fix clippy help text, check for clippy-driver

src/bin/cargo/commands/clippy.rs

@@ -6,7 +6,7 @@ pub fn cli() -> App {
     subcommand("clippy-preview")
         // subcommand aliases are handled in aliased_command()
         // .alias("c")
-        .about("Check a local package and all of its dependencies for errors")
+        .about("Checks a package to catch common mistakes and improve your Rust code.")
         .arg_package_spec(
             "Package(s) to check",
             "Check all packages in the workspace",
@@ -49,6 +49,18 @@ the `--release` flag will use the `release` profile instead.
 
 The `--profile test` flag can be used to check unit tests with the
 `#[cfg(test)]` attribute.
+
+To allow or deny a lint from the command line you can use `cargo clippy --`
+with:
+
+    -W --warn OPT       Set lint warnings
+    -A --allow OPT      Set lint allowed
+    -D --deny OPT       Set lint denied
+    -F --forbid OPT     Set lint forbidden
+
+You can use tool lints to allow or deny lints from your code, eg.:
+
+    #[allow(clippy::needless_lifetimes)]
 ",
         )
 }

src/bin/cargo/main.rs

@@ -7,9 +7,10 @@
 use std::collections::BTreeSet;
 use std::env;
 use std::fs;
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
 
 use cargo::core::shell::Shell;
+use cargo::util::paths::is_executable;
 use cargo::util::{self, command_prelude, lev_distance, CargoResult, CliResult, Config};
 use cargo::util::{CliError, ProcessError};
 
@@ -164,20 +165,6 @@ fn execute_external_subcommand(config: &Config, cmd: &str, args: &[&str]) -> Cli
     Err(CliError::new(err, 101))
 }
 
-#[cfg(unix)]
-fn is_executable<P: AsRef<Path>>(path: P) -> bool {
-    use std::os::unix::prelude::*;
-    fs::metadata(path)
-        .map(|metadata| metadata.is_file() && metadata.permissions().mode() & 0o111 != 0)
-        .unwrap_or(false)
-}
-#[cfg(windows)]
-fn is_executable<P: AsRef<Path>>(path: P) -> bool {
-    fs::metadata(path)
-        .map(|metadata| metadata.is_file())
-        .unwrap_or(false)
-}
-
 fn search_directories(config: &Config) -> Vec<PathBuf> {
     let mut dirs = vec![config.home().clone().into_path_unlocked().join("bin")];
     if let Some(val) = env::var_os("PATH") {

src/cargo/util/config.rs

@@ -20,6 +20,7 @@ use serde::Deserialize;
 use serde::{de, de::IntoDeserializer};
 use url::Url;
 
+use self::ConfigValue as CV;
 use crate::core::profiles::ConfigProfiles;
 use crate::core::shell::Verbosity;
 use crate::core::{CliUnstable, Shell, SourceId, Workspace};
@@ -30,7 +31,6 @@ use crate::util::Filesystem;
 use crate::util::Rustc;
 use crate::util::ToUrl;
 use crate::util::{paths, validate_package_name};
-use self::ConfigValue as CV;
 
 /// Configuration information for cargo. This is not specific to a build, it is information
 /// relating to cargo itself.
@@ -206,7 +206,16 @@ impl Config {
                 .into_path_unlocked()
         });
         let wrapper = if self.clippy_override {
-            Some(self.get_tool("clippy-driver")?)
+            let tool = self.get_tool("clippy-driver")?;
+            let tool = paths::resolve_executable(&tool).map_err(|e| {
+                failure::format_err!("{}: please run `rustup component add clippy`", e)
+            })?;
+            if !paths::is_executable(&tool) {
+                return Err(failure::format_err!(
+                    "found file for `clippy-driver` but its not an executable. what the heck is going on !? please run `rustup component add clippy`"
+                ));
+            }
+            Some(tool)
         } else {
             self.maybe_get_tool("rustc-wrapper")?
         };
@@ -407,6 +416,7 @@ impl Config {
         match self.get_env(key)? {
             Some(v) => Ok(Some(v)),
             None => {
+                // println!("{:#?}", self);
                 let config_key = key.to_config();
                 let o_cv = self.get_cv(&config_key)?;
                 match o_cv {
@@ -756,17 +766,14 @@ impl Config {
             } else {
                 PathBuf::from(tool_path)
             };
-            println!("some tool {}", tool);
             return Ok(Some(path));
         }
 
         let var = format!("build.{}", tool);
         if let Some(tool_path) = self.get_path(&var)? {
-            println!("some tool {}", tool);
             return Ok(Some(tool_path.val));
         }
 
-        println!("NO TOOL {}", tool);
         Ok(None)
     }
 
@@ -940,8 +947,7 @@ impl ConfigError {
     }
 }
 
-impl std::error::Error for ConfigError {
-}
+impl std::error::Error for ConfigError {}
 
 // Future note: currently, we cannot override `Fail::cause` (due to
 // specialization) so we have no way to return the underlying causes. In the

src/cargo/util/paths.rs

@@ -89,6 +89,20 @@ pub fn normalize_path(path: &Path) -> PathBuf {
     ret
 }
 
+#[cfg(unix)]
+pub fn is_executable<P: AsRef<Path>>(path: P) -> bool {
+    use std::os::unix::prelude::*;
+    fs::metadata(path)
+        .map(|metadata| metadata.is_file() && metadata.permissions().mode() & 0o111 != 0)
+        .unwrap_or(false)
+}
+#[cfg(windows)]
+pub fn is_executable<P: AsRef<Path>>(path: P) -> bool {
+    fs::metadata(path)
+        .map(|metadata| metadata.is_file())
+        .unwrap_or(false)
+}
+
 pub fn resolve_executable(exec: &Path) -> CargoResult<PathBuf> {
     if exec.components().count() == 1 {
         let paths = env::var_os("PATH").ok_or_else(|| failure::format_err!("no PATH"))?;