Various changes

Pin to a specific toolchain version
Format checking functionality
Add a test to check the code formatting.
Remove macro_use attribute

crates/tools/src/lib.rs

@@ -4,9 +4,11 @@ extern crate teraron;
 
 use std::{
     path::{Path, PathBuf},
+    process::Command,
 };
 
 use itertools::Itertools;
+use failure::bail;
 
 pub use teraron::{Mode, Verify, Overwrite};
 
@@ -15,6 +17,7 @@ pub type Result<T> = ::std::result::Result<T, failure::Error>;
 pub const GRAMMAR: &str = "crates/ra_syntax/src/grammar.ron";
 pub const SYNTAX_KINDS: &str = "crates/ra_syntax/src/syntax_kinds/generated.rs.tera";
 pub const AST: &str = "crates/ra_syntax/src/ast/generated.rs.tera";
+const TOOLCHAIN: &str = "beta-2018-10-30";
 
 #[derive(Debug)]
 pub struct Test {
@@ -80,3 +83,29 @@ pub fn project_root() -> PathBuf {
         .unwrap()
         .to_path_buf()
 }
+
+pub fn run(cmdline: &str, dir: &str) -> Result<()> {
+    eprintln!("\nwill run: {}", cmdline);
+    let project_dir = project_root().join(dir);
+    let mut args = cmdline.split_whitespace();
+    let exec = args.next().unwrap();
+    let status = Command::new(exec)
+        .args(args)
+        .current_dir(project_dir)
+        .status()?;
+    if !status.success() {
+        bail!("`{}` exited with {}", cmdline, status);
+    }
+    Ok(())
+}
+
+pub fn run_rustfmt(mode: Mode) -> Result<()> {
+    run(&format!("rustup install {}", TOOLCHAIN), ".")?;
+    run(&format!("rustup component add rustfmt-preview --toolchain {}", TOOLCHAIN), ".")?;
+    if mode == Verify {
+        run(&format!("rustup run {} -- cargo fmt -- --check", TOOLCHAIN), ".")?;
+    } else {
+        run(&format!("rustup run {} -- cargo fmt", TOOLCHAIN), ".")?;
+    }
+    Ok(())
+}

crates/tools/src/main.rs

@@ -1,5 +1,4 @@
 extern crate clap;
-#[macro_use]
 extern crate failure;
 extern crate tools;
 extern crate walkdir;
@@ -10,11 +9,11 @@ use std::{
     collections::HashMap,
     fs,
     path::{Path, PathBuf},
-    process::Command,
 };
 use tools::{
-    collect_tests, Result, Test, generate, Mode, Overwrite, Verify, project_root,
+    collect_tests, Result, Test, generate, Mode, Overwrite, Verify, run, run_rustfmt,
 };
+use failure::bail;
 
 const GRAMMAR_DIR: &str = "./crates/ra_syntax/src/grammar";
 const INLINE_TESTS_DIR: &str = "./crates/ra_syntax/tests/data/parser/inline";
@@ -42,7 +41,7 @@ fn main() -> Result<()> {
         ("install-code", _) => install_code_extension()?,
         ("gen-tests", _) => gen_tests(mode)?,
         ("gen-syntax", _) => generate(Overwrite)?,
-        ("format", _) => run_rustfmt()?,
+        ("format", _) => run_rustfmt(Overwrite)?,
         _ => unreachable!(),
     }
     Ok(())
@@ -145,26 +144,3 @@ fn install_code_extension() -> Result<()> {
     }
     Ok(())
 }
-
-fn run(cmdline: &'static str, dir: &str) -> Result<()> {
-    eprintln!("\nwill run: {}", cmdline);
-    let project_dir = project_root().join(dir);
-    let mut args = cmdline.split_whitespace();
-    let exec = args.next().unwrap();
-    let status = Command::new(exec)
-        .args(args)
-        .current_dir(project_dir)
-        .status()?;
-    if !status.success() {
-        bail!("`{}` exited with {}", cmdline, status);
-    }
-    Ok(())
-}
-
-fn run_rustfmt() -> Result<()> {
-    // Use beta toolchain for 2018 edition.
-    run("rustup install beta", ".")?;
-    run("rustup component add rustfmt-preview --toolchain beta", ".")?;
-    run("rustup run beta -- cargo fmt", ".")?;
-    Ok(())
-}

crates/tools/tests/cli.rs

@@ -1,7 +1,7 @@
 extern crate tools;
 
 use tools::{
-    generate, Verify
+    generate, Verify, run_rustfmt,
 };
 
 #[test]
@@ -10,3 +10,10 @@ fn verify_template_generation() {
         panic!("{}. Please update it by running `cargo gen-syntax`", error);
     }
 }
+
+#[test]
+fn check_code_formatting() {
+    if let Err(error) = run_rustfmt(Verify) {
+        panic!("{}. Please format the code by running `cargo format`", error);
+    }
+}