Prevent exceptions when running fix on dialect fixtures

src/sqlfluff/core/rules/analysis/select.py

@@ -80,7 +80,7 @@ def get_select_statement_info(
     for ref in reference_buffer.copy():
         ref_path = segment.path_to(ref)
         # is it in a subselect? i.e. a select which isn't this one.
-        if any(
+        if ref_path and any(
             seg.is_type("select_statement") and seg is not segment for seg in ref_path
         ):
             reference_buffer.remove(ref)

src/sqlfluff/core/rules/base.py

@@ -802,28 +802,32 @@ def _choose_anchor_segment(
 
         anchor: BaseSegment = segment
         child: BaseSegment = segment
-        for seg in context.parent_stack[0].path_to(segment)[1:-1][::-1]:
-            # Which lists of children to check against.
-            children_lists: List[List[BaseSegment]] = []
-            if filter_meta:
-                # Optionally check against filtered (non-meta only) children.
-                children_lists.append(
-                    [child for child in seg.segments if not child.is_meta]
-                )
-            # Always check against the full set of children.
-            children_lists.append(seg.segments)
-            children: List[BaseSegment]
-            for children in children_lists:
-                if edit_type == "create_before" and children[0] is child:
-                    anchor = seg
-                    assert anchor.raw.startswith(segment.raw)
-                    child = seg
-                    break
-                elif edit_type == "create_after" and children[-1] is child:
-                    anchor = seg
-                    assert anchor.raw.endswith(segment.raw)
-                    child = seg
-                    break
+        parent: BaseSegment = context.parent_stack[0]
+        path: Optional[List[BaseSegment]] = parent.path_to(segment) if parent else None
+        inner_path: Optional[List[BaseSegment]] = path[1:-1] if path else None
+        if inner_path:
+            for seg in inner_path[::-1]:
+                # Which lists of children to check against.
+                children_lists: List[List[BaseSegment]] = []
+                if filter_meta:
+                    # Optionally check against filtered (non-meta only) children.
+                    children_lists.append(
+                        [child for child in seg.segments if not child.is_meta]
+                    )
+                # Always check against the full set of children.
+                children_lists.append(seg.segments)
+                children: List[BaseSegment]
+                for children in children_lists:
+                    if edit_type == "create_before" and children[0] is child:
+                        anchor = seg
+                        assert anchor.raw.startswith(segment.raw)
+                        child = seg
+                        break
+                    elif edit_type == "create_after" and children[-1] is child:
+                        anchor = seg
+                        assert anchor.raw.endswith(segment.raw)
+                        child = seg
+                        break
         return anchor
 
     @staticmethod

src/sqlfluff/rules/L026.py

@@ -148,7 +148,10 @@ def _should_ignore_reference(reference, selectable):
         # - They are the target table, similar to an INSERT or UPDATE
         #   statement, thus not expected to match a table in the FROM
         #   clause.
-        return any(seg.is_type("into_table_clause") for seg in ref_path)
+        if ref_path:
+            return any(seg.is_type("into_table_clause") for seg in ref_path)
+        else:
+            return False  # pragma: no cover
 
     @staticmethod
     def _get_table_refs(ref, dialect):

src/sqlfluff/rules/L028.py

@@ -128,8 +128,7 @@ def _generate_fixes(
 ) -> Optional[List[LintResult]]:
     """Iterate through references and check consistency."""
     # How many aliases are there? If more than one then abort.
-    assert len(table_aliases) > 0, "Only Selects with tables should be checked"
-    if len(table_aliases) > 1:
+    if len(table_aliases) != 1:
         return None
 
     # A buffer to keep any violations.

test/fixtures/rules/std_rule_cases/L020.yml

@@ -33,3 +33,13 @@ test_pass_subquery:
         from table_1 as a
         join table_2 as b on a.pk = b.pk
     ) AS a
+
+test_pass_bigquery_function:
+  pass_str: |
+    SELECT
+        gcpproject.functions.timestamp_parsing(log_tbl.orderdate) AS orderdate
+    FROM
+        `gcp-project.data.year_2021` AS log_tbl
+  configs:
+    core:
+      dialect: bigquery

test/fixtures/rules/std_rule_cases/L026.yml

@@ -200,3 +200,10 @@ test_tsql_select_system_as_identifier:
   configs:
     core:
       dialect: tsql
+
+test_mysql_select_no_from_should_not_except:
+  pass_str: |
+    SELECT DATE_SUB('1992-12-31 23:59:59.000002', INTERVAL '1.999999' SECOND_MICROSECOND);
+  configs:
+    core:
+      dialect: mysql

test/fixtures/rules/std_rule_cases/L028.yml

@@ -282,3 +282,21 @@ test_pass_tsql_parameter:
   configs:
     core:
       dialect: tsql
+
+test_pass_tsql_pivot:
+  # This should pass for certain dialects
+  pass_str: |
+    SELECT 1
+    FROM
+    (
+      SELECT DaysToManufacture, StandardCost
+      FROM Production.Product
+    ) AS SourceTable
+    PIVOT
+    (
+      AVG(StandardCost)
+      FOR DaysToManufacture IN ([0], [1], [2], [3], [4])
+    ) AS PivotTable;
+  configs:
+    core:
+      dialect: tsql

test/test_rules_against_dialect_fixtures.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+
+echo "This script will run 'sqlfluff fix -f' on all our dialect fixtures"
+echo "to look for critical errors."
+echo "WARNING this will change the fixtures so do not commit these changes!"
+
+DIALECTS=($( ls -d test/fixtures/dialects/*/ ))
+for DIALECT in "${DIALECTS[@]}"
+do
+    echo "Testing $DIALECT SQL files fix without critical errors..."
+    OUTPUT=$(sqlfluff fix -f ${DIALECT})
+    echo "${OUTPUT}" | grep -i -q critical
+    # exit error, if match
+    if  [ $? -eq 0 ]; then
+        echo "Critical errors found:"
+        echo "${OUTPUT}" | grep -i "critical\|test/fixtures" | grep -i critical -A 1
+        exit 1
+    fi
+done
+
+echo "WARNING If running locally you should revert the changes."

tox.ini

@@ -84,7 +84,7 @@ commands = doc8 {toxinidir}/docs/source --file-encoding utf8
 
 [testenv:ruleslinting]
 allowlist_externals = sh
-commands = {toxinidir}/test/test-lint-rules.sh
+commands = {toxinidir}/test/test_rules_against_dialect_fixtures.sh
 
 
 [testenv:docbuild]