feat(clap_complete): Support multi-values of positional argument with…

… `num_arg(N)`
clap-rs · Jul 26, 2024 · 788a1cc · 788a1cc
1 parent 076a138
commit 788a1cc
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Showing 2 changed files with 85 additions and 20 deletions.
diff --git a/clap_complete/src/dynamic/completer.rs b/clap_complete/src/dynamic/completer.rs
@@ -1,3 +1,4 @@
+use core::num;
 use std::ffi::OsStr;
 use std::ffi::OsString;
 
@@ -71,8 +72,37 @@ pub fn complete(
         }
 
         if is_escaped {
-            pos_index += 1;
-            state = ParseState::Pos(pos_index);
+            match state {
+                ParseState::ValueDone => {
+                    // Begin parsing a new positional argument after `--`.
+                    let num_args = parse_positional(current_cmd, pos_index);
+                    match num_args {
+                        Some(num_args) => {
+                            state = ParseState::Pos(1);
+                            if num_args <= 1 {
+                                pos_index += 1;
+                            }
+                        }
+                        None => {
+                            state = ParseState::ValueDone;
+                            pos_index += 1;
+                        }
+                    }
+                }
+                ParseState::Pos(num_arg) => {
+                    // HACK: Assuming `num_args` is fixed.
+                    let num_args = parse_positional(current_cmd, pos_index).unwrap_or(1);
+                    if num_arg + 1 < num_args {
+                        state = ParseState::Pos(num_arg + 1);
+                    } else {
+                        state = ParseState::Pos(1);
+                        pos_index += 1;
+                    }
+                }
+                ParseState::Opt(..) => {
+                    unreachable!("reason it won't be hit")
+                }
+            }
         } else if arg.is_escape() {
             is_escaped = true;
             state = ParseState::ValueDone;
@@ -124,9 +154,32 @@ pub fn complete(
             }
         } else {
             match state {
-                ParseState::ValueDone | ParseState::Pos(_) => {
-                    pos_index += 1;
-                    state = ParseState::ValueDone;
+                ParseState::ValueDone => {
+                    let num_args = parse_positional(current_cmd, pos_index);
+                    match num_args {
+                        Some(num_args) => {
+                            if num_args > 1 {
+                                state = ParseState::Pos(1);
+                            } else {
+                                state = ParseState::ValueDone;
+                                pos_index += 1;
+                            }
+                        }
+                        None => {
+                            state = ParseState::ValueDone;
+                            pos_index += 1;
+                        }
+                    }
+                }
+                ParseState::Pos(num_arg) => {
+                    // HACK: Assuming `num_args` is fixed.
+                    let num_args = parse_positional(current_cmd, pos_index).unwrap_or(1);
+                    if num_arg + 1 < num_args {
+                        state = ParseState::Pos(num_arg + 1);
+                    } else {
+                        state = ParseState::ValueDone;
+                        pos_index += 1;
+                    }
                 }
                 ParseState::Opt((ref opt, count)) => match opt.get_num_args() {
                     Some(range) => {
@@ -156,7 +209,7 @@ enum ParseState {
     /// Parsing a value done, there is no state to record.
     ValueDone,
 
-    /// Parsing a positional argument after `--`
+    /// Parsing a positional argument after `--`. Pos(takes_num_args)
     Pos(usize),
 
     /// Parsing a optional flag argument
@@ -603,6 +656,13 @@ fn parse_shortflags<'s>(
     (leading_flags, takes_value_opt.cloned(), short)
 }
 
+fn parse_positional(cmd: &clap::Command, pos_index: usize) -> Option<usize> {
+    let pos_arg = cmd
+        .get_positionals()
+        .find(|p| p.get_index() == Some(pos_index));
+    pos_arg.and_then(|a| a.get_num_args().and_then(|r| Some(r.max_values())))
+}
+
 /// A completion candidate definition
 ///
 /// This makes it easier to add more fields to completion candidate,

diff --git a/clap_complete/tests/testsuite/dynamic.rs b/clap_complete/tests/testsuite/dynamic.rs
@@ -609,20 +609,18 @@ fn suggest_multi_positional() {
     assert_data_eq!(
         complete!(cmd, "pos_a [TAB]"),
         snapbox::str![
-            "--format
---help\tPrint help
--F
--h\tPrint help"
+            "pos_a
+pos_b
+pos_c"
         ]
     );
 
     assert_data_eq!(
         complete!(cmd, "pos_a pos_b [TAB]"),
         snapbox::str![
-            "--format
---help\tPrint help
--F
--h\tPrint help"
+            "pos_a
+pos_b
+pos_c"
         ]
     );
 
@@ -642,10 +640,9 @@ pos_c"
     assert_data_eq!(
         complete!(cmd, "--format json pos_a [TAB]"),
         snapbox::str![
-            "--format
---help\tPrint help
--F
--h\tPrint help"
+            "pos_a
+pos_b
+pos_c"
         ]
     );
 
@@ -661,12 +658,20 @@ pos_c"
 
     assert_data_eq!(
         complete!(cmd, "--format json -- pos_a [TAB]"),
-        snapbox::str![""]
+        snapbox::str![
+            "pos_a
+pos_b
+pos_c"
+        ]
     );
 
     assert_data_eq!(
         complete!(cmd, "--format json -- pos_a pos_b [TAB]"),
-        snapbox::str![""]
+        snapbox::str![
+            "pos_a
+pos_b
+pos_c"
+        ]
     );
 
     assert_data_eq!(