Support parsing table valued functions

sqlparser/lib/src/analysis/types/resolver.dart

@@ -112,7 +112,7 @@ class TypeResolver {
         } else {
           return const ResolveResult.unknown();
         }
-      } else if (expr is SqlInvocation) {
+      } else if (expr is ExpressionInvocation) {
         return resolveFunctionCall(expr);
       } else if (expr is IsExpression ||
           expr is IsNullExpression ||
@@ -167,8 +167,8 @@ class TypeResolver {
     }, l);
   }
 
-  ResolveResult resolveFunctionCall(SqlInvocation call) {
-    return _cache((SqlInvocation call) {
+  ResolveResult resolveFunctionCall(ExpressionInvocation call) {
+    return _cache((ExpressionInvocation call) {
       final parameters = call.expandParameters();
       final firstNullable =
           // ignore: avoid_bool_literals_in_conditional_expressions
@@ -413,7 +413,7 @@ class TypeResolver {
         parent is Tuple ||
         parent is UnaryExpression) {
       return const ResolveResult.needsContext();
-    } else if (parent is SqlInvocation) {
+    } else if (parent is ExpressionInvocation) {
       // if we have a special case for the mix of function and argument, use
       // that. Otherwise, just assume that the argument has the same type as the
       // return type of the function

sqlparser/lib/src/analysis/types2/resolving_visitor.dart

@@ -397,7 +397,7 @@ class TypeResolver extends RecursiveVisitor<TypeExpectation, void> {
   }
 
   @override
-  void visitInvocation(SqlInvocation e, TypeExpectation arg) {
+  void visitExpressionInvocation(ExpressionInvocation e, TypeExpectation arg) {
     final type = _resolveInvocation(e);
     if (type != null) {
       session._checkAndResolve(e, type, arg);
@@ -411,7 +411,7 @@ class TypeResolver extends RecursiveVisitor<TypeExpectation, void> {
     }
   }
 
-  ResolvedType _resolveInvocation(SqlInvocation e) {
+  ResolvedType _resolveInvocation(ExpressionInvocation e) {
     final params = e.expandParameters();
     void nullableIfChildIs() {
       session._addRelation(NullableIfSomeOtherIs(e, params));

sqlparser/lib/src/ast/common/queryables.dart

@@ -8,10 +8,12 @@ abstract class Queryable extends AstNode {
     return visitor.visitQueryable(this, arg);
   }
 
+  // todo remove this, introduce more visit methods for subclasses
   T when<T>({
     @required T Function(TableReference) isTable,
     @required T Function(SelectStatementAsSource) isSelect,
     @required T Function(JoinClause) isJoin,
+    @required T Function(TableValuedFunction) isTableFunction,
   }) {
     if (this is TableReference) {
       return isTable(this as TableReference);
@@ -19,6 +21,8 @@ abstract class Queryable extends AstNode {
       return isSelect(this as SelectStatementAsSource);
     } else if (this is JoinClause) {
       return isJoin(this as JoinClause);
+    } else if (this is TableValuedFunction) {
+      return isTableFunction(this as TableValuedFunction);
     }
 
     throw StateError('Unknown subclass');
@@ -165,3 +169,25 @@ class UsingConstraint extends JoinConstraint {
 
   UsingConstraint({@required this.columnNames});
 }
+
+class TableValuedFunction extends Queryable
+    implements TableOrSubquery, SqlInvocation, Renamable {
+  @override
+  final String name;
+
+  @override
+  final String as;
+
+  @override
+  final FunctionParameters parameters;
+
+  TableValuedFunction(this.name, this.parameters, {this.as});
+
+  @override
+  Iterable<AstNode> get childNodes => [parameters];
+
+  @override
+  bool contentEquals(TableValuedFunction other) {
+    return other.name == name;
+  }
+}

sqlparser/lib/src/ast/expressions/aggregate.dart

@@ -1,7 +1,7 @@
 part of '../ast.dart';
 
 class AggregateExpression extends Expression
-    implements SqlInvocation, ReferenceOwner {
+    implements ExpressionInvocation, ReferenceOwner {
   final IdentifierToken function;
 
   @override

sqlparser/lib/src/ast/expressions/function.dart

@@ -2,16 +2,19 @@ part of '../ast.dart';
 
 /// Interface for function calls, either a [FunctionExpression] or a
 /// [AggregateExpression].
-abstract class SqlInvocation extends Expression {
+abstract class SqlInvocation implements AstNode {
   /// The name of the function being called
   String get name;
 
   FunctionParameters get parameters;
 }
 
+/// Interface for [SqlInvocation]s that are also expressions.
+abstract class ExpressionInvocation implements SqlInvocation, Expression {}
+
 class FunctionExpression extends Expression
     with ReferenceOwner
-    implements SqlInvocation {
+    implements ExpressionInvocation {
   @override
   final String name;
   @override
@@ -75,6 +78,6 @@ class ExprFunctionParameters extends FunctionParameters {
 
   @override
   bool contentEquals(ExprFunctionParameters other) {
-    return other.distinct == distinct && other.parameters == parameters;
+    return other.distinct == distinct;
   }
 }

sqlparser/lib/src/ast/visitor.dart

@@ -332,7 +332,7 @@ class RecursiveVisitor<A, R> implements AstVisitor<A, R> {
 
   @override
   R visitFunction(FunctionExpression e, A arg) {
-    return visitInvocation(e, arg);
+    return visitExpressionInvocation(e, arg);
   }
 
   R visitFunctionParameters(FunctionParameters e, A arg) {
@@ -351,7 +351,7 @@ class RecursiveVisitor<A, R> implements AstVisitor<A, R> {
 
   @override
   R visitAggregateExpression(AggregateExpression e, A arg) {
-    return visitInvocation(e, arg);
+    return visitExpressionInvocation(e, arg);
   }
 
   @override
@@ -403,8 +403,12 @@ class RecursiveVisitor<A, R> implements AstVisitor<A, R> {
     return visitExpression(e, arg);
   }
 
+  R visitExpressionInvocation(ExpressionInvocation e, A arg) {
+    return visitInvocation(e, arg);
+  }
+
   R visitInvocation(SqlInvocation e, A arg) {
-    return visitExpression(e, arg);
+    return visitChildren(e, arg);
   }
 
   R visitExpression(Expression e, A arg) {

sqlparser/lib/src/reader/parser/crud.dart

@@ -258,9 +258,22 @@ mixin CrudParser on ParserBase {
 
   TableOrSubquery _tableOrSubquery() {
     // this is what we're parsing: https://www.sqlite.org/syntax/table-or-subquery.html
-    // we currently only support regular tables and nested selects
+    // we currently only support regular tables, table functions and nested
+    // selects
     final tableRef = _tableReference();
     if (tableRef != null) {
+      // this is a bit hacky. If the table reference only consists of one
+      // identifer and it's followed by a (, it's a table-valued function
+      if (tableRef.as == null && _matchOne(TokenType.leftParen)) {
+        final params = _functionParameters();
+        _consume(TokenType.rightParen, 'Expected closing parenthesis');
+        final alias = _as();
+
+        return TableValuedFunction(tableRef.tableName, params,
+            as: alias?.identifier)
+          ..setSpan(tableRef.first, _previous);
+      }
+
       return tableRef;
     } else if (_matchOne(TokenType.leftParen)) {
       final first = _previous;

sqlparser/lib/src/reader/parser/expressions.dart

@@ -354,6 +354,7 @@ mixin ExpressionParser on ParserBase {
     return null;
   }
 
+  @override
   FunctionParameters _functionParameters() {
     if (_matchOne(TokenType.star)) {
       return StarFunctionParameter()

sqlparser/lib/src/reader/parser/parser.dart

@@ -201,6 +201,9 @@ abstract class ParserBase {
   /// Parses a block, which consists of statements between `BEGIN` and `END`.
   Block _consumeBlock();
 
+  /// Parses function parameters, without the surrounding parentheses.
+  FunctionParameters _functionParameters();
+
   /// Skips all tokens until it finds one with [type]. If [skipTarget] is true,
   /// that token will be skipped as well.
   ///

sqlparser/test/parser/select/from_test.dart

@@ -86,5 +86,37 @@ void main() {
         ),
       ]);
     });
+
+    test('table valued function', () {
+      testStatement(
+        '''
+SELECT DISTINCT user.name
+  FROM user, json_each(user.phone)
+WHERE json_each.value LIKE '704-%';
+        ''',
+        SelectStatement(
+          distinct: true,
+          columns: [
+            ExpressionResultColumn(
+              expression: Reference(tableName: 'user', columnName: 'name'),
+            ),
+          ],
+          from: [
+            TableReference('user'),
+            TableValuedFunction(
+              'json_each',
+              ExprFunctionParameters(parameters: [
+                Reference(tableName: 'user', columnName: 'phone')
+              ]),
+            ),
+          ],
+          where: StringComparisonExpression(
+            left: Reference(tableName: 'json_each', columnName: 'value'),
+            operator: token(TokenType.like),
+            right: StringLiteral(stringLiteral('704-%')),
+          ),
+        ),
+      );
+    });
   });
 }

sqlparser/test/parser/utils.dart

@@ -10,6 +10,10 @@ Token token(TokenType type) {
   return Token(type, null);
 }
 
+StringLiteralToken stringLiteral(String value) {
+  return StringLiteralToken(value, null);
+}
+
 InlineDartToken inlineDart(String dartCode) {
   return InlineDartToken(fakeSpan('`$dartCode`'));
 }