From 20a0b99c3d9ee66714c78b76db4d85f52803e8e4 Mon Sep 17 00:00:00 2001
From: Eric Huss <eric@huss.org>
Date: Tue, 7 Jul 2020 13:37:25 -0700
Subject: [PATCH] Fix favicon when only one is overridden.

A mistake in #1266, I neglected to also update the <link> generation
to elide the link if one of the favicon images is not included.
---
 src/renderer/html_handlebars/hbs_renderer.rs | 9 ++++++++-
 src/theme/index.hbs                          | 4 ++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/renderer/html_handlebars/hbs_renderer.rs b/src/renderer/html_handlebars/hbs_renderer.rs
index fa576998..7880817b 100644
--- a/src/renderer/html_handlebars/hbs_renderer.rs
+++ b/src/renderer/html_handlebars/hbs_renderer.rs
@@ -478,7 +478,7 @@ impl Renderer for HtmlHandlebars {
         debug!("Register handlebars helpers");
         self.register_hbs_helpers(&mut handlebars, &html_config);
 
-        let mut data = make_data(&ctx.root, &book, &ctx.config, &html_config)?;
+        let mut data = make_data(&ctx.root, &book, &ctx.config, &html_config, &theme)?;
 
         // Print version
         let mut print_content = String::new();
@@ -551,6 +551,7 @@ fn make_data(
     book: &Book,
     config: &Config,
     html_config: &HtmlConfig,
+    theme: &Theme,
 ) -> Result<serde_json::Map<String, serde_json::Value>> {
     trace!("make_data");
 
@@ -567,6 +568,12 @@ fn make_data(
         "description".to_owned(),
         json!(config.book.description.clone().unwrap_or_default()),
     );
+    if theme.favicon_png.is_some() {
+        data.insert("favicon_png".to_owned(), json!("favicon.png"));
+    }
+    if theme.favicon_svg.is_some() {
+        data.insert("favicon_svg".to_owned(), json!("favicon.svg"));
+    }
     if let Some(ref livereload) = html_config.livereload_url {
         data.insert("livereload".to_owned(), json!(livereload));
     }
diff --git a/src/theme/index.hbs b/src/theme/index.hbs
index f9d3c5aa..7ad4cbf7 100644
--- a/src/theme/index.hbs
+++ b/src/theme/index.hbs
@@ -20,8 +20,12 @@
         <meta name="viewport" content="width=device-width, initial-scale=1">
         <meta name="theme-color" content="#ffffff" />
 
+        {{#if favicon_svg}}
         <link rel="icon" href="{{ path_to_root }}favicon.svg">
+        {{/if}}
+        {{#if favicon_png}}
         <link rel="shortcut icon" href="{{ path_to_root }}favicon.png">
+        {{/if}}
         <link rel="stylesheet" href="{{ path_to_root }}css/variables.css">
         <link rel="stylesheet" href="{{ path_to_root }}css/general.css">
         <link rel="stylesheet" href="{{ path_to_root }}css/chrome.css">