Auto merge of #7361 - xFrednet:5394-expand-setup-command, r=flip1995

Added `cargo dev setup git-hook` and updated `cargo dev setup intellij` including a `remove` command

This PR enables our dev tool to install a git hook that formats the code before each commit and also runs `update_lints` to make sure that everything is registered correctly. The script is located at `util/etc/pre-commit.sh`. I found it reasonable to locate it in the `util` folder and decided to add a `etc` in correlation to the main rust repo and to bring a bit of structure into it.

* The hook can be installed via: `cargo dev setup git-hook`
* And removed via: `cargo dev remove git-hook`

cc: #5394

The refactoring of `src/ide_setup.rs` to `src/setup/intellij.rs` is an extra commit to simplify the review.

---

Changes:
* Added `cargo dev setup git-hook` for formatting before every commit
* Added `cargo dev remove git-hook` to remove the hook again
* Added `cargo dev remove intellij` to remove rustc source path dependencies
* Changed `cargo dev ide_setup` to `cargo dev setup intellij`

changelog: none

This is only an internal change and therefore not worth an entry in the general change log.

---

Tested on:
* [x] Linux (by `@xFrednet)`
* [ ] Windows (All used commands run inside the git bash, so it's very likely to work as well `@xFrednet)`
* [ ] macOS

CONTRIBUTING.md

@@ -115,7 +115,7 @@ To work around this, you need to have a copy of the [rustc-repo][rustc_repo] ava
 `git clone https://github.com/rust-lang/rust/`.
 Then you can run a `cargo dev` command to automatically make Clippy use the rustc-repo via path-dependencies
 which `IntelliJ Rust` will be able to understand.
-Run `cargo dev ide_setup --repo-path <repo-path>` where `<repo-path>` is a path to the rustc repo
+Run `cargo dev setup intellij --repo-path <repo-path>` where `<repo-path>` is a path to the rustc repo
 you just cloned.
 The command will add path-dependencies pointing towards rustc-crates inside the rustc repo to
 Clippys `Cargo.toml`s and should allow `IntelliJ Rust` to understand most of the types that Clippy uses.

clippy_dev/src/fmt.rs

@@ -86,7 +86,7 @@ pub fn run(check: bool, verbose: bool) {
             },
             CliError::RaSetupActive => {
                 eprintln!(
-                    "error: a local rustc repo is enabled as path dependency via `cargo dev ide_setup`.
+                    "error: a local rustc repo is enabled as path dependency via `cargo dev setup intellij`.
 Not formatting because that would format the local repo as well!
 Please revert the changes to Cargo.tomls first."
                 );

clippy_dev/src/ide_setup.rs

@@ -1,103 +0,0 @@
-use std::fs;
-use std::fs::File;
-use std::io::prelude::*;
-use std::path::{Path, PathBuf};
-
-// This module takes an absolute path to a rustc repo and alters the dependencies to point towards
-// the respective rustc subcrates instead of using extern crate xyz.
-// This allows rust analyzer to analyze rustc internals and show proper information inside clippy
-// code. See https://github.com/rust-analyzer/rust-analyzer/issues/3517 and https://github.com/rust-lang/rust-clippy/issues/5514 for details
-
-/// # Panics
-///
-/// Panics if `rustc_path` does not lead to a rustc repo or the files could not be read
-pub fn run(rustc_path: Option<&str>) {
-    // we can unwrap here because the arg is required by clap
-    let rustc_path = PathBuf::from(rustc_path.unwrap())
-        .canonicalize()
-        .expect("failed to get the absolute repo path");
-    assert!(rustc_path.is_dir(), "path is not a directory");
-    let rustc_source_basedir = rustc_path.join("compiler");
-    assert!(
-        rustc_source_basedir.is_dir(),
-        "are you sure the path leads to a rustc repo?"
-    );
-
-    let clippy_root_manifest = fs::read_to_string("Cargo.toml").expect("failed to read ./Cargo.toml");
-    let clippy_root_lib_rs = fs::read_to_string("src/driver.rs").expect("failed to read ./src/driver.rs");
-    inject_deps_into_manifest(
-        &rustc_source_basedir,
-        "Cargo.toml",
-        &clippy_root_manifest,
-        &clippy_root_lib_rs,
-    )
-    .expect("Failed to inject deps into ./Cargo.toml");
-
-    let clippy_lints_manifest =
-        fs::read_to_string("clippy_lints/Cargo.toml").expect("failed to read ./clippy_lints/Cargo.toml");
-    let clippy_lints_lib_rs =
-        fs::read_to_string("clippy_lints/src/lib.rs").expect("failed to read ./clippy_lints/src/lib.rs");
-    inject_deps_into_manifest(
-        &rustc_source_basedir,
-        "clippy_lints/Cargo.toml",
-        &clippy_lints_manifest,
-        &clippy_lints_lib_rs,
-    )
-    .expect("Failed to inject deps into ./clippy_lints/Cargo.toml");
-}
-
-fn inject_deps_into_manifest(
-    rustc_source_dir: &Path,
-    manifest_path: &str,
-    cargo_toml: &str,
-    lib_rs: &str,
-) -> std::io::Result<()> {
-    // do not inject deps if we have aleady done so
-    if cargo_toml.contains("[target.'cfg(NOT_A_PLATFORM)'.dependencies]") {
-        eprintln!(
-            "cargo dev ide_setup: warning: deps already found inside {}, doing nothing.",
-            manifest_path
-        );
-        return Ok(());
-    }
-
-    let extern_crates = lib_rs
-        .lines()
-        // get the deps
-        .filter(|line| line.starts_with("extern crate"))
-        // we have something like "extern crate foo;", we only care about the "foo"
-        //              ↓          ↓
-        // extern crate rustc_middle;
-        .map(|s| &s[13..(s.len() - 1)]);
-
-    let new_deps = extern_crates.map(|dep| {
-        // format the dependencies that are going to be put inside the Cargo.toml
-        format!(
-            "{dep} = {{ path = \"{source_path}/{dep}\" }}\n",
-            dep = dep,
-            source_path = rustc_source_dir.display()
-        )
-    });
-
-    // format a new [dependencies]-block with the new deps we need to inject
-    let mut all_deps = String::from("[target.'cfg(NOT_A_PLATFORM)'.dependencies]\n");
-    new_deps.for_each(|dep_line| {
-        all_deps.push_str(&dep_line);
-    });
-    all_deps.push_str("\n[dependencies]\n");
-
-    // replace "[dependencies]" with
-    // [dependencies]
-    // dep1 = { path = ... }
-    // dep2 = { path = ... }
-    // etc
-    let new_manifest = cargo_toml.replacen("[dependencies]\n", &all_deps, 1);
-
-    // println!("{}", new_manifest);
-    let mut file = File::create(manifest_path)?;
-    file.write_all(new_manifest.as_bytes())?;
-
-    println!("Dependency paths injected: {}", manifest_path);
-
-    Ok(())
-}

clippy_dev/src/lib.rs

@@ -14,9 +14,9 @@ use walkdir::WalkDir;
 
 pub mod bless;
 pub mod fmt;
-pub mod ide_setup;
 pub mod new_lint;
 pub mod serve;
+pub mod setup;
 pub mod stderr_length_check;
 pub mod update_lints;
 

clippy_dev/src/main.rs

@@ -2,8 +2,8 @@
 // warn on lints, that are included in `rust-lang/rust`s bootstrap
 #![warn(rust_2018_idioms, unused_lifetimes)]
 
-use clap::{App, Arg, ArgMatches, SubCommand};
+use clap::{App, AppSettings, Arg, ArgMatches, SubCommand};
-use clippy_dev::{bless, fmt, ide_setup, new_lint, serve, stderr_length_check, update_lints};
+use clippy_dev::{bless, fmt, new_lint, serve, setup, stderr_length_check, update_lints};
 fn main() {
     let matches = get_clap_config();
 
@@ -36,7 +36,20 @@ fn main() {
         ("limit_stderr_length", _) => {
             stderr_length_check::check();
         },
-        ("ide_setup", Some(matches)) => ide_setup::run(matches.value_of("rustc-repo-path")),
+        ("setup", Some(sub_command)) => match sub_command.subcommand() {
+            ("intellij", Some(matches)) => setup::intellij::setup_rustc_src(
+                matches
+                    .value_of("rustc-repo-path")
+                    .expect("this field is mandatory and therefore always valid"),
+            ),
+            ("git-hook", Some(matches)) => setup::git_hook::install_hook(matches.is_present("force-override")),
+            _ => {},
+        },
+        ("remove", Some(sub_command)) => match sub_command.subcommand() {
+            ("git-hook", Some(_)) => setup::git_hook::remove_hook(),
+            ("intellij", Some(_)) => setup::intellij::remove_rustc_src(),
+            _ => {},
+        },
         ("serve", Some(matches)) => {
             let port = matches.value_of("port").unwrap().parse().unwrap();
             let lint = matches.value_of("lint");
@@ -48,6 +61,7 @@ fn main() {
 
 fn get_clap_config<'a>() -> ArgMatches<'a> {
     App::new("Clippy developer tooling")
+        .setting(AppSettings::ArgRequiredElseHelp)
         .subcommand(
             SubCommand::with_name("bless")
                 .about("bless the test output changes")
@@ -140,16 +154,42 @@ fn get_clap_config<'a>() -> ArgMatches<'a> {
                 .about("Ensures that stderr files do not grow longer than a certain amount of lines."),
         )
         .subcommand(
-            SubCommand::with_name("ide_setup")
+            SubCommand::with_name("setup")
-                .about("Alter dependencies so Intellij Rust can find rustc internals")
+                .about("Support for setting up your personal development environment")
-                .arg(
+                .setting(AppSettings::ArgRequiredElseHelp)
-                    Arg::with_name("rustc-repo-path")
+                .subcommand(
-                        .long("repo-path")
+                    SubCommand::with_name("intellij")
-                        .short("r")
+                        .about("Alter dependencies so Intellij Rust can find rustc internals")
-                        .help("The path to a rustc repo that will be used for setting the dependencies")
+                        .arg(
-                        .takes_value(true)
+                            Arg::with_name("rustc-repo-path")
-                        .value_name("path")
+                                .long("repo-path")
-                        .required(true),
+                                .short("r")
+                                .help("The path to a rustc repo that will be used for setting the dependencies")
+                                .takes_value(true)
+                                .value_name("path")
+                                .required(true),
+                        ),
+                )
+                .subcommand(
+                    SubCommand::with_name("git-hook")
+                        .about("Add a pre-commit git hook that formats your code to make it look pretty")
+                        .arg(
+                            Arg::with_name("force-override")
+                                .long("force-override")
+                                .short("f")
+                                .help("Forces the override of an existing git pre-commit hook")
+                                .required(false),
+                        ),
+                ),
+        )
+        .subcommand(
+            SubCommand::with_name("remove")
+                .about("Support for undoing changes done by the setup command")
+                .setting(AppSettings::ArgRequiredElseHelp)
+                .subcommand(SubCommand::with_name("git-hook").about("Remove any existing pre-commit git hook"))
+                .subcommand(
+                    SubCommand::with_name("intellij")
+                        .about("Removes rustc source paths added via `cargo dev setup intellij`"),
                 ),
         )
         .subcommand(

clippy_dev/src/setup/git_hook.rs

@@ -0,0 +1,79 @@
+use std::fs;
+use std::path::Path;
+
+/// Rusts setup uses `git rev-parse --git-common-dir` to get the root directory of the repo.
+/// I've decided against this for the sake of simplicity and to make sure that it doesn't install
+/// the hook if `clippy_dev` would be used in the rust tree. The hook also references this tool
+/// for formatting and should therefor only be used in a normal clone of clippy
+const REPO_GIT_DIR: &str = ".git";
+const HOOK_SOURCE_FILE: &str = "util/etc/pre-commit.sh";
+const HOOK_TARGET_FILE: &str = ".git/hooks/pre-commit";
+
+pub fn install_hook(force_override: bool) {
+    if !check_precondition(force_override) {
+        return;
+    }
+
+    // So a little bit of a funny story. Git on unix requires the pre-commit file
+    // to have the `execute` permission to be set. The Rust functions for modifying
+    // these flags doesn't seem to work when executed with normal user permissions.
+    //
+    // However, there is a little hack that is also being used by Rust itself in their
+    // setup script. Git saves the `execute` flag when syncing files. This means
+    // that we can check in a file with execution permissions and the sync it to create
+    // a file with the flag set. We then copy this file here. The copy function will also
+    // include the `execute` permission.
+    match fs::copy(HOOK_SOURCE_FILE, HOOK_TARGET_FILE) {
+        Ok(_) => {
+            println!("info: the hook can be removed with `cargo dev remove git-hook`");
+            println!("git hook successfully installed");
+        },
+        Err(err) => eprintln!(
+            "error: unable to copy `{}` to `{}` ({})",
+            HOOK_SOURCE_FILE, HOOK_TARGET_FILE, err
+        ),
+    }
+}
+
+fn check_precondition(force_override: bool) -> bool {
+    // Make sure that we can find the git repository
+    let git_path = Path::new(REPO_GIT_DIR);
+    if !git_path.exists() || !git_path.is_dir() {
+        eprintln!("error: clippy_dev was unable to find the `.git` directory");
+        return false;
+    }
+
+    // Make sure that we don't override an existing hook by accident
+    let path = Path::new(HOOK_TARGET_FILE);
+    if path.exists() {
+        if force_override {
+            return delete_git_hook_file(path);
+        }
+
+        eprintln!("error: there is already a pre-commit hook installed");
+        println!("info: use the `--force-override` flag to override the existing hook");
+        return false;
+    }
+
+    true
+}
+
+pub fn remove_hook() {
+    let path = Path::new(HOOK_TARGET_FILE);
+    if path.exists() {
+        if delete_git_hook_file(path) {
+            println!("git hook successfully removed");
+        }
+    } else {
+        println!("no pre-commit hook was found");
+    }
+}
+
+fn delete_git_hook_file(path: &Path) -> bool {
+    if let Err(err) = fs::remove_file(path) {
+        eprintln!("error: unable to delete existing pre-commit git hook ({})", err);
+        false
+    } else {
+        true
+    }
+}

clippy_dev/src/setup/intellij.rs

@@ -0,0 +1,223 @@
+use std::fs;
+use std::fs::File;
+use std::io::prelude::*;
+use std::path::{Path, PathBuf};
+
+// This module takes an absolute path to a rustc repo and alters the dependencies to point towards
+// the respective rustc subcrates instead of using extern crate xyz.
+// This allows IntelliJ to analyze rustc internals and show proper information inside Clippy
+// code. See https://github.com/rust-lang/rust-clippy/issues/5514 for details
+
+const RUSTC_PATH_SECTION: &str = "[target.'cfg(NOT_A_PLATFORM)'.dependencies]";
+const DEPENDENCIES_SECTION: &str = "[dependencies]";
+
+const CLIPPY_PROJECTS: &[ClippyProjectInfo] = &[
+    ClippyProjectInfo::new("root", "Cargo.toml", "src/driver.rs"),
+    ClippyProjectInfo::new("clippy_lints", "clippy_lints/Cargo.toml", "clippy_lints/src/lib.rs"),
+    ClippyProjectInfo::new("clippy_utils", "clippy_utils/Cargo.toml", "clippy_utils/src/lib.rs"),
+];
+
+/// Used to store clippy project information to later inject the dependency into.
+struct ClippyProjectInfo {
+    /// Only used to display information to the user
+    name: &'static str,
+    cargo_file: &'static str,
+    lib_rs_file: &'static str,
+}
+
+impl ClippyProjectInfo {
+    const fn new(name: &'static str, cargo_file: &'static str, lib_rs_file: &'static str) -> Self {
+        Self {
+            name,
+            cargo_file,
+            lib_rs_file,
+        }
+    }
+}
+
+pub fn setup_rustc_src(rustc_path: &str) {
+    let rustc_source_dir = match check_and_get_rustc_dir(rustc_path) {
+        Ok(path) => path,
+        Err(_) => return,
+    };
+
+    for project in CLIPPY_PROJECTS {
+        if inject_deps_into_project(&rustc_source_dir, project).is_err() {
+            return;
+        }
+    }
+
+    println!("info: the source paths can be removed again with `cargo dev remove intellij`");
+}
+
+fn check_and_get_rustc_dir(rustc_path: &str) -> Result<PathBuf, ()> {
+    let mut path = PathBuf::from(rustc_path);
+
+    if path.is_relative() {
+        match path.canonicalize() {
+            Ok(absolute_path) => {
+                println!("info: the rustc path was resolved to: `{}`", absolute_path.display());
+                path = absolute_path;
+            },
+            Err(err) => {
+                eprintln!("error: unable to get the absolute path of rustc ({})", err);
+                return Err(());
+            },
+        };
+    }
+
+    let path = path.join("compiler");
+    println!("info: looking for compiler sources at: {}", path.display());
+
+    if !path.exists() {
+        eprintln!("error: the given path does not exist");
+        return Err(());
+    }
+
+    if !path.is_dir() {
+        eprintln!("error: the given path is not a directory");
+        return Err(());
+    }
+
+    Ok(path)
+}
+
+fn inject_deps_into_project(rustc_source_dir: &Path, project: &ClippyProjectInfo) -> Result<(), ()> {
+    let cargo_content = read_project_file(project.cargo_file)?;
+    let lib_content = read_project_file(project.lib_rs_file)?;
+
+    if inject_deps_into_manifest(rustc_source_dir, project.cargo_file, &cargo_content, &lib_content).is_err() {
+        eprintln!(
+            "error: unable to inject dependencies into {} with the Cargo file {}",
+            project.name, project.cargo_file
+        );
+        Err(())
+    } else {
+        Ok(())
+    }
+}
+
+/// `clippy_dev` expects to be executed in the root directory of Clippy. This function
+/// loads the given file or returns an error. Having it in this extra function ensures
+/// that the error message looks nice.
+fn read_project_file(file_path: &str) -> Result<String, ()> {
+    let path = Path::new(file_path);
+    if !path.exists() {
+        eprintln!("error: unable to find the file `{}`", file_path);
+        return Err(());
+    }
+
+    match fs::read_to_string(path) {
+        Ok(content) => Ok(content),
+        Err(err) => {
+            eprintln!("error: the file `{}` could not be read ({})", file_path, err);
+            Err(())
+        },
+    }
+}
+
+fn inject_deps_into_manifest(
+    rustc_source_dir: &Path,
+    manifest_path: &str,
+    cargo_toml: &str,
+    lib_rs: &str,
+) -> std::io::Result<()> {
+    // do not inject deps if we have already done so
+    if cargo_toml.contains(RUSTC_PATH_SECTION) {
+        eprintln!(
+            "warn: dependencies are already setup inside {}, skipping file",
+            manifest_path
+        );
+        return Ok(());
+    }
+
+    let extern_crates = lib_rs
+        .lines()
+        // only take dependencies starting with `rustc_`
+        .filter(|line| line.starts_with("extern crate rustc_"))
+        // we have something like "extern crate foo;", we only care about the "foo"
+        // extern crate rustc_middle;
+        //              ^^^^^^^^^^^^
+        .map(|s| &s[13..(s.len() - 1)]);
+
+    let new_deps = extern_crates.map(|dep| {
+        // format the dependencies that are going to be put inside the Cargo.toml
+        format!(
+            "{dep} = {{ path = \"{source_path}/{dep}\" }}\n",
+            dep = dep,
+            source_path = rustc_source_dir.display()
+        )
+    });
+
+    // format a new [dependencies]-block with the new deps we need to inject
+    let mut all_deps = String::from("[target.'cfg(NOT_A_PLATFORM)'.dependencies]\n");
+    new_deps.for_each(|dep_line| {
+        all_deps.push_str(&dep_line);
+    });
+    all_deps.push_str("\n[dependencies]\n");
+
+    // replace "[dependencies]" with
+    // [dependencies]
+    // dep1 = { path = ... }
+    // dep2 = { path = ... }
+    // etc
+    let new_manifest = cargo_toml.replacen("[dependencies]\n", &all_deps, 1);
+
+    // println!("{}", new_manifest);
+    let mut file = File::create(manifest_path)?;
+    file.write_all(new_manifest.as_bytes())?;
+
+    println!("info: successfully setup dependencies inside {}", manifest_path);
+
+    Ok(())
+}
+
+pub fn remove_rustc_src() {
+    for project in CLIPPY_PROJECTS {
+        remove_rustc_src_from_project(project);
+    }
+}
+
+fn remove_rustc_src_from_project(project: &ClippyProjectInfo) -> bool {
+    let mut cargo_content = if let Ok(content) = read_project_file(project.cargo_file) {
+        content
+    } else {
+        return false;
+    };
+    let section_start = if let Some(section_start) = cargo_content.find(RUSTC_PATH_SECTION) {
+        section_start
+    } else {
+        println!(
+            "info: dependencies could not be found in `{}` for {}, skipping file",
+            project.cargo_file, project.name
+        );
+        return true;
+    };
+
+    let end_point = if let Some(end_point) = cargo_content.find(DEPENDENCIES_SECTION) {
+        end_point
+    } else {
+        eprintln!(
+            "error: the end of the rustc dependencies section could not be found in `{}`",
+            project.cargo_file
+        );
+        return false;
+    };
+
+    cargo_content.replace_range(section_start..end_point, "");
+
+    match File::create(project.cargo_file) {
+        Ok(mut file) => {
+            file.write_all(cargo_content.as_bytes()).unwrap();
+            println!("info: successfully removed dependencies inside {}", project.cargo_file);
+            true
+        },
+        Err(err) => {
+            eprintln!(
+                "error: unable to open file `{}` to remove rustc dependencies for {} ({})",
+                project.cargo_file, project.name, err
+            );
+            false
+        },
+    }
+}

clippy_dev/src/setup/mod.rs

@@ -0,0 +1,2 @@
+pub mod git_hook;
+pub mod intellij;

doc/basics.md

@@ -90,8 +90,10 @@ cargo dev fmt
 cargo dev update_lints
 # create a new lint and register it
 cargo dev new_lint
+# automatically formatting all code before each commit
+cargo dev setup git-hook
 # (experimental) Setup Clippy to work with IntelliJ-Rust
-cargo dev ide_setup
+cargo dev setup intellij
 ```
 
 ## lintcheck

util/etc/pre-commit.sh

@@ -0,0 +1,21 @@
+#!/bin/sh
+
+# hide output
+set -e
+
+# Update lints
+cargo dev update_lints
+git add clippy_lints/src/lib.rs
+
+# Formatting:
+#     Git will not automatically add the formatted code to the staged changes once
+#     fmt was executed. This collects all staged files rs files that are currently staged.
+#     They will later be added back.
+#
+#     This was proudly stolen and adjusted from here:
+#     https://medium.com/@harshitbangar/automatic-code-formatting-with-git-66c3c5c26798
+files=$( (git diff --cached --name-only --diff-filter=ACMR | grep -Ei "\.rs$") || true)
+if [ ! -z "${files}" ]; then
+    cargo dev fmt
+    git add $(echo "$files" | paste -s -d " " -)
+fi