Introduce an isNull() method in the ExpressionGenerator class

mrigger · mrigger · commit 44b292ae881c · 2020-07-14T23:45:22.000+02:00
diff --git a/src/sqlancer/clickhouse/gen/ClickHouseExpressionGenerator.java b/src/sqlancer/clickhouse/gen/ClickHouseExpressionGenerator.java
@@ -18,6 +18,7 @@
 import sqlancer.clickhouse.ast.ClickHouseExpression;
 import sqlancer.clickhouse.ast.ClickHouseUnaryPostfixOperation;
 import sqlancer.clickhouse.ast.ClickHouseUnaryPrefixOperation;
+import sqlancer.clickhouse.ast.ClickHouseUnaryPostfixOperation.ClickHouseUnaryPostfixOperator;
 import sqlancer.clickhouse.ast.ClickHouseUnaryPrefixOperation.ClickHouseUnaryPrefixOperator;
 import sqlancer.gen.TypedExpressionGenerator;
 
@@ -175,4 +176,9 @@ public ClickHouseExpression generatePredicate() {
     public ClickHouseExpression negatePredicate(ClickHouseExpression predicate) {
         return new ClickHouseUnaryPrefixOperation(predicate, ClickHouseUnaryPrefixOperator.NOT);
     }
+
+    @Override
+    public ClickHouseExpression isNull(ClickHouseExpression expr) {
+        return new ClickHouseUnaryPostfixOperation(expr, ClickHouseUnaryPostfixOperator.IS_NULL, false);
+    }
 }
diff --git a/src/sqlancer/cockroachdb/gen/CockroachDBExpressionGenerator.java b/src/sqlancer/cockroachdb/gen/CockroachDBExpressionGenerator.java
@@ -353,4 +353,9 @@ public CockroachDBExpression negatePredicate(CockroachDBExpression predicate) {
         return new CockroachDBNotOperation(predicate);
     }
 
+    @Override
+    public CockroachDBExpression isNull(CockroachDBExpression expr) {
+        return new CockroachDBUnaryPostfixOperation(expr, CockroachDBUnaryPostfixOperator.IS_NULL);
+    }
+
 }
diff --git a/src/sqlancer/duckdb/gen/DuckDBExpressionGenerator.java b/src/sqlancer/duckdb/gen/DuckDBExpressionGenerator.java
@@ -438,4 +438,9 @@ public Node<DuckDBExpression> negatePredicate(Node<DuckDBExpression> predicate)
         return new NewUnaryPrefixOperatorNode<>(predicate, DuckDBUnaryPrefixOperator.NOT);
     }
 
+    @Override
+    public Node<DuckDBExpression> isNull(Node<DuckDBExpression> expr) {
+        return new NewUnaryPostfixOperatorNode<>(expr, DuckDBUnaryPostfixOperator.IS_NULL);
+    }
+
 }
diff --git a/src/sqlancer/gen/ExpressionGenerator.java b/src/sqlancer/gen/ExpressionGenerator.java
@@ -19,4 +19,14 @@ public interface ExpressionGenerator<E> {
      */
     E negatePredicate(E predicate);
 
+    /**
+     * Checks if an expression evaluates to NULL (i.e., implements the IS NULL operator).
+     *
+     * @param expr
+     *            the expression
+     *
+     * @return an expression that checks whether the expression evaluates to NULL.
+     */
+    E isNull(E expr);
+
 }
diff --git a/src/sqlancer/mysql/gen/MySQLExpressionGenerator.java b/src/sqlancer/mysql/gen/MySQLExpressionGenerator.java
@@ -193,4 +193,9 @@ public MySQLExpression negatePredicate(MySQLExpression predicate) {
         return new MySQLUnaryPrefixOperation(predicate, MySQLUnaryPrefixOperator.NOT);
     }
 
+    @Override
+    public MySQLExpression isNull(MySQLExpression expr) {
+        return new MySQLUnaryPostfixOperation(expr, MySQLUnaryPostfixOperation.UnaryPostfixOperator.IS_NULL, false);
+    }
+
 }
diff --git a/src/sqlancer/postgres/gen/PostgresExpressionGenerator.java b/src/sqlancer/postgres/gen/PostgresExpressionGenerator.java
@@ -585,4 +585,9 @@ public PostgresExpression negatePredicate(PostgresExpression predicate) {
         return new PostgresPrefixOperation(predicate, PostgresPrefixOperation.PrefixOperator.NOT);
     }
 
+    @Override
+    public PostgresExpression isNull(PostgresExpression expr) {
+        return new PostgresPostfixOperation(expr, PostfixOperator.IS_NULL);
+    }
+
 }
diff --git a/src/sqlancer/sqlite3/gen/SQLite3ExpressionGenerator.java b/src/sqlancer/sqlite3/gen/SQLite3ExpressionGenerator.java
@@ -29,6 +29,7 @@
 import sqlancer.sqlite3.ast.SQLite3Expression.SQLite3OrderingTerm;
 import sqlancer.sqlite3.ast.SQLite3Expression.SQLite3OrderingTerm.Ordering;
 import sqlancer.sqlite3.ast.SQLite3Expression.SQLite3PostfixText;
+import sqlancer.sqlite3.ast.SQLite3Expression.SQLite3PostfixUnaryOperation;
 import sqlancer.sqlite3.ast.SQLite3Expression.SQLite3PostfixUnaryOperation.PostfixUnaryOperator;
 import sqlancer.sqlite3.ast.SQLite3Expression.Sqlite3BinaryOperation;
 import sqlancer.sqlite3.ast.SQLite3Expression.Sqlite3BinaryOperation.BinaryOperator;
@@ -651,4 +652,9 @@ public SQLite3Expression negatePredicate(SQLite3Expression predicate) {
         return new SQLite3UnaryOperation(UnaryOperator.NOT, predicate);
     }
 
+    @Override
+    public SQLite3Expression isNull(SQLite3Expression expr) {
+        return new SQLite3PostfixUnaryOperation(PostfixUnaryOperator.ISNULL, expr);
+    }
+
 }
diff --git a/src/sqlancer/tidb/TiDBExpressionGenerator.java b/src/sqlancer/tidb/TiDBExpressionGenerator.java
@@ -175,4 +175,9 @@ public TiDBExpression negatePredicate(TiDBExpression predicate) {
         return new TiDBUnaryPrefixOperation(predicate, TiDBUnaryPrefixOperator.NOT);
     }
 
+    @Override
+    public TiDBExpression isNull(TiDBExpression expr) {
+        return new TiDBUnaryPostfixOperation(expr, TiDBUnaryPostfixOperator.IS_NULL);
+    }
+
 }

Original file line number	Diff line number	Diff line change
`@@ -353,4 +353,9 @@ public CockroachDBExpression negatePredicate(CockroachDBExpression predicate) {`
`353`	`353`	`return new CockroachDBNotOperation(predicate);`
`354`	`354`	`}`
`355`	`355`
	`356`	`+ @Override`
	`357`	`+ public CockroachDBExpression isNull(CockroachDBExpression expr) {`
	`358`	`+ return new CockroachDBUnaryPostfixOperation(expr, CockroachDBUnaryPostfixOperator.IS_NULL);`
	`359`	`+ }`
	`360`	`+`
`356`	`361`	`}`
Original file line number	Diff line number	Diff line change
`@@ -438,4 +438,9 @@ public Node<DuckDBExpression> negatePredicate(Node<DuckDBExpression> predicate)`
`438`	`438`	`return new NewUnaryPrefixOperatorNode<>(predicate, DuckDBUnaryPrefixOperator.NOT);`
`439`	`439`	`}`
`440`	`440`
	`441`	`+ @Override`
	`442`	`+ public Node<DuckDBExpression> isNull(Node<DuckDBExpression> expr) {`
	`443`	`+ return new NewUnaryPostfixOperatorNode<>(expr, DuckDBUnaryPostfixOperator.IS_NULL);`
	`444`	`+ }`
	`445`	`+`
`441`	`446`	`}`
Original file line number	Diff line number	Diff line change
`@@ -193,4 +193,9 @@ public MySQLExpression negatePredicate(MySQLExpression predicate) {`
`193`	`193`	`return new MySQLUnaryPrefixOperation(predicate, MySQLUnaryPrefixOperator.NOT);`
`194`	`194`	`}`
`195`	`195`
	`196`	`+ @Override`
	`197`	`+ public MySQLExpression isNull(MySQLExpression expr) {`
	`198`	`+ return new MySQLUnaryPostfixOperation(expr, MySQLUnaryPostfixOperation.UnaryPostfixOperator.IS_NULL, false);`
	`199`	`+ }`
	`200`	`+`
`196`	`201`	`}`
Original file line number	Diff line number	Diff line change
`@@ -585,4 +585,9 @@ public PostgresExpression negatePredicate(PostgresExpression predicate) {`
`585`	`585`	`return new PostgresPrefixOperation(predicate, PostgresPrefixOperation.PrefixOperator.NOT);`
`586`	`586`	`}`
`587`	`587`
	`588`	`+ @Override`
	`589`	`+ public PostgresExpression isNull(PostgresExpression expr) {`
	`590`	`+ return new PostgresPostfixOperation(expr, PostfixOperator.IS_NULL);`
	`591`	`+ }`
	`592`	`+`
`588`	`593`	`}`
Original file line number	Diff line number	Diff line change
`@@ -175,4 +175,9 @@ public TiDBExpression negatePredicate(TiDBExpression predicate) {`
`175`	`175`	`return new TiDBUnaryPrefixOperation(predicate, TiDBUnaryPrefixOperator.NOT);`
`176`	`176`	`}`
`177`	`177`
	`178`	`+ @Override`
	`179`	`+ public TiDBExpression isNull(TiDBExpression expr) {`
	`180`	`+ return new TiDBUnaryPostfixOperation(expr, TiDBUnaryPostfixOperator.IS_NULL);`
	`181`	`+ }`
	`182`	`+`
`178`	`183`	`}`