Preserve MSSQL national string quotes

Author: lovasoa

src/webserver/database/sql.rs

@@ -11,7 +11,7 @@ use sqlparser::ast::helpers::attached_token::AttachedToken;
 use sqlparser::ast::{
     CastKind, DataType, Expr, Function, FunctionArg, FunctionArgExpr, FunctionArgumentList,
     FunctionArguments, Ident, ObjectName, ObjectNamePart, SelectFlavor, SelectItem, Set, SetExpr,
-    Spanned, Statement, Value, ValueWithSpan,
+    Spanned, Statement, Value, ValueWithSpan, VisitMut, VisitorMut,
 };
 use sqlparser::dialect::{
     Dialect, DuckDbDialect, GenericDialect, MsSqlDialect, MySqlDialect, OracleDialect,
@@ -22,6 +22,7 @@ use sqlparser::tokenizer::Token::{self, EOF, SemiColon};
 use sqlparser::tokenizer::{Location, Span, TokenWithSpan, Tokenizer};
 use sqlx::any::AnyKind;
 use std::fmt::Write;
+use std::ops::ControlFlow;
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
 
@@ -234,6 +235,7 @@ fn parse_single_statement(
         return Some(ParsedStatement::Error(err));
     }
     let json_columns = extract_json_columns(&stmt, dbms);
+    escape_national_string_literals_for_display(&mut stmt);
     let query = format!(
         "{stmt}{semicolon}",
         semicolon = if semicolon { ";" } else { "" }
@@ -250,6 +252,24 @@ fn parse_single_statement(
     Some(ParsedStatement::StmtWithParams(stmt_with_params))
 }
 
+fn escape_national_string_literals_for_display(stmt: &mut Statement) {
+    struct NationalStringEscaper;
+
+    impl VisitorMut for NationalStringEscaper {
+        type Break = std::convert::Infallible;
+
+        fn pre_visit_value(&mut self, value: &mut ValueWithSpan) -> ControlFlow<Self::Break> {
+            if let Value::NationalStringLiteral(s) = &mut value.value {
+                // sqlparser 0.62 does not escape NationalStringLiteral when formatting the AST.
+                *s = s.replace('\'', "''");
+            }
+            ControlFlow::Continue(())
+        }
+    }
+
+    let _ = stmt.visit(&mut NationalStringEscaper);
+}
+
 fn extract_query_start(stmt: &impl Spanned) -> SourceSpan {
     let location = stmt.span();
     SourceSpan {
@@ -1020,6 +1040,19 @@ mod test {
         assert_eq!(parameters, [StmtParam::PostOrGet("1".to_string()),]);
     }
 
+    #[test]
+    fn test_mssql_national_string_literal_rewrite() {
+        let sql = r#"select N'Tu geres '';'' et ''"'' ?' as msg"#;
+        let db_info = create_test_db_info(SupportedDatabase::Mssql);
+        let mut parsed = parse_sql(&db_info, &MsSqlDialect {}, sql).unwrap();
+        match parsed.next().expect("expected one statement") {
+            ParsedStatement::StmtWithParams(stmt) => {
+                assert_eq!(stmt.query, r#"SELECT N'Tu geres '';'' et ''"'' ?' AS msg"#);
+            }
+            other => panic!("expected a database statement: {other:?}"),
+        }
+    }
+
     #[test]
     fn test_static_extract() {
         use SimpleSelectValue::Static;

tests/data_formats/csv_data_mssql.sql

@@ -8,4 +8,4 @@ select
 union all
 select
     1 as id,
-    CONCAT(N'Tu gères ', NCHAR(39), NCHAR(59), NCHAR(39), N' et ', NCHAR(39), NCHAR(34), NCHAR(39), N' ?') as msg;
+    N'Tu gères '';'' et ''"'' ?' as msg;