Support fmt-like braced arguments (#112)

Author: lu-zero

src/formatter.rs

@@ -173,6 +173,7 @@ pub(crate) fn format(
                         .collect::<String>();
                     s.into()
                 }
+                TokenKind::Placeholder => format!("{} / {:?}", token.value, token.key).into(),
                 _ => Cow::Borrowed(token.value),
             };
             anstream::eprintln!("{k}{:21}{rk}: {d}{:50}{rd} {line}", kind, value);

src/lib.rs

@@ -1764,6 +1764,29 @@ mod tests {
         );
     }
 
+    #[test]
+    fn it_recognizes_braced_placeholders_with_param_values() {
+        let input = "SELECT {a}, {b}, {c};";
+        let params = vec![
+            ("a".to_string(), "first".to_string()),
+            ("b".to_string(), "second".to_string()),
+            ("c".to_string(), "third".to_string()),
+        ];
+        let options = FormatOptions::default();
+        let expected = indoc!(
+            "
+            SELECT
+              first,
+              second,
+              third;"
+        );
+
+        assert_eq!(
+            format(input, &QueryParams::Named(params), &options),
+            expected
+        );
+    }
+
     #[test]
     fn it_formats_query_with_go_batch_separator() {
         let input = "SELECT 1 GO SELECT 2";

src/tokenizer.rs

@@ -1,7 +1,7 @@
 use std::borrow::Cow;
 use unicode_categories::UnicodeCategories;
 use winnow::ascii::{digit0, digit1, till_line_ending, Caseless};
-use winnow::combinator::{alt, dispatch, eof, fail, opt, peek, terminated};
+use winnow::combinator::{alt, delimited, dispatch, eof, fail, opt, peek, terminated};
 use winnow::error::ContextError;
 use winnow::error::ParserError;
 use winnow::prelude::*;
@@ -326,13 +326,15 @@ fn get_placeholder_token<'i>(
             get_ident_named_placeholder_token,
             |input: &mut _| get_string_named_placeholder_token(input, dialect),
             get_indexed_placeholder_token,
+            get_braced_named_placeholder_token,
         ))
         .parse_next(input)
     } else {
         alt((
             get_indexed_placeholder_token,
             get_ident_named_placeholder_token,
             |input: &mut _| get_string_named_placeholder_token(input, dialect),
+            get_braced_named_placeholder_token,
         ))
         .parse_next(input)
     }
@@ -381,6 +383,25 @@ fn get_ident_named_placeholder_token<'i>(input: &mut &'i str) -> Result<Token<'i
         })
 }
 
+fn get_braced_named_placeholder_token<'i>(input: &mut &'i str) -> Result<Token<'i>> {
+    delimited(
+        '{',
+        take_while(1.., |c: char| c.is_alphanumeric() || c == '_'),
+        '}',
+    )
+    .with_taken()
+    .parse_next(input)
+    .map(|(index, token)| {
+        let index = Cow::Borrowed(index);
+        Token {
+            kind: TokenKind::Placeholder,
+            value: token,
+            key: Some(PlaceholderKind::Named(index)),
+            alias: token,
+        }
+    })
+}
+
 fn get_string_named_placeholder_token<'i>(
     input: &mut &'i str,
     dialect: Dialect,