Change CLI dest-dir to be relative to the current directory

This changes the `--dest-dir` flag so that it is relative to the current
directory, not the book root. This has been a source of confusion for
several people.

Fixes https://github.com/rust-lang/mdBook/issues/698

crates/mdbook-core/src/config.rs

@@ -366,7 +366,7 @@ impl TextDirection {
 #[serde(default, rename_all = "kebab-case", deny_unknown_fields)]
 #[non_exhaustive]
 pub struct BuildConfig {
-    /// Where to put built artefacts relative to the book's root directory.
+    /// Where to put built artifacts relative to the book's root directory.
     pub build_dir: PathBuf,
     /// Should non-existent markdown files specified in `SUMMARY.md` be created
     /// if they don't exist?

guide/src/cli/build.md

@@ -30,7 +30,7 @@ your default web browser after building it.
 #### `--dest-dir`
 
 The `--dest-dir` (`-d`) option allows you to change the output directory for the
-book. Relative paths are interpreted relative to the book's root directory. If
+book. Relative paths are interpreted relative to the current directory. If
 not specified it will default to the value of the `build.build-dir` key in
 `book.toml`, or to `./book`.
 

guide/src/cli/clean.md

@@ -20,7 +20,7 @@ mdbook clean path/to/book
 
 The `--dest-dir` (`-d`) option allows you to override the book's output
 directory, which will be deleted by this command. Relative paths are interpreted
-relative to the book's root directory. If not specified it will default to the
+relative to the current directory. If not specified it will default to the
 value of the `build.build-dir` key in `book.toml`, or to `./book`.
 
 ```bash

guide/src/cli/serve.md

@@ -40,7 +40,7 @@ default web browser after starting the server.
 #### `--dest-dir`
 
 The `--dest-dir` (`-d`) option allows you to change the output directory for the
-book. Relative paths are interpreted relative to the book's root directory. If
+book. Relative paths are interpreted relative to the current directory. If
 not specified it will default to the value of the `build.build-dir` key in
 `book.toml`, or to `./book`.
 

guide/src/cli/watch.md

@@ -23,7 +23,7 @@ your default web browser.
 #### `--dest-dir`
 
 The `--dest-dir` (`-d`) option allows you to change the output directory for the
-book. Relative paths are interpreted relative to the book's root directory. If
+book. Relative paths are interpreted relative to the current directory. If
 not specified it will default to the value of the `build.build-dir` key in
 `book.toml`, or to `./book`.
 

src/cmd/build.rs

@@ -2,7 +2,6 @@ use super::command_prelude::*;
 use crate::{get_book_dir, open};
 use anyhow::Result;
 use mdbook_driver::MDBook;
-use std::path::PathBuf;
 
 // Create clap subcommand arguments
 pub fn make_subcommand() -> Command {
@@ -18,9 +17,7 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     let book_dir = get_book_dir(args);
     let mut book = MDBook::load(book_dir)?;
 
-    if let Some(dest_dir) = args.get_one::<PathBuf>("dest-dir") {
+    set_dest_dir(args, &mut book);
-        book.config.build.build_dir = dest_dir.into();
-    }
 
     book.build()?;
 

src/cmd/clean.rs

@@ -21,7 +21,9 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     let book = MDBook::load(book_dir)?;
 
     let dir_to_remove = match args.get_one::<PathBuf>("dest-dir") {
-        Some(dest_dir) => dest_dir.into(),
+        Some(dest_dir) => std::env::current_dir()
+            .expect("current dir should be valid")
+            .join(dest_dir),
         None => book.root.join(&book.config.build.build_dir),
     };
 

src/cmd/command_prelude.rs

@@ -1,6 +1,7 @@
 //! Helpers for building the command-line arguments for commands.
 
 pub use clap::{Arg, ArgMatches, Command, arg};
+use mdbook_driver::MDBook;
 use std::path::PathBuf;
 
 pub trait CommandExt: Sized {
@@ -15,7 +16,7 @@ pub trait CommandExt: Sized {
                 .value_parser(clap::value_parser!(PathBuf))
                 .help(
                     "Output directory for the book\n\
-                    Relative paths are interpreted relative to the book's root directory.\n\
+                    Relative paths are interpreted relative to the current directory.\n\
                     If omitted, mdBook uses build.build-dir from book.toml \
                     or defaults to `./book`.",
                 ),
@@ -57,3 +58,12 @@ impl CommandExt for Command {
         self.arg(arg)
     }
 }
+
+pub fn set_dest_dir(args: &ArgMatches, book: &mut MDBook) {
+    if let Some(dest_dir) = args.get_one::<PathBuf>("dest-dir") {
+        let build_dir = std::env::current_dir()
+            .expect("current dir should be valid")
+            .join(dest_dir);
+        book.config.build.build_dir = build_dir;
+    }
+}

src/cmd/serve.rs

@@ -62,9 +62,7 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
         book.config
             .set("output.html.live-reload-endpoint", LIVE_RELOAD_ENDPOINT)
             .expect("live-reload-endpoint update failed");
-        if let Some(dest_dir) = args.get_one::<PathBuf>("dest-dir") {
+        set_dest_dir(args, book);
-            book.config.build.build_dir = dest_dir.into();
-        }
         // Override site-url for local serving of the 404 file
         book.config.set("output.html.site-url", "/").unwrap();
     };

src/cmd/watch.rs

@@ -38,9 +38,7 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     let mut book = MDBook::load(&book_dir)?;
 
     let update_config = |book: &mut MDBook| {
-        if let Some(dest_dir) = args.get_one::<PathBuf>("dest-dir") {
+        set_dest_dir(args, book);
-            book.config.build.build_dir = dest_dir.into();
-        }
     };
     update_config(&mut book);
 

tests/testsuite/build.rs

@@ -79,9 +79,9 @@ fn dest_dir_relative_path() {
             .expect_stderr(str![[r#"
 [TIMESTAMP] [INFO] (mdbook_driver::mdbook): Book building has started
 [TIMESTAMP] [INFO] (mdbook_driver::mdbook): Running the html backend
-[TIMESTAMP] [INFO] (mdbook_html::html_handlebars::hbs_renderer): HTML book written to `[ROOT]/work/../foo`
+[TIMESTAMP] [INFO] (mdbook_html::html_handlebars::hbs_renderer): HTML book written to `[ROOT]/work/foo`
 
 "#]]);
     });
-    assert!(test.dir.join("foo/index.html").exists());
+    assert!(current_dir.join("foo/index.html").exists());
 }