enhancement(remap): Support identifiers with leading numeric characters as fields in path

docs/reference/remap/expressions/path.cue

@@ -87,8 +87,8 @@ remap: expressions: path: {
 						title: "Valid path characters"
 						description: """
 							Path segments only allow for underscores and ASCII alpha-numeric characters
-							(`[a-zA-Z0-9_]`). Segments must be delimited with periods (`.`). If a segment contains
-							characters outside of this list it must be quoted.
+							(`[a-zA-Z0-9_]`) where integers like `0` are not supported. Quoting
+							can be used to escape these constraints.
 							"""
 					}
 				}

lib/vrl/parser/src/lex.rs

@@ -908,7 +908,13 @@ impl<'input> Lexer<'input> {
     fn numeric_literal(&mut self, start: usize) -> SpannedResult<'input, usize> {
         let (end, int) = self.take_while(start, |ch| is_digit(ch) || ch == '_');
 
+        let negative = self.input.get(start..start + 1) == Some("-");
         match self.peek() {
+            Some((_, ch)) if is_ident_continue(ch) && !negative => {
+                self.bump();
+                let (end, ident) = self.take_while(start, is_ident_continue);
+                Ok((start, Token::ident(ident), end))
+            }
             Some((_, '.')) => {
                 self.bump();
                 let (end, float) = self.take_while(start, |ch| is_digit(ch) || ch == '_');
@@ -1724,6 +1730,26 @@ mod test {
         );
     }
 
+    #[test]
+    fn queries_digit_path() {
+        test(
+            data(r#".0foo foo.00_7bar.tar"#),
+            vec![
+                (r#"~                    "#, LQuery),
+                (r#"~                    "#, Dot),
+                (r#" ~~~~                "#, Identifier("0foo")),
+                (r#"    ~                "#, RQuery),
+                (r#"      ~              "#, LQuery),
+                (r#"      ~~~            "#, Identifier("foo")),
+                (r#"         ~           "#, Dot),
+                (r#"          ~~~~~~~    "#, Identifier("00_7bar")),
+                (r#"                 ~   "#, Dot),
+                (r#"                  ~~~"#, Identifier("tar")),
+                (r#"                    ~"#, RQuery),
+            ],
+        );
+    }
+
     #[test]
     fn queries_nested_delims() {
         use StringLiteral as S;

lib/vrl/tests/tests/expressions/query/coalesce.vrl

@@ -0,0 +1,4 @@
+# result: 2
+
+foo = { "0bar": 2 }
+foo.(a | 0bar)

lib/vrl/tests/tests/expressions/query/mixed.vrl

@@ -5,8 +5,8 @@
     {
         "foo": [
             {
-                "bar": parse_json!("{ \"baz\": true }").baz,
+                "bar": parse_json!("{ \"baz\": {\"0tar\": true} }").baz,
             }
         ]
     }
-][1].foo[0].bar
+][1].foo[0].bar.0tar