Add a create-missing option to book.toml.

book-example/src/format/config.md

@@ -10,6 +10,9 @@ title = "Example book"
 author = "John Doe"
 description = "The example book covers examples."
 
+[build]
+create-missing = false
+
 [output.html]
 destination = "my-example-book"
 additional-css = ["custom.css"]
@@ -45,6 +48,20 @@ src = "my-src"  # the source files will be found in `root/my-src` instead of `ro
 build-dir = "build"
 ```
 
+### Build options
+
+This controls the build process of your book.
+
+- **create-missing:** By default, any missing files specified in `SUMMARY.md`
+  will be created when the book is built. If this is `false` then the build
+  process will instead exit with an error if any files do not exist.
+
+**book.toml**
+```toml
+[build]
+create-missing = false
+```
+
 ### HTML renderer options
 The HTML renderer has a couple of options as well. All the options for the
 renderer need to be specified under the TOML table `[output.html]`.
@@ -134,4 +151,4 @@ if let Some(baz) = book_config.get_deserialized::<Vec<bool>>("output.random.baz"
 }
 
 // start the rendering process
-```
+```

src/bin/build.rs

@@ -14,7 +14,7 @@ pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
              book{n}(Defaults to ./book when omitted)'",
         )
         .arg_from_usage(
-            "--no-create 'Will not create non-existent files linked from SUMMARY.md'",
+            "--no-create 'Will not create non-existent files linked from SUMMARY.md (deprecated: use book.toml instead)'",
         )
         .arg_from_usage(
             "[dir] 'A directory for your book{n}(Defaults to Current Directory \
@@ -32,7 +32,7 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     }
 
     if args.is_present("no-create") {
-        book.create_missing = false;
+        book.create_missing = Some(false);
     }
 
     book.build()?;

src/book/mod.rs

@@ -25,8 +25,10 @@ pub struct MDBook {
     pub livereload: Option<String>,
 
     /// Should `mdbook build` create files referenced from SUMMARY.md if they
-    /// don't exist
-    pub create_missing: bool,
+    /// don't exist? If `None`, use the setting specified in `book.toml`,
+    /// otherwise use this.
+    /// This is for backward compatibility only.
+    pub create_missing: Option<bool>,
 }
 
 impl MDBook {
@@ -71,7 +73,7 @@ impl MDBook {
             renderer: Box::new(HtmlHandlebars::new()),
 
             livereload: None,
-            create_missing: true,
+            create_missing: None,
         }
     }
 
@@ -179,7 +181,9 @@ impl MDBook {
                 let path = self.get_source().join(&ch.path);
 
                 if !path.exists() {
-                    if !self.create_missing {
+                    let create_missing = self.create_missing.unwrap_or(self.config.build.create_missing);
+
+                    if !create_missing {
                         return Err(
                             format!("'{}' referenced from SUMMARY.md does not exist.", path.to_string_lossy()).into(),
                         );

src/config.rs

@@ -12,6 +12,7 @@ use errors::*;
 pub struct Config {
     /// Metadata about the book.
     pub book: BookConfig,
+    pub build: BuildConfig,
     rest: Table,
 }
 
@@ -171,8 +172,14 @@ impl<'de> Deserialize<'de> for Config {
         let book: BookConfig = table.remove("book")
                                     .and_then(|value| value.try_into().ok())
                                     .unwrap_or_default();
+
+        let build: BuildConfig = table.remove("build")
+                                      .and_then(|value| value.try_into().ok())
+                                      .unwrap_or_default();
+
         Ok(Config {
             book: book,
+            build: build,
             rest: table,
         })
     }
@@ -217,6 +224,23 @@ impl Default for BookConfig {
     }
 }
 
+/// Configuration for the build procedure.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(default, rename_all = "kebab-case")]
+pub struct BuildConfig {
+    /// Should non-existent markdown files specified in `SETTINGS.md` be created
+    /// if they don't exist?
+    pub create_missing: bool,
+}
+
+impl Default for BuildConfig {
+    fn default() -> BuildConfig {
+        BuildConfig {
+            create_missing: true,
+        }
+    }
+}
+
 #[derive(Debug, Clone, Default, PartialEq, Serialize, Deserialize)]
 #[serde(default, rename_all = "kebab-case")]
 pub struct HtmlConfig {
@@ -250,6 +274,9 @@ mod tests {
         src = "source"
         build-dir = "outputs"
 
+        [build]
+        create-missing = false
+
         [output.html]
         theme = "./themedir"
         curly-quotes = true
@@ -274,6 +301,9 @@ mod tests {
             build_dir: PathBuf::from("outputs"),
             ..Default::default()
         };
+        let build_should_be = BuildConfig {
+            create_missing: false,
+        };
         let playpen_should_be = Playpen {
             editable: true,
             editor: PathBuf::from("ace"),
@@ -290,6 +320,7 @@ mod tests {
         let got = Config::from_str(src).unwrap();
 
         assert_eq!(got.book, book_should_be);
+        assert_eq!(got.build, build_should_be);
         assert_eq!(got.html_config().unwrap(), html_should_be);
     }