added --fix - fif can now rename files itself!

this alone warrants a bump to 0.4.0 imo, and now that i think about it, there's not really much keeping me from calling it 1.0...
i think i'd want to get more tests, and maybe upgrade to clap 3 stable when that happens, before calling it 1.0, though. maybe even get some sort of configuration file...

.gitignore

@@ -1,5 +1,6 @@
 /target
 /imgs
+/imgs.tar.zst
 /fif_*
 /old
 /.mypy_cache

CHANGELOG.md

@@ -5,6 +5,17 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## Unreleased
+### Added
+- `--fix` mode - instead of outputting a shell script or text file, fif will rename the misnamed files for you!
+  - By default, the user will be prompted for each rename. This behaviour can be changed with the new `p`/`--prompt`
+    flag: `-p always` to be prompted each time (the default), `-p error` to be prompted on errors and when a file
+    would be overwritten by renaming, and `-p never` to disable prompting altogether - this behaves the same as
+    answering "yes" to every prompt.
+  - The `--overwrite` flag must be specified along with `--fix` in order for fif to process renames that would cause an
+    existing file to be overwritten. Without it, fif will never overwrite existing files, even with `-p always`.
+    **Caution**: If this flag is set in combination with `--prompt never`, fif will overwrite files **without asking**!
+  - For a more thorough breakdown of how these flags work, see [the corresponding wiki
+    page](https://gitlab.com/Lynnesbian/fif/-/wikis/Fix).
 ### Changed
 - Capped help output (`-h`/`--help`) width at 120 characters max
 - Output is now sorted by filename - specifically, errors will appear first, followed by files that fif is unable to 

src/findings.rs

@@ -23,6 +23,20 @@ pub struct Findings {
 	pub mime: Mime,
 }
 
+impl Findings {
+	pub fn recommended_extension(&self) -> Option<String> {
+		mime_extension_lookup(self.mime.essence_str().into()).map(|extensions| extensions[0].clone())
+	}
+
+	pub fn recommended_path(&self) -> Option<PathBuf> {
+		if let Some(ext) = self.recommended_extension() {
+			Some(self.file.with_extension(ext.as_str()))
+		} else {
+			None
+		}
+	}
+}
+
 impl PartialOrd<Self> for Findings {
 	fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(self.cmp(other)) }
 }
@@ -61,12 +75,6 @@ impl serde::Serialize for Findings {
 	}
 }
 
-impl Findings {
-	pub fn recommended_extension(&self) -> Option<String> {
-		mime_extension_lookup(self.mime.essence_str().into()).map(|extensions| extensions[0].clone())
-	}
-}
-
 #[derive(Debug, PartialEq, PartialOrd, Ord, Eq)]
 #[cfg_attr(feature = "json", derive(serde::Serialize))]
 #[cfg_attr(feature = "json", serde(tag = "type", content = "path"))]

src/formats.rs

@@ -142,8 +142,8 @@ pub trait FormatSteps {
 		}
 
 		for finding in findings {
-			if let Some(ext) = finding.recommended_extension() {
-				self.rename(f, finding.file.as_path(), &finding.file.with_extension(ext.as_str()))?;
+			if let Some(name) = finding.recommended_path() {
+				self.rename(f, finding.file.as_path(), &name)?;
 			} else {
 				self.no_known_extension(f, finding.file.as_path())?;
 			}

src/main.rs

@@ -17,14 +17,14 @@
 #![forbid(unsafe_code)]
 #![warn(trivial_casts, unused_lifetimes, unused_qualifications)]
 
-use std::io::{stdout, BufWriter, Write};
+use std::io::{stdin, stdout, BufWriter, Write};
 use std::process::exit;
 
 use cfg_if::cfg_if;
 use clap::Clap;
 use fif::files::{scan_directory, scan_from_walkdir};
 use fif::formats::Format;
-use fif::parameters::OutputFormat;
+use fif::parameters::{OutputFormat, Prompt};
 use fif::utils::{os_name, CLAP_LONG_VERSION};
 use fif::{formats, parameters};
 use itertools::Itertools;
@@ -136,6 +136,69 @@ fn main() {
 		.collect_vec();
 
 	if args.fix {
+		fn ask(message: String) -> bool {
+			let mut buf = String::with_capacity(1);
+			print!("{} [y/N] ", message);
+
+			// flush stdout to ensure message is displayed
+			stdout().flush().expect("Failed to flush stdout");
+
+			if let Err(e) = stdin().read_line(&mut buf) {
+				// something went wrong while reading input - just exit
+				error!("{}", e);
+				exit(exitcode::IOERR)
+			}
+			buf.starts_with("y") || buf.starts_with("Y")
+		}
+
+		let prompt = args.prompt.unwrap_or(Prompt::Always);
+
+		for f in findings {
+			if let Some(rename_to) = f.recommended_path() {
+				let will_rename = {
+					if !args.overwrite && rename_to.exists() {
+						// handles: --prompt never, --prompt error, --prompt always
+						// user didn't specify --overwrite, and the destination exists
+						info!("Not renaming {:#?}: Target {:#?} exists", f.file, rename_to);
+						false
+					} else if prompt == Prompt::Never {
+						// handles: --prompt never --overwrite
+						// user specified --prompt never in conjunction with --overwrite, so always rename
+						true
+					} else if prompt == Prompt::Error || ask(format!("Rename {:#?} to {:#?}?", &f.file, &rename_to)) {
+						// handles: --prompt error --overwrite, --prompt always --overwrite [y]
+						// if the target exists, prompt before renaming; otherwise, just rename
+						!rename_to.exists() || ask(format!("Destination {:#?} already exists, overwrite?", rename_to))
+					} else {
+						// handles: --prompt always --overwrite [n]
+						// user was prompted and replied "no"
+						false
+					}
+				};
+
+				if !will_rename { continue }
+
+				loop {
+					match std::fs::rename(&f.file, &rename_to) {
+						Ok(_) => {
+							info!("Renamed {:#?} -> {:#?}", f.file, rename_to);
+							break;
+						}
+						Err(e) => {
+							warn!("Couldn't rename {:#?} to {:#?}: {:#?}", f.file, rename_to, e);
+							// if the user passed --prompt never, continue to the next file
+							// otherwise, prompt user to retry move, retrying until the rename succeeds or they respond "N"
+							if prompt == Prompt::Never || !ask(format!("Error while renaming file: {:#?}. Try again?", e)) {
+								break;
+							}
+						}
+					}
+				}
+			} else {
+				// no recommended name :c
+				info!("No known extension for file {:#?} of type {}", f.file, f.mime)
+			}
+		}
 	} else {
 		let mut buffered_stdout = BufWriter::new(stdout());
 

src/parameters.rs

@@ -32,6 +32,13 @@ pub enum OutputFormat {
 	Json,
 }
 
+#[derive(Clap, PartialEq, Debug)]
+pub enum Prompt {
+	Never,
+	Error,
+	Always
+}
+
 #[derive(Clap, Debug)]
 #[allow(clippy::struct_excessive_bools)]
 #[clap(
@@ -48,12 +55,18 @@ pub enum OutputFormat {
 	max_term_width = 120
 )]
 pub struct Parameters {
-	/// Automatically rename files to use the correct extension.
+	/// Automatically rename files to use the correct extension, prompting the user for every rename.
 	#[clap(long)]
 	pub fix: bool,
 
-	#[clap(long)]
-	pub noconfirm: bool,
+	/// Requires --fix. Should fif prompt you `Never`, only on `Error`s and overwrites, or `Always`?
+	#[clap(short = 'p', long, arg_enum, requires = "fix")]
+	pub prompt: Option<Prompt>,
+
+	/// Requires --fix. Allow overwriting files. Warning: When used in combination with `--prompt never`, fif will
+	/// overwrite files without prompting!
+	#[clap(short = 'n', long, requires = "fix")]
+	pub overwrite: bool,
 
 	// NOTE: clap's comma-separated argument parser makes it impossible to specify extensions with commas in their name -
 	// `-e sil\,ly` is treated as ["sil", "ly"] rather than as ["silly"], no matter how i escape the comma (in bash,

src/tests/mod.rs

@@ -136,6 +136,11 @@ fn simple_directory() {
 			assert_eq!(result.mime, IMAGE_PNG);
 			// 3. ensure the recommended extension for "wrong.jpg" is "png"
 			assert_eq!(&result.recommended_extension().unwrap(), &String::from("png"));
+			// 4. ensure the recommended filename for "wrong.jpg" is "wrong.png"
+			assert_eq!(
+				result.recommended_path().unwrap().file_name(),
+				Some(OsStr::new("wrong.png"))
+			);
 			continue;
 		}
 
@@ -146,6 +151,15 @@ fn simple_directory() {
 			.unwrap()
 			.contains(&result.recommended_extension().unwrap()));
 
+		// ensure that the recommended_name function outputs something beginning with "test"
+		assert!(result
+			.recommended_path()
+			.unwrap()
+			.file_name()
+			.unwrap()
+			.to_string_lossy()
+			.starts_with("test"));
+
 		// make sure the guessed mimetype is correct based on the extension of the scanned file
 		// because we already know that the extensions match the mimetype (as we created these files ourselves earlier in
 		// the test), all files with the "jpg" extension should be IMAGE_JPEGs, etc.