test(clap_complete): Add test cases for --flag bar and -f bar completion

clap_complete/tests/testsuite/dynamic.rs

@@ -1,5 +1,6 @@
 #![cfg(feature = "unstable-dynamic")]
 
+use std::fs;
 use std::path::Path;
 
 use clap::{builder::PossibleValue, Command};
@@ -9,7 +10,7 @@ macro_rules! complete {
     ($cmd:expr, $input:expr$(, current_dir = $current_dir:expr)? $(,)?) => {
         {
             #[allow(unused)]
-            let current_dir = None;
+            let current_dir: Option<&Path> = None;
             $(let current_dir = $current_dir;)?
             complete(&mut $cmd, $input, current_dir)
         }
@@ -288,6 +289,156 @@ goodbye-world
     );
 }
 
+#[test]
+fn suggest_argument_value() {
+    let mut cmd = Command::new("dynamic")
+        .arg(
+            clap::Arg::new("input")
+                .long("input")
+                .short('i')
+                .value_hint(clap::ValueHint::FilePath),
+        )
+        .arg(
+            clap::Arg::new("format")
+                .long("format")
+                .short('F')
+                .value_parser(["json", "yaml", "toml"]),
+        )
+        .arg(
+            clap::Arg::new("count")
+                .long("count")
+                .short('c')
+                .action(clap::ArgAction::Count),
+        )
+        .arg(clap::Arg::new("positional").value_parser(["pos_a", "pos_b", "pos_c"]))
+        .args_conflicts_with_subcommands(true);
+
+    let testdir = snapbox::dir::DirRoot::mutable_temp().unwrap();
+    let testdir_path = testdir.path().unwrap();
+
+    fs::write(testdir_path.join("a_file"), "").unwrap();
+    fs::write(testdir_path.join("b_file"), "").unwrap();
+    fs::create_dir_all(testdir_path.join("c_dir")).unwrap();
+    fs::create_dir_all(testdir_path.join("d_dir")).unwrap();
+
+    assert_data_eq!(
+        complete!(cmd, "--input [TAB]", current_dir = Some(testdir_path)),
+        snapbox::str![
+            "--input
+--format
+--count
+--help	Print help
+-i
+-F
+-c
+-h	Print help
+pos_a
+pos_b
+pos_c"
+        ],
+    );
+
+    assert_data_eq!(
+        complete!(cmd, "-i [TAB]", current_dir = Some(testdir_path)),
+        snapbox::str![
+            "--input
+--format
+--count
+--help	Print help
+-i
+-F
+-c
+-h	Print help
+pos_a
+pos_b
+pos_c"
+        ],
+    );
+
+    assert_data_eq!(
+        complete!(cmd, "--input a[TAB]", current_dir = Some(testdir_path)),
+        snapbox::str![""],
+    );
+
+    assert_data_eq!(
+        complete!(cmd, "-i b[TAB]", current_dir = Some(testdir_path)),
+        snapbox::str![""],
+    );
+
+    assert_data_eq!(
+        complete!(cmd, "--format [TAB]"),
+        snapbox::str![
+            "--input
+--format
+--count
+--help	Print help
+-i
+-F
+-c
+-h	Print help
+pos_a
+pos_b
+pos_c"
+        ],
+    );
+
+    assert_data_eq!(
+        complete!(cmd, "-F [TAB]"),
+        snapbox::str![
+            "--input
+--format
+--count
+--help	Print help
+-i
+-F
+-c
+-h	Print help
+pos_a
+pos_b
+pos_c"
+        ],
+    );
+
+    assert_data_eq!(complete!(cmd, "--format j[TAB]"), snapbox::str![""],);
+
+    assert_data_eq!(complete!(cmd, "-F j[TAB]"), snapbox::str![""],);
+
+    assert_data_eq!(complete!(cmd, "--format t[TAB]"), snapbox::str![""],);
+
+    assert_data_eq!(complete!(cmd, "-F t[TAB]"), snapbox::str![""],);
+
+    assert_data_eq!(
+        complete!(cmd, "-cccF [TAB]"),
+        snapbox::str![
+            "--input
+--format
+--count
+--help\tPrint help
+-i
+-F
+-c
+-h\tPrint help
+pos_a
+pos_b
+pos_c"
+        ]
+    );
+
+    assert_data_eq!(
+        complete!(cmd, "--input a_file [TAB]"),
+        snapbox::str![
+            "--input
+--format
+--count
+--help\tPrint help
+-i
+-F
+-c
+-h\tPrint help"
+        ]
+    );
+}
+
 fn complete(cmd: &mut Command, args: impl AsRef<str>, current_dir: Option<&Path>) -> String {
     let input = args.as_ref();
     let mut args = vec![std::ffi::OsString::from(cmd.get_name())];