refactor: improve CLI value parsing/docs (#208)

A follow-up to #204

- Allow boolean options to be treated as flags (no value passed) if
  their default value is `false` (`--file-changes-only`, `--step-summary`,
  `--*-review`, etc).
- Some other CLI options can now accept no value (like a flag) including
  `--verbosity`
- Use `std::str::FromStr` trait to parse the given `--version`:
   * if no value is given, then behave exactly like the `cpp-linter
     version` subcommand (print version and exit)
   * if a path is given look for clang-tools in that path. This only
     ensures the given path exists, not if the clang- tool is present; that
     is done later if the tool is needed.
   * expand support for version specifiers using `semver::VersionReq`. This
     removes the need for `lenient_semver` dependency and allows the user to
     specify a range of clang versions. For example, `>=14, <16`, `=12.0.1`,
     or simply `16` (would be treated as `=16`).
     See [`semver::VersionReq` docs][ver-req-docs] for more detail.
- adjust docs to better describe accepted/possible values.

Due to the changes in parsing the user-given `--version`, there is a new
enum, `ClangTool` that enforces type-safety about finding the clang
tools (when they are needed).

* Instead of passing the tool name (as a str), the `ClangTool` enum is
  used to avoid typos and convey explicit support for only clang-tidy and
  clang-format.
* Getting the clang tool's path and version are now instance methods of
  the `ClangTool` enum.

[ver-req-docs]:
https://docs.rs/semver/1.0.27/semver/struct.VersionReq.html

Author: 2bndy5

Cargo.lock

@@ -21,7 +21,6 @@ colored = "3.0.0"
 fast-glob = "1.0.0"
 futures = "0.3.31"
 git2 = "0.20.2"
-lenient_semver = "0.4.2"
 log = { version = "0.4.28", features = ["std"] }
 quick-xml = { version = "0.38.3", features = ["serialize"] }
 regex = "1.12.2"

cpp-linter/Cargo.toml

@@ -9,8 +9,8 @@ use std::{
     sync::{Arc, Mutex, MutexGuard},
 };
 
-use anyhow::{Context, Result};
 // non-std crates
+use anyhow::{Context, Result};
 use regex::Regex;
 use serde::Deserialize;
 
@@ -346,14 +346,15 @@ mod test {
     use std::{
         env,
         path::PathBuf,
+        str::FromStr,
         sync::{Arc, Mutex},
     };
 
     use regex::Regex;
 
     use crate::{
-        clang_tools::get_clang_tool_exe,
-        cli::{ClangParams, LinesChangedOnly},
+        clang_tools::ClangTool,
+        cli::{ClangParams, LinesChangedOnly, RequestedVersion},
         common_fs::FileObj,
     };
 
@@ -421,11 +422,14 @@ mod test {
 
     #[test]
     fn use_extra_args() {
-        let exe_path = get_clang_tool_exe(
-            "clang-tidy",
-            env::var("CLANG_VERSION").unwrap_or("".to_string()).as_str(),
-        )
-        .unwrap();
+        let exe_path = ClangTool::ClangTidy
+            .get_exe_path(
+                &RequestedVersion::from_str(
+                    env::var("CLANG_VERSION").unwrap_or("".to_string()).as_str(),
+                )
+                .unwrap(),
+            )
+            .unwrap();
         let file = FileObj::new(PathBuf::from("tests/demo/demo.cpp"));
         let arc_ref = Arc::new(Mutex::new(file));
         let extra_args = vec!["-std=c++17".to_string(), "-Wall".to_string()];