nicer output for fif -V and fif --version

.gitignore

@@ -8,4 +8,5 @@ fif_*
 !clippy.sh
 cargo-timing*.html
 todo.txt
-/pkg/*
+/pkg/*
+/out

.idea/fif.iml

@@ -10,6 +10,7 @@
       <excludeFolder url="file://$MODULE_DIR$/awful" />
       <excludeFolder url="file://$MODULE_DIR$/.mypy_cache" />
       <excludeFolder url="file://$MODULE_DIR$/pkg" />
+      <excludeFolder url="file://$MODULE_DIR$/out" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />

CHANGELOG.md

@@ -2,6 +2,13 @@
 Dates are given in YYYY-MM-DD format.
 
 ## v0.3
+### v0.3.2 (2021-mm-dd)
+#### Bugfixes
+- Fixed PowerShell output regression introduced in v0.2.13, whoops
+#### Other
+- Nicer version output: `fif -V` reports "fif v0.3.2" (instead of just "fif 0.3.2" without the "v"), and `fif --version`
+  reports `fif v0.3.2 (XDG-Mime backend)`, or whatever backend you're using.
+
 ### v0.3.1 (2021-07-06)
 #### Features
 - Added JSON output support via `-o json`

src/formats.rs

@@ -10,6 +10,7 @@ use cfg_if::cfg_if;
 use snailquote::escape;
 
 use crate::findings::ScanError;
+use crate::parameters::VERSION;
 use crate::{Findings, BACKEND};
 use itertools::Itertools;
 
@@ -49,9 +50,6 @@ macro_rules! writablesln {
 	};
 }
 
-/// The current version of fif, as defined in Cargo.toml.
-const VERSION: Option<&'static str> = option_env!("CARGO_PKG_VERSION");
-
 #[doc(hidden)]
 type Entries<'a> = [Result<Findings<'a>, ScanError<'a>>];
 

src/parameters.rs

@@ -1,8 +1,10 @@
 //! [Clap] struct used to parse command line arguments.
 
 use crate::string_type::String as StringType;
+use crate::BACKEND;
 use cfg_if::cfg_if;
 use clap::{AppSettings, Clap};
+use once_cell::sync::OnceCell;
 use std::collections::BTreeSet;
 use std::path::PathBuf;
 
@@ -14,6 +16,34 @@ cfg_if! {
 	}
 }
 
+/// The current version of fif, as defined in Cargo.toml.
+pub const VERSION: Option<&'static str> = option_env!("CARGO_PKG_VERSION");
+
+// the version and long_version given to clap need to be a &str, but we want to use format!, which returns a String.
+// we can't just do something like `version = format!(...).as_str()`, because clap needs to know that the version will
+// live for a given lifetime, which we need to satisfy by making our String static. of course, you can't use format!
+// statically, so we need to use a OnceCell or similar to get around this.
+static CLAP_VERSION: OnceCell<String> = OnceCell::new();
+static CLAP_LONG_VERSION: OnceCell<String> = OnceCell::new();
+
+/// Sets [`CLAP_VERSION`] to be the version defined in Cargo.toml, prefixed with a v (e.g. "v0.3.1"), then returns it as
+/// a String.
+fn clap_version() -> &'static str {
+	CLAP_VERSION
+		.set(format!("v{}", VERSION.unwrap_or("???")))
+		.unwrap_or_default(); // it doesn't matter if CLAP_VERSION has already been set
+	CLAP_VERSION.get().unwrap().as_str()
+}
+
+/// Sets [`CLAP_LONG_VERSION`] to be similar to [`CLAP_VERSION`], followed by the chosen backend in parentheses (e.g.
+/// "v0.3.1 (XDG-Mime backend)"), then returns it as a String.
+fn clap_long_version() -> &'static str {
+	CLAP_LONG_VERSION
+		.set(format!("v{} ({} backend)", VERSION.unwrap_or("???"), BACKEND))
+		.unwrap_or_default();
+	CLAP_LONG_VERSION.get().unwrap().as_str()
+}
+
 #[derive(Clap, PartialEq, Debug)]
 pub enum OutputFormat {
 	/// A Bourne shell compatible script.
@@ -33,7 +63,8 @@ pub enum OutputFormat {
 
 #[derive(Clap, Debug)]
 #[clap(
-	version = option_env!("CARGO_PKG_VERSION").unwrap_or("???"),
+	version = clap_version(),
+	long_version = clap_long_version(),
 	author = option_env!("CARGO_PKG_AUTHORS").unwrap_or("Lynnesbian"),
 	about = option_env!("CARGO_PKG_DESCRIPTION").unwrap_or("File Info Fixer"),
 	before_help = "Copyright © 2021 Lynnesbian under the GPL3 (or later) License.",