make Options::apply fallible

README.md

@@ -67,11 +67,12 @@ struct Settings {
 // To implement `Options`, we only need to provide the `apply` method.
 // The `parse` method will be automatically generated.
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Caps => self.caps = true,
             Arg::ExclamationMarks(n) => self.exclamation_marks += n,
         }
+        Ok(())
     }
 }
 

docs/guide/port.md

@@ -94,10 +94,11 @@ enum Arg {
 struct Settings { a: bool }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::A => self.a = true,
         }
+        Ok(())
     }
 }
 
@@ -137,10 +138,11 @@ impl Default for Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::A => self.a = false,
         }
+        Ok(())
     }
 }
 
@@ -175,10 +177,11 @@ enum Arg {
 struct Settings { a: u8 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::A => self.a += 1,
         }
+        Ok(())
     }
 }
 
@@ -215,10 +218,11 @@ enum Arg {
 struct Settings { a: OsString }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::A(s) => self.a = s,
         }
+        Ok(())
     }
 }
 
@@ -255,10 +259,11 @@ enum Arg {
 struct Settings { a: Vec<OsString> }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::A(s) => self.a.push(s),
         }
+        Ok(())
     }
 }
 
@@ -271,4 +276,4 @@ let a = Settings::default().parse(std::env::args_os()).unwrap().0.a;
 [Up](super)
 [Next](next)
 
-</div>
+</div>

docs/guide/quick.md

@@ -59,10 +59,11 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Force => self.force = true,
         }
+        Ok(())
     }
 }
 
@@ -100,11 +101,12 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Force => self.force = true,
             Arg::NoForce => self.force = false,
         }
+        Ok(())
     }
 }
 
@@ -160,10 +162,11 @@ enum Arg {
 # }
 #
 # impl Options<Arg> for Settings {
-#     fn apply(&mut self, arg: Arg) {
+#     fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
 #         match arg {
 #             Arg::Name(name) => self.name = name,
 #         }
+#         Ok(())
 #     }
 # }
 #
@@ -197,10 +200,11 @@ enum Arg {
 # }
 #
 # impl Options<Arg> for Settings {
-#     fn apply(&mut self, arg: Arg) {
+#     fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
 #         match arg {
 #             Arg::Name(name) => self.name = name,
 #         }
+#         Ok(())
 #     }
 # }
 #
@@ -234,10 +238,11 @@ enum Arg {
 # }
 #
 # impl Options<Arg> for Settings {
-#     fn apply(&mut self, arg: Arg) {
+#     fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
 #         match arg {
 #             Arg::Force(b) => self.force = b,
 #         }
+#         Ok(())
 #     }
 # }
 #
@@ -269,10 +274,11 @@ enum Arg {
 # }
 #
 # impl Options<Arg> for Settings {
-#     fn apply(&mut self, arg: Arg) {
+#     fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
 #         match arg {
 #             Arg::Sort(s) => self.sort = s,
 #         }
+#         Ok(())
 #     }
 # }
 #
@@ -287,4 +293,4 @@ enum Arg {
 [Up](super)
 [Next](next)
 
-</div>
+</div>

examples/completion.rs

@@ -33,7 +33,7 @@ enum Arg {
 struct Settings;
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, _arg: Arg) {
+    fn apply(&mut self, _arg: Arg) -> Result<(), uutils_args::Error> {
         panic!("Compile with the 'parse-is-complete' feature!")
     }
 }

examples/deprecated.rs

@@ -34,11 +34,12 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Min(n) => self.n1 = n,
             Arg::Plus(n) => self.n2 = n,
         }
+        Ok(())
     }
 }
 

examples/hello_world.rs

@@ -22,12 +22,13 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Name(n) => self.name = n,
             Arg::Count(c) => self.count = c,
             Arg::Hidden => {}
         }
+        Ok(())
     }
 }
 

examples/value.rs

@@ -25,10 +25,11 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Color(c) => self.color = c,
         }
+        Ok(())
     }
 }
 

src/lib.rs

@@ -166,7 +166,7 @@ impl<T: Arguments> ArgumentIter<T> {
 /// call [`Options::apply`] on the result until the arguments are exhausted.
 pub trait Options<Arg: Arguments>: Sized {
     /// Apply a single argument to the options.
-    fn apply(&mut self, arg: Arg);
+    fn apply(&mut self, arg: Arg) -> Result<(), Error>;
 
     /// Parse an iterator of arguments into the options
     #[allow(unused_mut)]
@@ -191,7 +191,7 @@ pub trait Options<Arg: Arguments>: Sized {
         {
             let mut iter = ArgumentIter::<Arg>::from_args(args);
             while let Some(arg) = iter.next_arg()? {
-                self.apply(arg);
+                self.apply(arg)?;
             }
             Ok((self, iter.positional_arguments))
         }

tests/coreutils/b2sum.rs

@@ -46,7 +46,7 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Binary => self.binary = true,
             Arg::Check => self.check = true,
@@ -57,6 +57,7 @@ impl Options<Arg> for Settings {
             Arg::Strict => self.strict = true,
             Arg::Warn => self.check_output = CheckOutput::Warn,
         }
+        Ok(())
     }
 }
 

tests/coreutils/base32.rs

@@ -34,13 +34,14 @@ impl Default for Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Decode => self.decode = true,
             Arg::IgnoreGarbage => self.ignore_garbage = true,
             Arg::Wrap(0) => self.wrap = None,
             Arg::Wrap(x) => self.wrap = Some(x),
         }
+        Ok(())
     }
 }
 

tests/coreutils/basename.rs

@@ -26,7 +26,7 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Multiple => self.multiple = true,
             Arg::Suffix(s) => {
@@ -35,6 +35,7 @@ impl Options<Arg> for Settings {
             }
             Arg::Zero => self.zero = true,
         }
+        Ok(())
     }
 }
 

tests/coreutils/cat.rs

@@ -48,7 +48,7 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::ShowAll => {
                 self.show_tabs = true;
@@ -70,6 +70,7 @@ impl Options<Arg> for Settings {
             Arg::NumberNonblank => self.number = NumberingMode::NonEmpty,
             Arg::SqueezeBlank => self.squeeze_blank = true,
         }
+        Ok(())
     }
 }
 

tests/coreutils/cksum.rs

@@ -30,7 +30,7 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Binary => self.binary = Tristate::True,
             Arg::Text => self.binary = Tristate::False,
@@ -47,6 +47,7 @@ impl Options<Arg> for Settings {
                 self.tag = Tristate::False;
             }
         }
+        Ok(())
     }
 }
 

tests/coreutils/dd.rs

@@ -92,7 +92,7 @@ impl Default for Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Infile(f) => self.infile = Some(f),
             Arg::Outfile(f) => self.outfile = Some(f),
@@ -111,6 +111,7 @@ impl Options<Arg> for Settings {
             Arg::Iflag(_f) => todo!(),
             Arg::Oflag(_f) => todo!(),
         }
+        Ok(())
     }
 }
 

tests/coreutils/echo.rs

@@ -24,12 +24,13 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::NoNewline => self.trailing_newline = false,
             Arg::EnableEscape => self.escape = true,
             Arg::DisableEscape => self.escape = false,
         }
+        Ok(())
     }
 }
 

tests/coreutils/head.rs

@@ -188,7 +188,7 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Bytes(n) => {
                 self.mode = Mode::Bytes;
@@ -202,6 +202,7 @@ impl Options<Arg> for Settings {
             Arg::Verbose => self.verbose = true,
             Arg::Zero => self.zero = true,
         }
+        Ok(())
     }
 }
 

tests/coreutils/ls.rs

@@ -360,7 +360,7 @@ impl Default for Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::All => self.which_files = Files::All,
             Arg::AlmostAll => self.which_files = Files::AlmostAll,
@@ -417,6 +417,7 @@ impl Options<Arg> for Settings {
             }
             Arg::GroupDirectoriesFirst => self.group_directories_first = true,
         }
+        Ok(())
     }
 }
 

tests/coreutils/mktemp.rs

@@ -40,7 +40,7 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Directory => self.directory = true,
             Arg::DryRun => self.dry_run = true,
@@ -49,6 +49,7 @@ impl Options<Arg> for Settings {
             Arg::TreatAsTemplate => self.treat_as_template = true,
             Arg::TmpDir(dir) => self.tmp_dir = Some(dir),
         }
+        Ok(())
     }
 }
 

tests/coreutils/shuf.rs

@@ -23,11 +23,12 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Echo => self.echo = true,
             Arg::Zero => self.zero = true,
         }
+        Ok(())
     }
 }
 

tests/coreutils/tail.rs

@@ -244,7 +244,7 @@ struct Settings {
 }
 
 impl Options<Arg> for Settings {
-    fn apply(&mut self, arg: Arg) {
+    fn apply(&mut self, arg: Arg) -> Result<(), uutils_args::Error> {
         match arg {
             Arg::Bytes(n) => {
                 self.mode = Mode::Bytes;
@@ -268,6 +268,7 @@ impl Options<Arg> for Settings {
             Arg::Zero => self.zero = true,
             Arg::PresumeInputPipe => self.presume_input_pipe = true,
         }
+        Ok(())
     }
 }