T-SQL support default params and no RETURN value (#2434)

* T-SQL ddetails params and no RETURN value

* Review feedback

Co-authored-by: Barry Hart <barrywhart@yahoo.com>

src/sqlfluff/dialects/dialect_tsql.py

@@ -188,6 +188,11 @@
     ParameterNameSegment=RegexParser(
         r"[@][A-Za-z0-9_]+", CodeSegment, name="parameter", type="parameter"
     ),
+    FunctionParameterGrammar=Sequence(
+        Ref("ParameterNameSegment", optional=True),
+        Ref("DatatypeSegment"),
+        Sequence(Ref("EqualsSegment"), Ref("ExpressionSegment"), optional=True),
+    ),
     FunctionNameIdentifierSegment=RegexParser(
         r"[A-Z][A-Z0-9_]*|\[[A-Z][A-Z0-9_]*\]",
         CodeSegment,
@@ -1461,7 +1466,7 @@ class ReturnStatementSegment(BaseSegment):
     type = "return_segment"
     match_grammar = Sequence(
         "RETURN",
-        Ref("ExpressionSegment"),
+        Ref("ExpressionSegment", optional=True),
         Ref("DelimiterSegment", optional=True),
     )
 

test/fixtures/dialects/tsql/function_default_params.sql

@@ -0,0 +1,6 @@
+create or alter procedure name
+  @param1 nvarchar(10) = 'test',
+  @param2 int = 21
+as begin
+  return 1;
+end

test/fixtures/dialects/tsql/function_default_params.yml

@@ -0,0 +1,48 @@
+# YML test files are auto-generated from SQL files and should not be edited by
+# hand. To help enforce this, the "hash" field in the file must match a hash
+# computed by SQLFluff when running the tests. Please run
+# `python test/generate_parse_fixture_yml.py`  to generate them after adding or
+# altering SQL files.
+_hash: 2501cb05d43246a910e1715a625e9329547f0246615cce94560e3f5bf18bc535
+file:
+  batch:
+    create_procedure_statement:
+    - keyword: create
+    - binary_operator: or
+    - keyword: alter
+    - keyword: procedure
+    - object_reference:
+        identifier: name
+    - function_parameter_list:
+      - parameter: '@param1'
+      - data_type:
+          identifier: nvarchar
+          bracketed:
+            start_bracket: (
+            expression:
+              literal: '10'
+            end_bracket: )
+      - comparison_operator:
+          raw_comparison_operator: '='
+      - expression:
+          literal: "'test'"
+      - comma: ','
+      - parameter: '@param2'
+      - data_type:
+          identifier: int
+      - comparison_operator:
+          raw_comparison_operator: '='
+      - expression:
+          literal: '21'
+    - keyword: as
+    - procedure_statement:
+        statement:
+          begin_end_block:
+          - keyword: begin
+          - statement:
+              return_segment:
+                keyword: return
+                expression:
+                  literal: '1'
+                statement_terminator: ;
+          - keyword: end

test/fixtures/dialects/tsql/function_no_return.sql

@@ -0,0 +1,14 @@
+CREATE PROCEDURE findjobs @nm sysname = NULL
+AS
+IF @nm IS NULL
+    BEGIN
+        PRINT 'You must give a user name'
+        RETURN
+    END
+ELSE
+    BEGIN
+        SELECT o.name, o.id, o.uid
+        FROM sysobjects o INNER JOIN master..syslogins l
+            ON o.uid = l.sid
+        WHERE l.name = @nm
+    END;

test/fixtures/dialects/tsql/function_no_return.yml

@@ -0,0 +1,116 @@
+# YML test files are auto-generated from SQL files and should not be edited by
+# hand. To help enforce this, the "hash" field in the file must match a hash
+# computed by SQLFluff when running the tests. Please run
+# `python test/generate_parse_fixture_yml.py`  to generate them after adding or
+# altering SQL files.
+_hash: 421175885d34b10910511e8d2a7a277da2928fd4fa4ae698210aac7159928a59
+file:
+  batch:
+    create_procedure_statement:
+    - keyword: CREATE
+    - keyword: PROCEDURE
+    - object_reference:
+        identifier: findjobs
+    - function_parameter_list:
+        parameter: '@nm'
+        data_type:
+          identifier: sysname
+        comparison_operator:
+          raw_comparison_operator: '='
+        expression:
+          literal: 'NULL'
+    - keyword: AS
+    - procedure_statement:
+        statement:
+          if_then_statement:
+          - if_clause:
+              keyword: IF
+              expression:
+              - column_reference:
+                  parameter: '@nm'
+              - keyword: IS
+              - keyword: 'NULL'
+          - statement:
+              begin_end_block:
+              - keyword: BEGIN
+              - statement:
+                  print_statement:
+                    keyword: PRINT
+                    expression:
+                      literal: "'You must give a user name'"
+              - statement:
+                  return_segment:
+                    keyword: RETURN
+              - keyword: END
+          - keyword: ELSE
+          - statement:
+              begin_end_block:
+              - keyword: BEGIN
+              - statement:
+                  select_statement:
+                    select_clause:
+                    - keyword: SELECT
+                    - select_clause_element:
+                        column_reference:
+                        - identifier: o
+                        - dot: .
+                        - identifier: name
+                    - comma: ','
+                    - select_clause_element:
+                        column_reference:
+                        - identifier: o
+                        - dot: .
+                        - identifier: id
+                    - comma: ','
+                    - select_clause_element:
+                        column_reference:
+                        - identifier: o
+                        - dot: .
+                        - identifier: uid
+                    from_clause:
+                      keyword: FROM
+                      from_expression:
+                        from_expression_element:
+                          table_expression:
+                            table_reference:
+                              identifier: sysobjects
+                          alias_expression:
+                            identifier: o
+                        join_clause:
+                        - keyword: INNER
+                        - keyword: JOIN
+                        - from_expression_element:
+                            table_expression:
+                              table_reference:
+                              - identifier: master
+                              - dot: .
+                              - dot: .
+                              - identifier: syslogins
+                            alias_expression:
+                              identifier: l
+                        - join_on_condition:
+                            keyword: 'ON'
+                            expression:
+                            - column_reference:
+                              - identifier: o
+                              - dot: .
+                              - identifier: uid
+                            - comparison_operator:
+                                raw_comparison_operator: '='
+                            - column_reference:
+                              - identifier: l
+                              - dot: .
+                              - identifier: sid
+                    where_clause:
+                      keyword: WHERE
+                      expression:
+                      - column_reference:
+                        - identifier: l
+                        - dot: .
+                        - identifier: name
+                      - comparison_operator:
+                          raw_comparison_operator: '='
+                      - column_reference:
+                          parameter: '@nm'
+              - keyword: END
+          - statement_terminator: ;