Merge nucleic/clever-quartz-marten-uqnx into dev

brush-interactive/src/input_backend.rs

@@ -49,3 +49,24 @@ pub struct InteractivePrompt {
     /// Prompt to display on a continuation line of input.
     pub continuation_prompt: String,
 }
+
+/// Returns whether a parser result represents a complete command that can be
+/// executed, as opposed to a command that needs more physical input lines.
+pub(crate) fn parse_result_is_complete(
+    result: &Result<brush_parser::ast::Program, brush_parser::ParseError>,
+) -> bool {
+    match result {
+        // Unclosed quotes and similar tokenizer states need another line.
+        Err(brush_parser::ParseError::Tokenizing { inner, position: _ })
+            if inner.is_incomplete() =>
+        {
+            false
+        }
+        // An otherwise-valid compound command may simply be missing its
+        // closing token (`fi`, `done`, `}`, ...).
+        Err(brush_parser::ParseError::ParsingAtEndOfInput) => false,
+        // A located syntax error is complete input and should be surfaced.
+        // A successful parse is ready to execute.
+        _ => true,
+    }
+}