fix(mysql): execute adjacent statement on delimiter directive lines

apps/desktop/src/lib/__tests__/sql/sqlStatementRanges.spec.ts

@@ -1409,10 +1409,23 @@ FROM orders;`;
     expect(range?.sql).toBe("SELECT 1");
   });
 
-  it("skips MySQL delimiter commands when resolving the cursor statement", () => {
+  it("resolves MySQL delimiter command lines to the nearest executable statement", () => {
     const sql = "select COUNT(1) FROM your_table;\ndelimiter ;;\nselect COUNT(1) FROM your_table;\n\n;;\ndelimiter ;";
     expect(statementRangeAtCursor(sql, indexOf(sql, "COUNT", 2), "mysql")?.sql.trim()).toBe("select COUNT(1) FROM your_table;");
-    expect(statementRangeAtCursor(sql, indexOf(sql, "delimiter"), "mysql")).toBeNull();
+    // A caret on a leading `delimiter ;;` line targets the statement it introduces.
+    expect(statementRangeAtCursor(sql, indexOf(sql, "delimiter"), "mysql")?.sql.trim()).toBe("select COUNT(1) FROM your_table;");
+    // A trailing `delimiter ;` has nothing after it, so it targets the statement above.
+    expect(statementRangeAtCursor(sql, indexOf(sql, "delimiter", 2), "mysql")?.sql.trim()).toBe("select COUNT(1) FROM your_table;");
+  });
+
+  it("targets the surrounding MySQL statements for delimiter lines in a routine script", () => {
+    const routine = mysqlDelimitedRoutineFixture.slice(mysqlDelimitedRoutineFixture.indexOf("CREATE PROCEDURE"), mysqlDelimitedRoutineFixture.indexOf(" //\nDELIMITER"));
+    expect(statementRangeAtCursor(mysqlDelimitedRoutineFixture, indexOf(mysqlDelimitedRoutineFixture, "DELIMITER"), "mysql")?.sql.trim()).toBe(routine);
+    expect(statementRangeAtCursor(mysqlDelimitedRoutineFixture, indexOf(mysqlDelimitedRoutineFixture, "DELIMITER", 2), "mysql")?.sql.trim()).toBe("CALL sp_insert_random_users(100)");
+  });
+
+  it("returns null for a MySQL script made only of delimiter commands", () => {
+    expect(statementRangeAtCursor("delimiter //\n", 0, "mysql")).toBeNull();
   });
 
   it("returns the full MySQL routine block for cursors inside nested statements", () => {
@@ -1855,6 +1868,13 @@ WHERE t2.product_name = '12345'
     expect(candidateSummaries(candidates)).toEqual(["cursor:select COUNT(1) FROM your_table;", "all:select COUNT(1) FROM your_table;\ndelimiter ;;\nselect COUNT(1) FROM your_table;\n\n;;\ndelimiter ;"]);
   });
 
+  it("builds a cursor candidate for a MySQL delimiter command line (issue #9485)", () => {
+    const sql = "select COUNT(1) FROM your_table;\ndelimiter ;;\nselect COUNT(1) FROM your_table;\n\n;;\ndelimiter ;";
+    const candidates = buildExecutionCandidates(sql, indexOf(sql, "delimiter"), "mysql");
+    expect(candidateKinds(candidates)).toEqual(["cursor", "all"]);
+    expect(candidates[0].sql).toBe("select COUNT(1) FROM your_table;");
+  });
+
   it("uses the current SQL Server batch for cursor candidates", () => {
     const sql = "SELECT 1\nGO\nSELECT 2;";
     const candidates = buildExecutionCandidates(sql, indexOf(sql, "2"), "sqlserver");

apps/desktop/src/lib/sql/sqlStatementRanges.ts

@@ -709,6 +709,14 @@ export function statementRangeAtCursor(sql: string, cursorPos: number, databaseT
     }
   }
 
+  // A MySQL `delimiter X` line is a client directive, not executable SQL, so it
+  // never forms a statement range of its own. When the caret rests on such a
+  // line, target the statement the directive introduces (or the closest
+  // preceding statement when the directive ends the script) instead of
+  // reporting that there is nothing to run. See issue #9485.
+  const directiveRange = mysqlDelimiterDirectiveCursorRange(sql, pos, databaseType, parameterOptions, statements);
+  if (directiveRange) return directiveRange;
+
   return null;
 }
 
@@ -2192,6 +2200,29 @@ function parseDelimiterCommand(line: string): string | null {
   return delimiter ? delimiter : null;
 }
 
+/**
+ * Resolves a caret resting on a MySQL `delimiter X` client-directive line to
+ * the nearest executable statement: the statement the directive introduces, or
+ * the statement just before it when the directive has nothing after it.
+ */
+function mysqlDelimiterDirectiveCursorRange(sql: string, pos: number, databaseType: DatabaseType | undefined, parameterOptions: SqlParameterOptions | undefined, statements: RawStatement[]): SqlTextRange | null {
+  if (databaseType !== "mysql" || statements.length === 0) return null;
+  const lineStart = sql.lastIndexOf("\n", pos - 1) + 1;
+  const lineEnd = findLineEnd(sql, pos);
+  let directiveStart = lineStart;
+  while (directiveStart < lineEnd && (sql[directiveStart] === " " || sql[directiveStart] === "\t")) directiveStart += 1;
+  if (!startsDelimiterCommand(sql, directiveStart)) return null;
+  if (parseDelimiterCommand(sql.slice(directiveStart, lineEnd)) === null) return null;
+
+  const following = statements.find((statement) => statement.from >= lineEnd);
+  if (following) {
+    return rangeFor(splitStatementRangeAtSoftStarts(sql, following, databaseType, parameterOptions)[0] ?? following, sql);
+  }
+  const preceding = statements[statements.length - 1];
+  const precedingSoftRanges = splitStatementRangeAtSoftStarts(sql, preceding, databaseType, parameterOptions);
+  return rangeFor(precedingSoftRanges[precedingSoftRanges.length - 1] ?? preceding, sql);
+}
+
 function findLineEnd(sql: string, pos: number): number {
   const newline = sql.indexOf("\n", pos);
   const carriageReturn = sql.indexOf("\r", pos);