correctly treat backslash in datafusion-cli

datafusion-cli/src/helper.rs

@@ -170,28 +170,44 @@ impl Helper for CliHelper {}
 ///
 /// The data read from stdio will be escaped, so we need to unescape the input before executing the input
 pub fn unescape_input(input: &str) -> datafusion::error::Result<String> {
-    let mut chars = input.chars();
-
+    let mut chars = input.chars().peekable();
     let mut result = String::with_capacity(input.len());
-    while let Some(char) = chars.next() {
-        if char == '\\' {
-            if let Some(next_char) = chars.next() {
-                // https://static.rust-lang.org/doc/master/reference.html#literals
-                result.push(match next_char {
-                    '0' => '\0',
-                    'n' => '\n',
-                    'r' => '\r',
-                    't' => '\t',
-                    '\\' => '\\',
+
+    while let Some(ch) = chars.next() {
+        if ch == '\\' {
+            if let Some(&next) = chars.peek() {
+                match next {
+                    '0' => {
+                        chars.next();
+                        result.push('\0');
+                    }
+                    'n' => {
+                        chars.next();
+                        result.push('\n');
+                    }
+                    'r' => {
+                        chars.next();
+                        result.push('\r');
+                    }
+                    't' => {
+                        chars.next();
+                        result.push('\t');
+                    }
+                    '\\' | '\'' => result.push('\\'),
                     _ => {
-                        return Err(sql_datafusion_err!(ParserError::TokenizerError(
-                            format!("unsupported escape char: '\\{}'", next_char)
+                        return Err(DataFusionError::Execution(format!(
+                            "Invalid escape sequence: \\{}",
+                            next
                         )))
                     }
-                });
+                }
+            } else {
+                return Err(sql_datafusion_err!(ParserError::TokenizerError(
+                    "incomplete escape sequence: trailing backslash".to_string()
+                )));
             }
         } else {
-            result.push(char);
+            result.push(ch);
         }
     }
 
@@ -310,14 +326,13 @@ mod tests {
          )?;
         assert!(matches!(result, ValidationResult::Valid(None)));
 
-        // should be invalid
         let result = readline_direct(
-             Cursor::new(
-                 r"create external table test stored as csv location 'data.csv' options ('format.delimiter' '\u{07}');"
-                     .as_bytes()),
-             &validator,
-         )?;
-        assert!(matches!(result, ValidationResult::Invalid(Some(_))));
+            Cursor::new(
+                r"select '\', '\\', '\\\\\', 'dsdsds\\\\', '\t', '\0', '\n';".as_bytes(),
+            ),
+            &validator,
+        )?;
+        assert!(matches!(result, ValidationResult::Valid(None)));
 
         Ok(())
     }

datafusion-cli/tests/cli_integration.rs

@@ -39,6 +39,10 @@ fn init() {
     ["--command", "select 1; select 2;", "--format", "json", "-q"],
     "[{\"Int64(1)\":1}]\n[{\"Int64(2)\":2}]\n"
 )]
+#[case::exec_backslash(
+    ["--file", "tests/data/backslash.txt", "--format", "json", "-q"],
+    "[{\"Utf8(\\\"\\\\\\\")\":\"\\\\\",\"Utf8(\\\"\\\\\\\\\\\")\":\"\\\\\\\\\",\"Utf8(\\\"\\\\\\\\\\\\\\\\\\\\\\\")\":\"\\\\\\\\\\\\\\\\\\\\\",\"Utf8(\\\"dsdsds\\\\\\\\\\\\\\\\\\\")\":\"dsdsds\\\\\\\\\\\\\\\\\",\"Utf8(\\\"\\t\\\")\":\"\\t\",\"Utf8(\\\"\\u0000\\\")\":\"\\u0000\",\"Utf8(\\\"\\n\\\")\":\"\\n\"}]\n"
+)]
 #[case::exec_from_files(
     ["--file", "tests/data/sql.txt", "--format", "json", "-q"],
     "[{\"Int64(1)\":1}]\n"

datafusion-cli/tests/data/backslash.txt

@@ -0,0 +1 @@
+select '\', '\\', '\\\\\', 'dsdsds\\\\', '\t', '\0', '\n';