, Dutch. You know that.
-    pub fn plain<S>(content: S) -> Self 
-    where S: Into<String>
+    pub fn plain<S>(content: S) -> Self
+    where
+        S: Into<String>,
     {
         Self::new(content).unwrap()
     }
@@ -138,16 +141,21 @@ impl StyledString {
     }
 
     /// Sets the content of this string to plain text.
-    pub fn set_plain<S>(&mut self, content: S) where S: Into<String> {
+    pub fn set_plain<S>(&mut self, content: S)
+    where
+        S: Into<String>,
+    {
         self.set_content(content).unwrap();
     }
 
     /// Append `content` to the end.
     ///
     /// Re-parse everything after.
-    pub fn append_content<T>(&mut self, content: T) -> Result<(), <T::M as Markup>::Error>
+    pub fn append_content<T>(
+        &mut self, content: T
+    ) -> Result<(), <T::M as Markup>::Error>
     where
-        T: MarkupText
+        T: MarkupText,
     {
         self.with_content::<T::M, _, _>(|c| c.push_str(&content.to_string()))
     }