Got some feedback from azerupi and added a DummyBook builder

tests/dummy-book/SUMMARY.md

@@ -0,0 +1,9 @@
+# Summary
+
+[Introduction](intro.md)
+
+- [First Chapter](./first/index.md)
+    - [Nested Chapter](./first/nested.md)
+- [Second Chapter](./second.md)
+
+[Conclusion](./conclusion.md)

tests/dummy-book/conclusion.md

@@ -0,0 +1 @@
+# Conclusion

tests/dummy-book/first/index.md

@@ -0,0 +1,3 @@
+# First Chapter
+
+more text.

tests/dummy-book/first/nested.md

@@ -0,0 +1,7 @@
+# Nested Chapter
+
+This file has some testable code.
+
+```rust
+assert!($TEST_STATUS);
+```

tests/dummy-book/intro.md

@@ -0,0 +1,3 @@
+# Introduction
+
+Here's some interesting text...

tests/dummy-book/second.md

@@ -0,0 +1 @@
+# Second Chapter

tests/helpers.rs

@@ -2,7 +2,8 @@
 //! the `MDBook` initialization and build/rendering process.
 //!
 //! This will create an entire book in a temporary directory using some
-//! dummy content.
+//! dummy contents from the `tests/dummy-book/` directory.
+
 
 #![allow(dead_code, unused_variables, unused_imports)]
 extern crate tempdir;
@@ -14,36 +15,12 @@ use std::io::{Read, Write};
 use tempdir::TempDir;
 
 
-const SUMMARY_MD: &'static str = "# Summary
-
-[Introduction](intro.md)
-
-- [First Chapter](./first/index.md)
-    - [Nested Chapter](./first/nested.md)
-- [Second Chapter](./second.md)
-
-[Conclusion](./conclusion.md)
-";
-
-const INTRO: &'static str = "# Introduction
-
-Here's some interesting text...";
-
-const FIRST: &'static str = "# First Chapter
-
-more text.";
-
-const NESTED: &'static str = r#"# Nested Chapter
-
-This file has some testable code.
-
-```rust
-assert!($TEST_STATUS);
-```"#;
-
-const SECOND: &'static str = "# Second Chapter";
-
-const CONCLUSION: &'static str = "# Conclusion";
+const SUMMARY_MD: &'static str = include_str!("dummy-book/SUMMARY.md");
+const INTRO: &'static str = include_str!("dummy-book/intro.md");
+const FIRST: &'static str = include_str!("dummy-book/first/index.md");
+const NESTED: &'static str = include_str!("dummy-book/first/nested.md");
+const SECOND: &'static str = include_str!("dummy-book/second.md");
+const CONCLUSION: &'static str = include_str!("dummy-book/conclusion.md");
 
 
 /// Create a dummy book in a temporary directory, using the contents of
@@ -53,47 +30,69 @@ const CONCLUSION: &'static str = "# Conclusion";
 /// `assert!($TEST_STATUS)`. If you want to check MDBook's testing
 /// functionality, `$TEST_STATUS` can be substitute for either `true` or
 /// `false`. This is done using the `passing_test` parameter.
-pub fn create_book(passing_test: bool) -> TempDir {
-    let temp = TempDir::new("dummy_book").unwrap();
-
-    let src = temp.path().join("src");
-    fs::create_dir_all(&src).unwrap();
-
-    File::create(src.join("SUMMARY.md"))
-        .unwrap()
-        .write_all(SUMMARY_MD.as_bytes())
-        .unwrap();
-    File::create(src.join("intro.md"))
-        .unwrap()
-        .write_all(INTRO.as_bytes())
-        .unwrap();
-
-    let first = src.join("first");
-    fs::create_dir_all(&first).unwrap();
-    File::create(first.join("index.md"))
-        .unwrap()
-        .write_all(FIRST.as_bytes())
-        .unwrap();
-
-    let to_substitute = if passing_test { "true" } else { "false" };
-    let nested_text = NESTED.replace("$TEST_STATUS", to_substitute);
-    File::create(first.join("nested.md"))
-        .unwrap()
-        .write_all(nested_text.as_bytes())
-        .unwrap();
-
-    File::create(src.join("second.md"))
-        .unwrap()
-        .write_all(SECOND.as_bytes())
-        .unwrap();
-    File::create(src.join("conclusion.md"))
-        .unwrap()
-        .write_all(CONCLUSION.as_bytes())
-        .unwrap();
-
-    temp
+#[derive(Clone, Debug, PartialEq)]
+pub struct DummyBook {
+    passing_test: bool,
 }
 
+impl DummyBook {
+    /// Create a new `DummyBook` with all the defaults.
+    pub fn new() -> DummyBook {
+        DummyBook::default()
+    }
+
+    /// Whether the doc-test included in the "Nested Chapter" should pass or
+    /// fail (it passes by default).
+    pub fn with_passing_test(&mut self, test_passes: bool) -> &mut Self {
+        self.passing_test = test_passes;
+        self
+    }
+
+    /// Write a book to a temporary directory using the provided settings.
+    ///
+    /// # Note
+    ///
+    /// If this fails for any reason it will `panic!()`. If we can't write to a
+    /// temporary directory then chances are you've got bigger problems...
+    pub fn build(&self) -> TempDir {
+        let temp = TempDir::new("dummy_book").unwrap();
+
+        let src = temp.path().join("src");
+        fs::create_dir_all(&src).unwrap();
+
+        let first = src.join("first");
+        fs::create_dir_all(&first).unwrap();
+
+        let to_substitute = if self.passing_test { "true" } else { "false" };
+        let nested_text = NESTED.replace("$TEST_STATUS", to_substitute);
+
+        let inputs = vec![
+            (src.join("SUMMARY.md"), SUMMARY_MD),
+            (src.join("intro.md"), INTRO),
+            (first.join("index.md"), FIRST),
+            (first.join("nested.md"), &nested_text),
+            (src.join("second.md"), SECOND),
+            (src.join("conclusion.md"), CONCLUSION),
+        ];
+
+        for (path, content) in inputs {
+            File::create(path)
+                .unwrap()
+                .write_all(content.as_bytes())
+                .unwrap();
+        }
+
+        temp
+    }
+}
+
+impl Default for DummyBook {
+    fn default() -> DummyBook {
+        DummyBook { passing_test: true }
+    }
+}
+
+
 /// Read the contents of the provided file into memory and then iterate through
 /// the list of strings asserting that the file contains all of them.
 pub fn assert_contains_strings<P: AsRef<Path>>(filename: P, strings: &[&str]) {

tests/init.rs

@@ -5,8 +5,10 @@ use tempdir::TempDir;
 use mdbook::MDBook;
 
 
+/// Run `mdbook init` in an empty directory and make sure the default files
+/// are created.
 #[test]
-fn run_mdbook_init() {
+fn base_mdbook_init_should_create_default_content() {
     let created_files = vec!["book", "src", "src/SUMMARY.md", "src/chapter_1.md"];
 
     let temp = TempDir::new("mdbook").unwrap();
@@ -22,13 +24,15 @@ fn run_mdbook_init() {
     }
 }
 
+/// Set some custom arguments for where to place the source and destination
+/// files, then call `mdbook init`.
 #[test]
-fn run_mdbook_init_with_custom_args() {
+fn run_mdbook_init_with_custom_book_and_src_locations() {
     let created_files = vec!["out", "in", "in/SUMMARY.md", "in/chapter_1.md"];
 
     let temp = TempDir::new("mdbook").unwrap();
     for file in &created_files {
-        assert!(!temp.path().join(file).exists());
+        assert!(!temp.path().join(file).exists(), "{} shouldn't exist yet!", file);
     }
 
     let mut md = MDBook::new(temp.path())
@@ -38,6 +42,6 @@ fn run_mdbook_init_with_custom_args() {
     md.init().unwrap();
 
     for file in &created_files {
-        assert!(temp.path().join(file).exists(), "{} doesn't exist", file);
+        assert!(temp.path().join(file).exists(), "{} should have been created by `mdbook init`", file);
     }
 }

tests/rendered_output.rs

@@ -5,9 +5,10 @@ mod helpers;
 use mdbook::MDBook;
 
 
+/// Make sure you can load the dummy book and build it without panicking.
 #[test]
 fn build_the_dummy_book() {
-    let temp = helpers::create_book(true);
+    let temp = helpers::DummyBook::default().build();
     let mut md = MDBook::new(temp.path());
 
     md.build().unwrap();
@@ -15,7 +16,7 @@ fn build_the_dummy_book() {
 
 #[test]
 fn by_default_mdbook_generates_rendered_content_in_the_book_directory() {
-    let temp = helpers::create_book(false);
+    let temp = helpers::DummyBook::default().build();
     let mut md = MDBook::new(temp.path());
 
     assert!(!temp.path().join("book").exists());
@@ -27,7 +28,7 @@ fn by_default_mdbook_generates_rendered_content_in_the_book_directory() {
 
 #[test]
 fn make_sure_bottom_level_files_contain_links_to_chapters() {
-    let temp = helpers::create_book(false);
+    let temp = helpers::DummyBook::default().build();
     let mut md = MDBook::new(temp.path());
     md.build().unwrap();
 
@@ -49,7 +50,7 @@ fn make_sure_bottom_level_files_contain_links_to_chapters() {
 
 #[test]
 fn check_correct_cross_links_in_nested_dir() {
-    let temp = helpers::create_book(false);
+    let temp = helpers::DummyBook::default().build();
     let mut md = MDBook::new(temp.path());
     md.build().unwrap();
 
@@ -72,7 +73,7 @@ fn check_correct_cross_links_in_nested_dir() {
 
 #[test]
 fn rendered_code_has_playpen_stuff() {
-    let temp = helpers::create_book(true);
+    let temp = helpers::DummyBook::default().build();
     let mut md = MDBook::new(temp.path());
     md.build().unwrap();
 
@@ -95,7 +96,7 @@ fn chapter_content_appears_in_rendered_document() {
         ("conclusion.html", "Conclusion"),
     ];
 
-    let temp = helpers::create_book(true);
+    let temp = helpers::DummyBook::default().build();
     let mut md = MDBook::new(temp.path());
     md.build().unwrap();
 

tests/testing.rs

@@ -7,7 +7,9 @@ use mdbook::MDBook;
 
 #[test]
 fn mdbook_can_correctly_test_a_passing_book() {
-    let temp = helpers::create_book(true);
+    let temp = helpers::DummyBook::default()
+        .with_passing_test(true)
+        .build();
     let mut md = MDBook::new(temp.path());
 
     assert!(md.test(vec![]).is_ok());
@@ -15,7 +17,9 @@ fn mdbook_can_correctly_test_a_passing_book() {
 
 #[test]
 fn mdbook_detects_book_with_failing_tests() {
-    let temp = helpers::create_book(false);
+    let temp = helpers::DummyBook::default()
+        .with_passing_test(false)
+        .build();
     let mut md: MDBook = MDBook::new(temp.path());
 
     assert!(md.test(vec![]).is_err());