@@ -0,0 +1,88 @@
+//! Whether macro expansion would expand a call in one unexpanded SQL test body.
+
+use sqlbuild_core::text::main::is_python_space::is_python_space;
+use sqlbuild_sqltext::sql_scan::main::matching_paren::matching_paren;
+use sqlbuild_sqltext::sql_scan::main::non_code_end::non_code_end;
+use sqlbuild_sqltext::sql_scan::models::QuotePolicy;
+
+/// Declaration calls that expansion substitutes rather than running as macros.
+const DECLARATION_CALLS: [&str; 2] = ["enum", "const"];
+
+/// Whether expansion's call scanner finds a macro call; text it cannot scan leaves expansion to fail.
+pub(crate) fn calls_macro(sql: &str) -> bool {
+    if !sql.contains('@') {
+        return false;
+    }
+    let bytes = sql.as_bytes();
+    let mut index = 0;
+    while index < bytes.len() {
+        match non_code_end(bytes, index, QuotePolicy::COMPILER) {
+            Ok(Some(end)) => {
+                index = end;
+                continue;
+            }
+            Ok(None) => {}
+            Err(_) => return false,
+        }
+        if bytes[index] == b'@'
+            && let Some(open) = call_open(sql, index)
+        {
+            if !DECLARATION_CALLS.contains(&name_at(sql, index + 1)) {
+                return true;
+            }
+            let Ok(close) = matching_paren(bytes, open, QuotePolicy::COMPILER) else {
+                return false;
+            };
+            index = close + 1;
+            continue;
+        }
+        index += char_at(sql, index).map_or(1, char::len_utf8);
+    }
+    false
+}
+
+/// Python `_is_macro_call_start`, which also skips whitespace between name characters.
+fn call_open(sql: &str, at: usize) -> Option<usize> {
+    let first = char_at(sql, at + 1)?;
+    if !(first == '_' || (first.is_alphabetic() && !first.is_numeric())) {
+        return None;
+    }
+    let mut cursor = at + 1 + first.len_utf8();
+    while let Some(character) = char_at(sql, cursor) {
+        if !is_identifier_continue(character) {
+            break;
+        }
+        cursor = space_end(sql, cursor + character.len_utf8());
+    }
+    (sql.as_bytes().get(cursor) == Some(&b'(')).then_some(cursor)
+}
+
+fn name_at(sql: &str, start: usize) -> &str {
+    let mut end = start;
+    while let Some(character) = char_at(sql, end) {
+        if !is_identifier_continue(character) {
+            break;
+        }
+        end += character.len_utf8();
+    }
+    &sql[start..end]
+}
+
+fn is_identifier_continue(character: char) -> bool {
+    character == '_' || character.is_alphanumeric()
+}
+
+fn space_end(sql: &str, start: usize) -> usize {
+    let mut index = start;
+    while let Some(character) = char_at(sql, index) {
+        if !is_python_space(character) {
+            break;
+        }
+        index += character.len_utf8();
+    }
+    index
+}
+
+fn char_at(sql: &str, index: usize) -> Option<char> {
+    sql.get(index..).and_then(|rest| rest.chars().next())
+}