Extend SHOW FUNCTIONS to display whether functions have variable arity

presto-main/src/main/java/com/facebook/presto/sql/rewrite/ShowQueriesRewrite.java

@@ -28,6 +28,7 @@
 import com.facebook.presto.spi.StandardErrorCode;
 import com.facebook.presto.spi.TableHandle;
 import com.facebook.presto.spi.function.FunctionKind;
+import com.facebook.presto.spi.function.Signature;
 import com.facebook.presto.spi.function.SqlFunction;
 import com.facebook.presto.spi.security.PrestoPrincipal;
 import com.facebook.presto.spi.security.PrincipalType;
@@ -525,15 +526,17 @@ protected Node visitShowFunctions(ShowFunctions node, Void context)
         {
             ImmutableList.Builder<Expression> rows = ImmutableList.builder();
             for (SqlFunction function : metadata.listFunctions(session)) {
+                Signature signature = function.getSignature();
                 rows.add(row(
-                        function.getSignature().getName().getFunctionNamespace().equals(DEFAULT_NAMESPACE) ?
-                                new StringLiteral(function.getSignature().getNameSuffix()) :
-                                new StringLiteral(function.getSignature().getName().toString()),
-                        new StringLiteral(function.getSignature().getReturnType().toString()),
-                        new StringLiteral(Joiner.on(", ").join(function.getSignature().getArgumentTypes())),
+                        signature.getName().getFunctionNamespace().equals(DEFAULT_NAMESPACE) ?
+                                new StringLiteral(signature.getNameSuffix()) :
+                                new StringLiteral(signature.getName().toString()),
+                        new StringLiteral(signature.getReturnType().toString()),
+                        new StringLiteral(Joiner.on(", ").join(signature.getArgumentTypes())),
                         new StringLiteral(getFunctionType(function)),
                         function.isDeterministic() ? TRUE_LITERAL : FALSE_LITERAL,
-                        new StringLiteral(nullToEmpty(function.getDescription()))));
+                        new StringLiteral(nullToEmpty(function.getDescription())),
+                        signature.isVariableArity() ? TRUE_LITERAL : FALSE_LITERAL));
             }
 
             Map<String, String> columns = ImmutableMap.<String, String>builder()
@@ -543,6 +546,7 @@ protected Node visitShowFunctions(ShowFunctions node, Void context)
                     .put("function_type", "Function Type")
                     .put("deterministic", "Deterministic")
                     .put("description", "Description")
+                    .put("variable_arity", "Variable Arity")
                     .build();
 
             return simpleQuery(

presto-product-tests/src/main/resources/sql-tests/testcases/array_functions/checkArrayFunctionsRegistered.result

@@ -1,10 +1,10 @@
 -- delimiter: |; ignoreOrder: true; ignoreExcessRows: true; trimValues:true
- concat | array(E) | E, array(E) | scalar | true | Concatenates an element to an array |
- concat | array(E) | array(E), E | scalar | true | Concatenates an array to an element |
- concat | array(E) | array(E) | scalar | true | Concatenates given arrays |
- cardinality | bigint | array(E) | scalar | true | Returns the cardinality (length) of the array |
- contains | boolean | array(T), T | scalar | true | Determines whether given value exists in the array |
- array_sort | array(E) | array(E) | scalar | true | Sorts the given array in ascending order according to the natural ordering of its elements. |
- array_sort | array(T) | array(T), function(T,T,integer) | scalar | true | Sorts the given array with a lambda comparator. |
- array_intersect | array(E) | array(E), array(E) | scalar | true | Intersects elements of the two given arrays |
- array_distinct | array(E) | array(E) | scalar | true | Remove duplicate values from the given array |
+ concat | array(E) | E, array(E) | scalar | true | Concatenates an element to an array | false |
+ concat | array(E) | array(E), E | scalar | true | Concatenates an array to an element | false |
+ concat | array(E) | array(E) | scalar | true | Concatenates given arrays | true |
+ cardinality | bigint | array(E) | scalar | true | Returns the cardinality (length) of the array | false |
+ contains | boolean | array(T), T | scalar | true | Determines whether given value exists in the array | false |
+ array_sort | array(E) | array(E) | scalar | true | Sorts the given array in ascending order according to the natural ordering of its elements. | false |
+ array_sort | array(T) | array(T), function(T,T,integer) | scalar | true | Sorts the given array with a lambda comparator. | false |
+ array_intersect | array(E) | array(E), array(E) | scalar | true | Intersects elements of the two given arrays | false |
+ array_distinct | array(E) | array(E) | scalar | true | Remove duplicate values from the given array | false |

presto-product-tests/src/main/resources/sql-tests/testcases/binary_functions/checkBinaryFunctionsRegistered.result

@@ -1,9 +1,9 @@
 -- delimiter: |; ignoreOrder: true; ignoreExcessRows: true; trimValues:true
- length | bigint | varbinary | scalar | true | length of the given binary |
- to_base64 | varchar | varbinary | scalar | true | encode binary data as base64 |
- to_base64url | varchar | varbinary | scalar | true | encode binary data as base64 using the URL safe alphabet |
- to_hex | varchar | varbinary | scalar | true | encode binary data as hex |
- from_base64 | varbinary | varbinary | scalar | true | decode base64 encoded binary data |
- from_base64 | varbinary | varchar(x) | scalar | true | decode base64 encoded binary data |
- from_base64url | varbinary | varbinary | scalar | true | decode URL safe base64 encoded binary data |
- from_base64url | varbinary | varchar(x) | scalar | true | decode URL safe base64 encoded binary data |
+ length | bigint | varbinary | scalar | true | length of the given binary | false |
+ to_base64 | varchar | varbinary | scalar | true | encode binary data as base64 | false |
+ to_base64url | varchar | varbinary | scalar | true | encode binary data as base64 using the URL safe alphabet | false |
+ to_hex | varchar | varbinary | scalar | true | encode binary data as hex | false |
+ from_base64 | varbinary | varbinary | scalar | true | decode base64 encoded binary data | false |
+ from_base64 | varbinary | varchar(x) | scalar | true | decode base64 encoded binary data | false |
+ from_base64url | varbinary | varbinary | scalar | true | decode URL safe base64 encoded binary data | false |
+ from_base64url | varbinary | varchar(x) | scalar | true | decode URL safe base64 encoded binary data | false |

presto-product-tests/src/main/resources/sql-tests/testcases/catalog/showFunctions.result

@@ -1,4 +1,4 @@
 -- delimiter: |; ignoreOrder: true; ignoreExcessRows:true; trimValues:true;
- abs        | bigint   | bigint     | scalar        | true          | absolute value     |
- abs        | double   | double     | scalar        | true          | absolute value     |
- acos       | double   | double     | scalar        | true          | arc cosine         |
+ abs        | bigint   | bigint     | scalar        | true          | absolute value     | false   |
+ abs        | double   | double     | scalar        | true          | absolute value     | false   |
+ acos       | double   | double     | scalar        | true          | arc cosine         | false   |